Control and power module for integrated alternator-starter

(12) PATENT DESCRIPTION (19) PL (11) 210932 (13) B1 (21) Application number: 375199 (51) Int.Cl.

(22) Filing date: 07/04/2003 H02P 9/30 (2006.01) (86) Date and number of the international application:

2003-07-04, PCT / FR03 / 002092 (87) Date and publication number of the international application:

2004-01-15, WO04 / 006423 (54)

Control and power device of the alternator-starter

<td></td><td>(73) The right holder of the patent:</td>

<td>(30) Priority:</td><td>VALEO EQUIPEMENTS ELECTRIQUES</td>

<td>2002-07-04, FR, 0208420</td><td>MOTEUR, Creteil Cedex, FR</td>

<td>2003-06-18, FR, 0307378</td><td>(72) Inventor (s):</td>

<td>(43) Application was announced:</td><td>JEAN-MARIE PIERRET, Paris, FR</td>

<td>28.11.2005 BUP 24/05</td><td>JEAN-JULIEN PFIFFER, Montgeron, FR FABRICE TAUVRON, Athis-Mons, FR</td>

<td>(45) The grant of the patent was announced:</td><td></td>

<td>30.03.2012 WUP 03/12</td><td>(74) Representative:</td>

<td></td><td>item. stalemate. Józef Wlasienko</td>

PL 210 932 B1

Description of the invention

The field of technology

The subject of the invention is a rotating and reversible electric machine, such as an alternator-starter, intended in particular, on the one hand, for supplying electricity to the on-board network of a car and for charging the car's battery and, on the other hand, for starting a car's thermal engine. The invention relates in particular to a control and power module for controlling such a machine.

State of the art

In a car, an alternator converts the rotation of the field rotor, driven by the car's heat engine, into an electric current excited in the stator windings.

The alternator may also be reversible and constitute an electric motor or a rotating electric machine allowing rotation, through the rotor shaft, of the car's thermal engine. This reversible alternator is called an alternator-starter. It converts mechanical energy into electrical energy and vice versa. Thus, the alternator-starter may start the thermal engine of the car or also act as an engine for propelling the car. In general, the stator has three windings so that the alternator is of the three-phase type. In a variation, the alternator is of the six-phase type and may be wound with conductive bars forming pins. When the alternator-starter is operated as a starter or engine, it transfers a very high torque to the heat engine.

This machine of the multiphase and reversible type therefore works as an alternator, in particular for recharging the car's battery, and as a starter for driving an internal combustion engine, also called a car's heat engine, to start it.

For this purpose, the power unit connected to the alternator armature phases serves as a control bridge for these phases in the motor running mode and acts as a rectifier bridge when the alternator-starter is operating as an alternator.

Fig. 20 represents a rotating electrical machine forming an alternator-starter in the prior art as described in WO 01/69762.

In this figure, the right part corresponds to the front of the machine and the left part corresponds to the rear of the machine. This rotating alternator forming machine includes:

the wound rotor 743 is a field box conventionally coupled to two commutator rings 706,707 and two brushes through which an excitation current is applied;

a multi-phase stator 503 carrying several armature windings 507 which are star-connected or delta-connected in the most common case of a three-phase structure and which provide converted electrical power to the rectifier bridge, working as an alternator.

The bridge is connected to the various phases of the armature and is mounted between ground and the battery supply terminal. This bridge has, for example, diodes connected to MOSFETs.

Operation in the motor mode of such an alternator is accomplished by forcing, for example, DC in the field magnet and supplying in a synchronous manner to the stator phases 120 ° phase shifted signals, perfectly sinusoidal or possibly trapezoidal or square.

This rectifier bridge in the alternator mode, and the control system in the engine mode, are piloted by the control unit. The power unit, formed by the rectifier and control bridge, and the control unit is a control and power module built into the outside of a rotating electrical machine, to which it is connected via an electrical connection element to the stator phase output terminals.

Moreover, means are provided for monitoring the angular position of the rotor so that, when operating as an electric motor, the electric current is injected at the right moment into the corresponding stator winding.

These elements, preferably of the magnetic type, sending information to the control unit are described, for example, in FR-2 807 231 and FR 2 806 223.

These elements thus comprise an object 750 rotatably mounted on the rotor or pulley 701 of the machine and at least one Hall effect or magnetic resistive sensor 752 detecting the passage of an object, preferably of the magnetic type.

Preferably, at least three sensors 752 are provided, they are carried by a front 713 or rear 504 bearing plate of the rotating electrical machine to support the stator continuously and rotate the rotor.

PL 210 932 B1

The sensor holder 753, here made of plastic, has portions 755 with an axial orientation. These portions 755 extend through bearing plate 504 via an opening 754. Sensors 752 are attached to portion 755 and are positioned radially between object 750 and blades 505 being very close to object 750. The sensor holder is mounted on mounting bolt 757.

The electrical connections of the sensors 752 are secured in the sensor holders 753 attached by two lugs 756 to the bottom of the rear end bearing 504 on the side opposite the object 750 and rotor 743.

The brush holder 716 is attached to the same surface of the bottom of the rear end bearing 504 by means of bolts and eyes not marked.

Brush holder 716 includes, as is known, two brush guide cages cooperating each with one replaceable commutator ring 706, 707 at the rear end of shaft 502. The brushes are acted upon by springs disposed in the cages.

It is desirable in some cases to improve the starting performance of the alternator-starter. So, it is possible to overexcitation the rotor to obtain a higher breakaway torque.

This overexcitation may be accomplished by an overvoltage at the excitation winding terminals and / or an overcurrent in the field winding with respect to a conventional alternator.

This can be accomplished by an electronic booster circuit that overexcites the rotor winding only when operating as a starter.

Here, this machine has the structure of a classical alternator, for example of the type described in EP-A-0 515 259, to which reference will be made in more detail.

The impellers 741, 742 have holes to press in on the shaft 502. More specifically, the shaft 502 is harder than the impellers 741,742 for mounting the wheels on the knurled portions.

The shaft 502 runs on both sides of the rotor 743 and forms a subassembly therewith.

The impellers, via their flanges, have a fan 515 with blades 505 mounted on them, here by electric welding.

The machine thus has internal ventilation (air-cooled), its rotor having at least one of its axial ends with a fan 515. In a variant, the machine is water-cooled.

More specifically, the rotor is a lobed rotor 743 with rotor wheels 741, 742 having on its outer periphery teeth of an axial orientation and a trapezoidal shape. The teeth of one impeller face the teeth of the other impeller, these teeth being generally trapezoidal in shape and overlapping from one impeller to the other.

Of course, as described for example in FR-A-2 793 085, permanent magnets may be placed between the teeth of the rotor to increase the magnetic field.

The rotor has an excitation winding between the flanges of its impellers. This winding includes an electrically conductive element which is wound to form turns. This winding is an excitation winding which, when active, magnetizes the rotor to form magnetic poles with the aid of the teeth. Each end of the rotor winding is connected to one commutator ring where a brush slides on each. The brushes are housed in brush holders attached to a rear machine bearing plate having in the center a ball bearing rotatably supporting the rear end of the shaft to which the rotor is attached.

The front end of the shaft is rotatably supported by a ball bearing 711 located in the front end bearing 713 of the machine. Outside the machine, the front end of the shaft carries a pulley 701 belonging to a motion transmission device including at least one drive belt connected to the pulley. The motion transmitting device provides connection to a pulley and a member, such as a second pulley, rotatably driven by the internal combustion engine of the vehicle.

Moreover, the rear cover 511 is mounted on the rear end bearing 504, in particular to protect the brush holder, so that these frequently replaced elements are better protected and easier to insert.

When the machine - here the alternator-starter - works as an alternator, i.e. as an electric generator, pulley 701 is rotatably driven by the vehicle's internal combustion engine via at least one of the belts. When the machine is operating as a starter, that is, as an electric motor, a pulley rotates the engine of the vehicle via the belt.

The front and rear bearing plates, with openings for internal ventilation of the machine, are connected to each other, e.g.

To be mounted on a solid surface in a vehicle. This housing permanently carries the stator on its outer periphery, usually formed by a bundle of sheets 508 provided with slots for mounting stator coils or more generally windings, the outputs of which are connected to said rectifier and control bridge.

The stator coils or windings are formed by wires or rod windings as described, for example, in WO92 / 06527; the bars may have a rectangular cross-section.

The stator comprises a rotor whose brushes are connected to the alternator regulator to maintain the alternator voltage at the required level, here, for example, of the order of 14 volts for a 12 volt battery.

The control and power module and the regulator are here mounted in an electronic housing situated outside the rotating electric machine. The controller can also be integrated into the control unit of the control and power module, which is located outside. The housing contains commutation elements containing power switches, a control unit, and an overexcitation circuit. The overexcitation system is active when operating as a starter to obtain the maximum starting torque of the alternator-starter and easier to start the internal combustion engine, also called a heat engine, of the car, either when starting a cold or when restarting, for example after stopping at a red light, the engine has been cut off to reduce fuel consumption and to perform the function known as "Stop and GO.

This overexcitation system receives as input the on-board mains voltage supplied by the battery and / or the alternator and supplies the excitation winding terminals with a voltage higher than the on-board mains voltage.

The regulator may contain elements that allow, in the event that the alternator-starter discharges to the on-board network while disconnected from the battery (the case of "load dump in the English terminology generally used by a specialist), to actuate the immediate opening of the power switch that supplies the excitation winding to quickly demagnetize the alternator, especially its rotor.

A power unit is now classically implemented in which the rectifier bridge comprises power transistors switched on to form a circuit breaker bridge, and in which the transistors are synchronously controlled by the current flowing in the alternator armature winding (synchronous rectification). However, it is necessary to pilot the transistors with a relatively complicated control unit such as, for example, a microcontroller, current sensors detecting the direction of the current in the alternator armature winding, an imaging bridge, etc. One of these rectifier bridges is described in the patent application FR-A-2 806 553 This rectifier bridge is shown in Fig. 1. It comprises three branches B1, B2, B3 having at least two transistors each, connected each between the alternator-starter phase $ 1, $ 2, $ 3, the power supply Ua of the on-board network and ground GND. Each transistor T1 T6 is piloted by control unit U1 to U6. These control units U1 to U6 form the group of control units of the power unit formed by the bridge of the circuit breakers. Each of these control units is provided for comparing the alternator phase voltage with the reference voltage and for controlling one of the rectifier bridge transistors as a function of the comparison result. Each of the control units comprises elements separate from those of the other units and intended to implement different units in a separate manner, comparing and compensating for reference voltage variations so that each unit only requires a signal having variations such as phase voltage and variations such as reference voltage. Each control unit U1 to U6 controls the power transistor T1 to T6.

This control unit, like most control units currently known, requires a significant number of electronic components since one control unit is required for one rectifier transistor.

The components used to make the power unit are thus arranged and connected on the first electronic board and form the power stage.

The components used to make the control unit are placed and connected on a second electronic board.

The two electronic boards that make up the control and power module are connected to each other by electric wires. Well, the electrical connection of these two plates requires a large number of connections between the two stages. Consequently, the control and power modules are relatively large, requiring them to be housed in a separate housing, separate from the housing containing the alternator-starter electromechanical assembly.

So, unlike conventional alternators which are completely integrated in the same housing, the alternator-starter requires two housings, i.e. a housing containing the alterPL 210 932 B1 itself and a housing containing the control and power module. The alternator-starter therefore requires more space than the conventional alternator. Moreover, it causes additional difficulties for the user in the car, since it is the car designer who has to connect the two housings together.

The essence of the invention

The object of the invention is to alleviate these limitations of the prior art. To this end, the invention proposes a control and power module miniaturized and which can be integrated into the housing of the alternator-starter. This module comprises a power unit in which the transistors of the same branch of the rectifier bridge are piloted by a driver placed adjacent to the transistors and controlled by a management circuit which may be at a distance from the driver. So the invention has the advantage that it reduces the length of the connections between the controllers and the power unit. Some of these connections are used for measurements, for example voltage measurements in a power unit, reducing the length of these connections to be measured will ensure good measurement accuracy by eliminating the parasitic noise that occurs with long connections.

The controller of the control unit according to the invention can pilot several transistors simultaneously, i.e., transistors of the same branch of the rectifier bridge. This driver therefore has the advantage of being small while still implementing a large number of functions. Due to its relatively small size, it can be placed in the power stage close to the transistors of the power unit it is piloting.

The alternator-starter control and power device according to the invention is characterized in that it comprises: a first stage integrated with said alternator-starter, which is formed of a plurality of compact, integrated electronic power sub-modules, each said electronic power sub-module being located at the level of a corresponding phase output of the stator-starter winding, and a second stage formed by the housing which is different from the mentioned electronic power sub-modules and includes a management system, each said power sub-module comprising a branch of said power transistor bridge and a driver that controls all of the power transistors of said branch and is located as close as possible to said power transistors, said management circuit controlling the operation of said set of drivers and together with it constitute said control unit .

Preferably, the controller comprises, on a first side, connections to the management circuit, and on the second side, connections to the power unit.

Preferably, the second stage is housed in the housing outside the alternator-starter.

Preferably, the commands of the manager are common to all controllers.

Preferably, each transistor is an array of parallel connected transistors.

Explanation of the figures of the drawing

The subject matter of the invention is shown in the exemplary embodiments in the drawing, in which:

Fig. 1, already described, schematically shows a control and power module of the prior art.

Fig. 2 shows a control and power module according to the invention.

Fig. 3 shows various connections of a controller in a control unit according to the invention.

Fig. 4 shows the electrical connections between the controller and the transistors of the power unit it is piloting.

Fig. 5 shows how the control and power module according to the invention is integrated into the rear of the alternator-starter housing.

Fig. 6 shows a front view of an embodiment of the power module according to the invention.

Fig. 7 shows a section view along the line AA of Fig. 6.

Fig. 8 shows a cross-sectional view of a power module in accordance with another embodiment.

Figures 9 to 11 show the ground connection method of the embodiments corresponding to figures 6 to 8.

Fig. 12 shows another embodiment of the invention.

Fig. 13 shows a cross-sectional view of a rear end shield containing power electronic modules according to the invention.

Fig. 14 shows an example of the fan shown in Fig. 13.

Figures 15, 16, 17 and 17a show the connection methods of the outputs of the electronic modules made at the cover level.

Figures 18 and 19 show a rear axial view of the cover of the electrical machine.

Fig. 20 shows a prior art alternator-starter.

Figures 21 and 22 show an embodiment of the modules shown in figures 7 and 12.

PL 210 932 B1

Fig. 23 shows a sectional view of Fig. 12.

Embodiments of the Invention

In the figures, identical or similar items will be designated with the same reference numerals. The reference on-board voltage Ua may also be designated B +.

Fig. 2 shows a control and power module 100 according to the invention connected to an alternator-starter. More specifically, Fig. 2 shows a 3-phase alternator-starter, each phase φ1, φ2 and φ3 of which is connected to one of the branches B1, B2 and B3, respectively, of the power unit 1. Each of the 3 branches of the rectifier or control bridge constituting the power unit 1 is identical. Consequently, only the branch of BI will be described in detail below.

The branch BI of the rectifier bridge 1 comprises two switches 11 and 12 which, in the invention, are power transistors. Transistor 11 is a "high side BI branch" transistor. It is connected between the phase φ1 of the alternator-starter and the supply Ua of the car's on-board network. Transistor 12 is a "low side BI" transistor. It is connected between the phase φΐ of the alternator-starter and the ground line GND.

The control and power module comprises a control unit 50 having, on one side, drivers 10, 20, 30, each piloting the power transistors of the same branch, and preferably, these drivers compare the alternator-starter phase potentials φ, φ2 and φ3 with the ground potential of the rectifier bridge. for controlling the transistor 12 and with the output potential Ua of the rectifier bridge for controlling the transistor 11, and on the other hand, a circuit that manages the 2 drivers 10, 20 and 30.

The branches of the rectifier bridge as well as the drivers that pilot them form the first stage 100b of the module according to the invention. The management circuit 2 forms the second stage 100a.

The driver 10 is connected, at the output, to the gates of the two transistors 11 and 12. This driver 10 is itself connected, via its input, to the manager 2.

Each controller 10, 20 and 30 is controlled by the same management circuit 2. Therefore, each controller receives different input signals from management circuit 2. These signals are shown in Fig. 3.

These signals fall into two categories:

- signals shown on the left side of the controller: these are signals coming from the management system; and

- the signals shown on the right side of the driver: these are signals received or transmitted from to the power unit, i.e. to the transistors that the driver controls.

One of the signals received from the management system is the additional power supply, denoted ALG, which is the supply voltage supplied by the auxiliary source to the gates of transistors 11 and 12. The controller also receives, from the management system, signals from the SC sensor, which are information provided by the rotor position sensors a starter-alternator for determining the position of the rotor of a rotating electrical machine. The control system also supplies the controller with information VD confirming the operating mode of the starter and information VA confirming the operating mode of the alternator. These last two signals enable the controller to discern whether the alternator-starter should be running, at that exact moment, as an alternator or as a starter.

In figure 3, the signals received and sent to the power unit are also shown, i.e. to the transistors 11 and 12 of the rectifier bridge. The controller receives the supply potential Ua of the alternator-starter, that is, the supply potential of the on-board network. It also receives the information MUa which is the potential measurement input of this line Ua. The controller outputs a signal GHS which is the gate control signal of the power transistor 11. The controller also receives a PH input from the alternator-starter as well as the MPH measurement of the phase input potential. The controller also outputs the GLS control of the gate of the power transistor 12. Finally, the controller receives the ground potential GND as well as the MGND measurement of the ground potential.

In Fig. 4, there is shown the controller 10, 20, 30 of the control and power module 100 according to the invention, with its various components and its various connections. In this figure 4, the alternator-starter 3 supplies the phase signal φ to the low side 12 and high side 11 transistors as well as the PH inputs of the controller. It also provides the phase measurement to the controller 10 at its MPH input.

In this figure 4, the measurement inputs MPH MGND and MUA are shown on the left side of the controller to simplify the figure. Practically, as shown in Fig. 3, these three inputs are located on the right side of the controller, i.e. on the side of the power unit.

Transistor 12 is connected to ground GND as well as to the controller MGND input. Transistor 11 is connected to the voltage Ua line as well as to the driver input MUa.

PL 210 932 B1

Two comparators C11 and C12 are connected, respectively, between the inputs MUa and MPH and between the inputs MPH MGND of the controller. The output of the comparator C11 provides a comparison value between the phase value MPH and the reference voltage value MUa. The output of the comparator C12 provides a comparison value between the phase value MPH and the mass value MGND. These comparison values ​​are then numerically processed by logic 13 to conclude whether the gate of transistor 11 and / or the gate of transistor 12 should be charged and / or discharged. The gates G11 and G12 of the power transistors 11 and 12, respectively, are charged and / or discharged by the current sources SU and S12, respectively. The current sources SU are made, for example, of two transistors SHC and SHD. The power sources S12 are made, for example, of two transistors SLC and SLD. So, each transistor is a current source.

The ALG input has an elevated potential given by the manager 2 to accurately charge the gate of the power transistors 11 and 12 via current sources S11 and S12. This ALG potential may be, for example: ALG = Ua + 16 volts.

The operation of the controller of Fig. 4 is as follows: in the starter operation mode, position sensors located on the rotor of the alternator-starter, which operates as a synchronous machine, determine the position of the rotor. The signals of the sensors are sent to the management system 2, which processes them and sends them to the inputs SC of the controllers. The gates G11 and G12 of transistors 11 and 12 are driven as a function of the signals received at the input SC via logic 13 and current sources S11 and S12.

In the alternator mode, the power transistors 11 and 12 work as synchronous rectifiers, i.e. comparators C11 and C12 detect the phase level at the input MPH, in relation to the ground potential at the input MGND and the output potential at the input MUa. The result of this comparison is fed to gates G11 and G12 via logic 13 and power sources S11 and S12.

The operating mode as an alternator or a starter is selected on the controller by the corresponding logic inputs VA and VD. For example, when alternator mode is selected, input VA receives logic 1 and input VD receives signal 0, and vice versa when starter mode is selected. For example, logic level 1 is 5 volts and logic level 0 is zero voltage.

The measurement inputs of the MPH phases, the MUa potential and the MGND ground make it possible to avoid the influence of disturbances generated by the currents that flow in the connections PH, Ua and GND. These disturbances can be caused, for example, by the resistance of the connections between the elements with each other or on the backing of the electronic board.

Each controller is placed near the potentials PH, VA, GND for measurement, measurement inputs MPH, MVA, MGND use connections with a reduced length, which also reduces the sensitivity of these inputs to interference that can be transmitted through these connections, which explains the advantages of the proposed architecture according to the invention.

On the other hand, the management circuit 2 can be remote from the controllers because it transmits only low-critical potentials (ALG power, logic levels VA, VD, SC) against the measurement inputs (MPH, MVA, MGND).

The gates of transistors 11 and 12 should allow feeding of potentials higher than the output potential Ua of the alternator-starter. For this purpose, the control system supplies terminal ALG with voltage Ua + 16 volts, +/- 1, which enables powering gates G11 and G12 of transistors 11 and 12. If the voltage at terminal ALG is not sufficient, power transistors 11 and 12 are open.

Operation of the control and power module 100 according to the invention will now be described. At rest, i.e. when the car is stopped and when the contact key is open (i.e. not turned in the ignition switch lock), transistor 11 is open while transistor 12 is closed. This condition is obtained when both logic inputs VD and VA are at level 0. When the car's engine is stopped and the contact key is open, the management system 2 is inactive and cannot supply a voltage of Ua + 16 volts to the ALG input of the controller. Consequently, a voltage is applied to the gate G12 of transistor 12, the minimum value of which is Ua - 1 volts.

In other words, when the key is open and VD and VA are 0, the gate voltage of transistor 11 is less than or equal to 0.2 volts and the gate voltage of transistor 12 is greater than Ua - 1 volts. In other words, transistor 12 is closed while transistor 11 is open, which keeps the stator potential at ground potential.

The current drawn by the controller under these conditions is less than 10 microamps at 25 ° C.

When the car is stopped and when the contact key in the ignition lock is turned (i.e. the contact key is closed), the control system 2 is started. The control system 2 is therefore active and can supply voltage Ua + 16 volts at the ALG control input 8

PL 210 932 B1. Under these conditions, the potential of the gate G11 of transistor 12 is limited to 15 +/- 1 volts. In other words, when the key is closed and VD and VA are 0, the gate voltage of transistor 11 is less than or equal to 0.2 volts and the gate voltage of transistor 12 is 15 +/- 1 volts.

In starter operation, the confirmation inputs VD and VA are no longer both equal to 0. In starter mode, the signal input SC also appears. So, in the starter operation mode, the rectifier bridge works as an inverter. Each branch of the rectifier bridge is synchronized with the SC sensor signal applied to the respective driver. Inverter operation mode is obtained when VD equals 1 and VA input equals 0.

So, if SC = 0 and VA = 0 and VD = 1, the gate voltage G11 of transistor 11 is less than 0.2 volts and the gate voltage G12 of transistor 12 is 15 +/- 1 volts. Conversely, if SC = 1 and VA = 0 and VD = 1, the gate voltage G11 of transistor 11 is 15 +/- 1 volts and the gate voltage G12 of transistor 12 is less than 0.2 volts. The control and power circuit 100 therefore operates as an inverter, the voltages indicated indicate that the phases Ph1, Ph2 and Ph3 lie in the rotor position as a function of the signals SC1, SC2 and SC3 provided by the position sensors after being processed by the management circuit 2.

In alternator operation, the rectifier bridge works as a synchronous rectifier. This function is activated when the confirmation input VA is equal to 1 while the input VD is equal to 0. In this case, the comparators C11 and C12 of the controller compare, on the one hand, the phase voltages PH with the voltage Ua, and on the other hand, the phase voltage PH with the potential GND ground. The result of the comparison makes it possible to open and / or close the transistors 11 and 12 working in synchronism with the currents flowing in the armature winding of the alternator-starter. The result at the gates of transistors 11 and 12 is as follows:

- If PH> Ua and VD = 0 and VA = 1, the gate voltage G11 of transistor 11 is 15 +/- 1 volts and the gate voltage G12 of transistor 12 is lower than 0.2 volts, and consequently: transistor 11 is closed and transistor 12 open.

- If Ua> PH> GND and VD = 0 and VA = 1, the gate voltage G11 of transistor 11 is less than 0.2 volts and the gate voltage G12 of transistor 12 is also less than 0.2 volts, and consequently: transistors 11 and 12 they're closed.

- If GND> PH and VD = 0 and VA = 1, the gate voltage G11 of transistor 11 is lower than 0.2 volts and the gate voltage G12 of transistor 12 is 15 +/- 1 volts and consequently: transistor 12 is closed and transistor 11 open.

In the classic rectifying mode, the control system 2 can control the opening of all power transistors 11, 12, 21, 22, 31 and 32 of the rectifier bridge to prevent synchronous rectification. This mode of operation is obtained when the two confirmation inputs VD and VA are at logic level 1. Rectification is then performed using diodes specific to the MOS transistor technology.

In the case where VD = 1 and VA = 1, the gate voltage G11 of transistor 11 and the gate voltage G12 of transistor 12 are each lower than 0.2 volts.

The gate voltages of the power transistors 11 and 12 are controlled by DC sources, not shown in the figure for simplicity. The closure control is effected by a gate load current of e.g. 100 milliamps, and the opening control is effected by a gate discharge current of e.g. 400 milliamps.

Fig. 5 shows an example of integrating a control and power module according to the invention into the rear of the alternator-starter. Indeed, the fact that one driver is used to control two transistors of the same rectifier branch makes it possible to reduce the number of connections to the management unit 2.

In particular, the controller is implemented such that, on the one hand, it only comprises connections to the power unit and, on the other hand, only connections to the management circuit 2. In this way, the controller can be easily switched on in the vicinity of the power transistors it is piloting. Moreover, in this embodiment, only four connections are necessary between the controller and the manager 2, three of these four connections are moreover common to all controllers. So it is easy to separate the managing chip of the 2 controllers. The size of the manager 2 as a result of this separation will thus be very markedly reduced. The management system 2 can therefore be integrated with other car accessories.

In the example of Fig. 5, the control and power module 100 is integrated into the rear of the alternator-starter. In Fig. 5, the rear face of the alternator-starter with its phase and rotor outputs is shown. In the case of Figure 5, each driver is located close to the power transistors they control, the assembly being located close to one of the alternator-starter phase outputs. For example, the driver 10 is enabled just off the transistors 11 and 12 of the branches B1 of the rectifier bridge, the transistor and driver assembly is located near the phase output φ> 1 of the alternator-starter. Also, driver 20 and transistors 21 and 22 of branches B2 of the rectifier bridge are located near the phase output φ2, and the driver 30 and branch transistors B3 are located near the phase output φ3 of the alternator-starter.

In the example of Fig. 5, each branch of the rectifier bridge includes several high side transistors and several low side transistors. Indeed, in the classical case, several transistors (often 2 to 4) are switched on in parallel to form a larger power transistor. Regardless of whether there is only one power transistor or several transistors connected in parallel, the operation is identical to that just described.

The end of the shaft 4 (shown schematically as a wheel in Fig. 5) that carries the rotor of a rotating electrical machine includes position sensors 5 that provide indications of the rotor position to the management system 2. This rotor position information is processed by the management system 2 then sent to it. SC inputs of controllers 10, 20 and 30.

Preferably, the connections made between the management unit 2 and the various controllers form an arc of a circle around the shaft 4 carrying the rotor.

In the case of Fig. 5, the control and power module 100 is integrated in the housing of the alternator-starter. This unit can also be integrated with other car accessories, such as the battery charge management housing.

It is also possible to integrate only the power unit with the respective controllers 10, 20, 30 and to arrange the management circuit 2 in a casing external to the alternator-starter. For example, the management circuit 2 may be integrated in the battery housing or in the battery management housing or also in the receiver management housing (control member).

In another embodiment, the control and power module 100 is integrated in an independent housing, external to the alternator-starter but more compact than in the prior art.

Fig. 6 shows an embodiment of the first stage 100b of a control and power module 100 according to the invention. As previously described, this first stage comprises, for each rectifier branch corresponding to one stator phase, a measurement and control controller 10 as well as two power transistors. So, considering the first branch of the rectifier or drive bridge, we have driver 10 as well as the two power transistors 11 and 12 previously described.

According to the invention, this first control and power stage is preferably implemented in an independent housing. The three branches of the bridge are identical, so it is possible to use an identical power enclosure for each branch of the bridge.

As shown in Fig. 6, which shows the first stage of the control and power module in a front view, the power electronics 11 and 12 are arranged in metal tracks 104.

Preferably, the technology used is a technique called chip or bare chip assembly, in which a subassembly without a protective housing is directly attached to the board. Indeed, this electronic housing located under the hood of the car is subject to high thermal stress and the use of components in the plastic housing should be avoided here. Advantageously, it is therefore preferable to use components in a metal housing or components mounted by a technology called chip assembly or in which the component is mounted on a metal track. The network obtained by the set of metal tracks is what is called a lead-out frame.

In order to control the winding phases of an electric machine in the starter mode, it is necessary to inject very strong currents. These currents can be as high as around 1000 amps when the instrument is operated on the on-board mains voltage, traditionally around 12 volts.

Thus, the low side and high side transistors 11 and 12 can be formed by connecting at least two power transistors 11a, 11b and 12a, 12b in parallel, respectively.

Preferably, the power module 100b comprises a thermistor 102 (temperature sensor) accessible via connections TH1, TH2.

The controller 10 is subjected to temperatures well below that of the power transistors. The same is true for paths carrying control signals or ALG, SC, VD, GLS, GHS, TH ... functionalities previously described.

PL 210 932 B1

The control of the alternator-starter, in which there are very strong currents, presents a great number of conceptual problems for the skilled person to implement small-sized control and where the current distribution and temperature distribution inside the module are balanced.

Thus, according to the invention, each module corresponding to one branch of the bridge is connected to each of the phases and works independently without conducting currents from the other modules. So the path carrying the output Ua is connected in one place to the power conductor which groups the currents from all the modules. Each of the modules therefore works independently, without the currents belonging to the other modules being conducted or disturbed. On the other hand, the power transistors 11a and 12a are preferably connected perfectly symmetrically in the metal track with respect to the phase input φΐ. Thus, a perfectly balanced flow of currents is obtained. Also for high side power transistors 12a and 12b which are mounted in their metal track as symmetrically as possible for the same reasons. It is very important not to disturb the balance of currents in power transistors which should run in parallel with identical currents. So, to obtain a well current balanced power module according to the invention and as shown in Fig. 6, the low side and high side power transistors are mounted as perpendicular to each other as possible. This configuration further has the advantage that it realizes all connections by wire welding without any covering on any signal or power paths. Thus, all connections are made with short lines 101, which has the advantage that a surely resistant module is obtained, especially against vibrations. Indeed, the car's environment is highly vibrating and the bonded cables are subjected to severe vibrations that may break it and cause the alternator-starter system to malfunction. The maximum reduction in the length of the connecting cables increases their resonant frequency, which makes them insensitive to vibrations applied to the power module.

As stated previously, the object of the invention is to realize a control for an alternator-compact starter with high cooling power, while having high operational reliability over time.

In order to implement such a power module capable of conducting currents up to about 1000 amperes, some solutions have been proposed in the art.

The power module could be implemented in the known technology with a DBC (Direct Bounded Copper) substrate, which contains three layers. The first layer is a metal track engraved to form electrical connections, the second intermediate layer is a plate of an electrically insulating material such as ceramics, for example alumina, and the third layer is a metal plate formed by copper or nickel-plated copper. Thus, a copper-alumina-copper layered structure is obtained.

The DBC substrate assembly and the brazed or bonded power electronics are in turn soldered onto the copper plate to form a mechanical base and heat sink. In this technology, the copper tracks are thin in order to conduct high currents, it is necessary to significantly increase the track surface which increases the size of the power module very much. Moreover, this technology is not suitable for applications where there are strong currents because the heat capacity offered by the small thickness of copper is not sufficient. On the other hand, it is very difficult to implement particular shapes, such as rounded shapes, which are particularly suitable for integration in applications such as, for example, the back of a rotating electric machine due to the fragility of alumina. On the other hand, alumina has little resistance to vibrations such as occur inside a car's engine block.

The substrate may also be of the SMI (Insulated Metal Substrate) type. In this case, the ceramic plate is replaced by a resin plate capable of carrying the first layer constituting a very thin copper metal track. The third heat dissipating layer may in this case be a metal plate of aluminum or copper.

When the substrate used is a DBC substrate, the power module is strong and transmits high power, but the production cost is increased. For SMI type substrate, the cut metal track may be more complex and more power electronics can be placed on it, but the module is less resistant to high powers and severe environmental stresses. However, it is possible with SMI technology to add an additional copper surface between the chip and the thin copper metal track to allow better heat dissipation. This solution, which is complex to implement, is not very satisfactory from the economic point of view.

PL 210 932 B1

In both of these cases, the thermal path between the power electronics and the cooling elements of the external power module is long as it requires the passage of at least the plurality of substrate layers that the two technologies contain.

The object of the invention is to alleviate the disadvantages of conventional power modules by presenting a power module which is cheaper to manufacture and whose structure allows efficient cooling by means of external cooling elements and with a small number of thermal connections to be overcome.

So, as shown in Fig. 7, the power module includes power metal tracks 104 for receiving, for example, power sub-assemblies 11a and 11b connected to the stator winding phase output of the electrical machine. The same metal track may also carry a thermistor 102 to estimate the temperature of the module. The power module as previously described may include other power metal tracks 104. So as shown in Fig. 7, another power metal path carries a power sub-assembly 12 connected to the + Ua output in this embodiment.

Preferably, the metal tracks are realized from the same conductive metal plate in which the metal tracks are realized, for example, by extrusion. Advantageously, in order to obtain a compact module according to the invention, the metal tracks made of a metal plate, preferably copper, have a large thickness for the passage of high currents. So the thickness of the tracks can vary between 0.6mm and 2mm. The techniques mentioned do not make it possible to obtain a track of this thickness on the substrate itself. Indeed, the thicknesses normally used for the making of the tracks are not much more than 400 µm. For obvious reasons, it is not contemplated to realize a path of this thickness by classical engraving operations.

In order to ensure a good arrangement of the paths in relation to each other, metal bridges are realized during the stamping operation.

Obviously, these metal bridges will be removed during the shunt removal operation that will be performed at the end of the process.

Advantageously, in order to simplify the design of the power module, low-power metal tracks intended, for example, for control signals, can also be made of this high-thickness metal plate, and their arrangement is also made of metal bridges. The set of metal tracks forms a frame with external leads.

In order to obtain a frame with outer leads having good mechanical cohesion, it is necessary to fit it with the jig to form the base. Moreover, this base should be able to efficiently dissipate the heat emitted by the flow of strong currents. Thus, according to the invention, it has been proposed to inject the resin 107 into the free spaces between the metal tracks. This operation can easily be performed by placing a frame with outer leads between the two plates constituting the injection mold. So, after the resin injection operation is completed, all the gaps between the tracks are filled with the resin. The bypass removal operation may be performed at the end of this operation.

Preferably the resin will be of the thermoplastic type such as PPS (polyphenylsulfide) or PA 6.6 (polyamide 6.6) or PBT (polybutylene terephthalate). PPS also has the advantage of being non-flammable (UL94V0 standard).

To increase the mechanical cohesion of the base formed by the frame with the outer leads and the resin, the molds may include holes so that the resin locally covers the metal tracks on the small piece 140 as shown in Fig. 8. In the same vein, the edge of the metal tracks may have special shapes such as 141 slant for better resin fixation.

After the shunt removal operation, the components, in particular the power components, can be secured to metal tracks, for example by soldering in a heating process by a laser or by an oven (convection or infrared). This brazing enables electrical and thermal contact between the component and the metal track.

Thus, according to the invention, and as shown in Fig. 8, a power electronic module is obtained in which metal tracks, in particular carrying the power components 117, are accessible from the outside through surfaces 114 opposite the component bearing surfaces.

The base of the power module according to the invention is realized such that at least the metal power tracks are partially accessible on their top and bottom surfaces, the top surface is designed to receive the power electronic subassembly, and the bottom surface 114 is designed to cooperate with a cooling device such as a heat sink 113 shown. in Fig. 7. Preferably, portions of the surfaces of the lower metal tracks are accessible facing the power components

They carry on their opposing upper surfaces in order to obtain good cooling of the power components.

In order to ensure a good thermal contact between the surface 114 and the upper surface 115 of the heat sink 113, it is provided to arrange an preferably flexible heat conductor and non-electrically conductive element 108 in order on the one hand to dissipate heat well and, on the other hand, to electrically insulate the metal tracks between them. Such an element may, for example, be a glass fabric impregnated with epoxy or polyamide (TVI) resin or with a phase change thermoplastic thermoplastic resin. The thermally conductive and electrically insulating material has two adhesive surfaces or a thermally conductive adhesive 108 comprising glass spheres forming conductive spacers. Phase change resin has the advantage that it melts when exposed to heat. So if the heat sink or the bottom surface of the power module has an uneven surface, the phase change resin can fill the unevenness. Preferably, the paths leading to the output of the module for external connection preferably have an elbow 118 directed upwards of the module so as to be spaced apart from the top surface 115 of the heat sink 113.

Such a module, corresponding to each branch of the bridge, can be produced in very large quantities. In this case, it will have a very high mechanical cohesion while maintaining the ability to dissipate heat. Thus, as shown in Fig. 7, it is envisaged to place under the power module a metal plate 109 forming a base with a ground potential. This base is held in an insulating ring 110 preferably formed by molding. Due to the mechanical parameters, this ring is preferably made of PPS. The cover is mounted on this ring and is also PPS for the same reasons.

The cover is fastened, for example, by screws 119 which penetrate the ring 110. In other embodiments, the cover can be fastened, for example, by gluing or by welding elements such as ultrasonic or friction welding.

Inside the power module, under the cover 105 of the power module, a filler material 120 can be arranged to fill the free space around electronic components and between wire connections of the wire bonded type, for example. This filler material 120, in addition to its sealing function, has the advantage of enhancing the mechanical cohesion of the base formed by the metal tracks and the surrounding resin.

In the embodiment shown in Fig. 7, the electrical insulator and the heat conductor are disposed between the metal base 109 and the bottom surface 114 of the metal tracks. As previously described in Fig. 8, this electrical insulator 108 and the thermal conductor may be TVI or a phase change thermoplastic thermoplastic resin.

Preferably, this insulation is glued onto two surfaces, on the one hand towards the metal tracks and on the other side towards the metal base 109. Thus, this base provides effective protection of the opposite side of the metal tracks and allows a module with good mechanical cohesion and easy handling to be obtained.

This base 109 is made of heat-conducting material and forms part of the heat sink by contacting the bottom surface 114 of the cooled metal tracks.

As shown in Fig. 7, the protrusion 106, preferably extending from the material of the protective cover 105, abuts against at least one metal track. In the case where the filler material 120 is inserted over the electronic components, the filler material is located around the protrusion.

This protrusion on the one hand provides a good mechanical cohesion of the power module assembly by forming a rigid module, and on the other hand, the protrusion which presses against the metal track when the cover is attached, for example by screwing, causes a slight bulging 121 of the bottom surface 122 of the metal power module base.

Thus, according to the invention, this bulging of the bottom surface 122 of the power module also causes good heat dissipation to the heat sink. Indeed, when the power module is secured, for example, by screwing onto the heat sink 113 at the level of the bolt holes 111, the bulge provides a perfect flattening of the power module at the heat sink 113 under the twisting pressure, ensuring good electrical contact between the base 109 and the heat sink 113. The bolt hole 111, which is aligned in the embodiment with the hole 112 in the base, could also be made by molding its top of PPS to resist twisting forces.

In a variation, a thermally conductive material such as TVI may be sandwiched between the heat sink and the power module. In this case, the ground connection will be made by an electrical connection element, such as a clamp, connecting the base 109 at the level of the opening 112 to the connection cover, this member passing through the cover opening 606, for example. Of course, this terminal will be electrically insulated from the heat sink 113.

In a variation, protrusion 106 may be replaced by a wall or portion of a wall formed on a portion of the path during the ring forming operation 110. Of course, the height of the wall will be determined such that the operation of securing the cover 105 will exert sufficient pressure on the wall to cause a slight bulge in the base 109.

The power components 11a and 11b are connected between ground and the phase output of the stator winding. In starter operation, they conduct very high currents. Ground connections should be as short as possible to minimize heating. One solution is, for example, to bring the plates of mass to the ring 110 and make connections to the plates. However, the length of these wires will be quite long.

Another approach shown in Fig. 7 is to gain mass directly from the base metal plate 109.

In the first embodiment, as shown in figures 9 and 10, the beads 123 are formed on the base. These beads are designed to receive the connecting leads 126 to form a power circuit. These connections are preferably of the bonded wire type. When carrying out the resin molding at the level of the metal track, it is of course necessary to provide resin-free holes 124 to provide an upward transition to the plate or bead 123. Also, insulation 108, such as the aforementioned TVI, should preferably be slit to be placed around the plates 123. This configuration has the advantage of having short connecting wires.

In a variation and as shown in Fig. 11, the opening in the resin 107 and in the insulation 108 is made in such a way as to directly reach the metal base 109 as the mass. This solution makes it possible to eliminate the lumps 123.

Fig. 12 shows an embodiment of a power module 250 for an alternator-starter that integrates all the power electronics of the three branches of the control and rectifier bridge of the alternator-starter. So the marking 200 shows the power sub-module. This submodule corresponds to the power electronics of one branch of the bridge dedicated to one output of the phases of the stator winding of the electrical machine. The frame with the outer leads of each of these sub-modules corresponds for example to that described in Fig. 6.

This embodiment has the advantage of being economical, on the one hand, in terms of the number of elements to be placed on the cooling device and, on the other hand, in terms of assembly shortages.

Preferably, each of these sub-modules is separated by a wall 201. This wall 201 as well as the peripheral ring 110 are preferably made during the same molding operation. Preferably, these walls and this ring close the connecting terminals 202 and 203. As shown in Figures 7 and 12, the terminals 203 oriented upwards of the module differ from the ground plates 203a, the B + plates 203b or Ua corresponding to the voltage of the on-board network and the plates 203c for low signals. power. The terminals 202 are oriented towards the power metal 104 and control 130 tracks. These terminals 202 are connected to said metal tracks by wire connections of the bond type. In order to connect the metal power paths to the corresponding terminals 202, it is envisaged to make several wire connections in parallel to conduct the current without excessive heating.

The power amplifiers 205 are directly connected to the output conductors of the stator winding phases. The tips 205 are subjected to the forces of vibration during the operation of the rotating electrical machine. The wire connections 204 that connect the terminal 205 through the terminal 202 correspond to a mechanical and thermal disconnection with the power sub-module which contributes to the reliability of the power module.

The terminals 202 extend upwards to be accessible at the level of the plates 203. Preferably, the terminals 202 and 203 are provided directly from the metal tracks of the frame subassembly with the outer leads of the electronic module. These metal tracks are of great thickness, the tips 203 have a high stiffness which makes them easy to place for external connection, for example by means of a cover 511 containing metal tracks.

Such a module can be directly mounted on an external heat sink 13.

In a first embodiment of assembly, it is provided to fasten, for example by screwing, the ring 110 to the walls 201 on the outer radiator.

PL 210 932 B1

In three areas, each dedicated to the sub-modules 200, a thermal and non-conductive spacer is placed on the external heat sink. Preferably, said spacer 108 is an adhesive comprising glass beads, the glass beads acting as spacers to provide a constant thickness between the top surface of the heat sink and the power submodules. A base formed by a frame with outer leads and a thermoplastic resin corresponding to each of these sub-modules is then applied to this adhesive. Of course, any other thermal and electrically insulating spacer such as TVI or double-sided adhesive tape may also be suitable. In one embodiment, this base corresponds to the base described in Fig. 8 except that it does not include a formed ring 110. In this embodiment, the power metal tracks 104 make direct contact with the cooling device through the thermal spacer which contributes to good heat dissipation and consequently a small number of thermal surfaces to pass. In a variant, gluing of subassemblies as described in figures 7 or 8 may also be considered.

Preferably, each of these sub-modules is tested prior to mounting on an external cooling device.

When the sub-modules are attached to the external cooling device, wire connections 204 are made between the metal tracks 104, 130 and the ends of the internal connections 202.

At this stage of the power module assembly process, each of these sub-modules is preferably coated with a gel 120 designed to seal the chips and connections against moisture and external contaminants.

The cover 105 is finally put on the top of the ring 110, in front of the tip 203, the cover includes holes for these terminals 203 to pass through the cover for connection to power signals (phase outputs or on-board network + Ua) or to the control signals of the management unit 2 .

Such an arrangement corresponding to Fig. 12 is shown in section in Fig. 23.

A power module 250 as shown in Fig. 12 has a rectangular shape. Of course, this module may be shaped like a circular segment to fit, for example, to the rear of a rotating electrical machine. It is possible to make a circular shape thanks to the technology of making the frame with external power inlets previously described.

As shown in Fig. 12, the power module 250 makes it possible to obtain insulated ground via the terminals 203a positioned in the ring 110. The advantage of the insulated mass is especially justified when switching strong currents that disturb the grounds of other electrical equipment. For each branch of the bridge, there may be one or more ground terminals 203a. Preferably, as the B + terminal 203b, one ground terminal 203u is used to balance the currents well.

In this case, the two ground terminals 202a will be connected in a molded ring to make the connection as close as possible to the transistors and one ground terminal 203a to the outside.

This preferred assembly method, in which the modules tested previously (bridge branches) are fastened, has the advantage that it is very economical in view of the shortcomings compared to a process in which all the chips that make up the three-branch bridge assembly will be soldered in one operation. In the case where the heat sink is electrically insulated from the rear end shield, the heat sink is an insulated mass which is connected to the battery ground either directly or via the car body. In this configuration and in the second embodiment of incorporating the electronics into one power module as shown in Fig. 12, ground terminals 202a and 203a are removed and are replaced by ground connections similar to those described in Figures 9 to 11 and wherein the base 109 is replaced. through the top surface of the heat sink 113.

Fig. 13 shows a cross sectional side view of an alternator-starter with integrated electronics including the control and rectification electronics according to the invention. As with all known alternator-starters, the alternator-starter shown in Figure 13 includes a rotor 743 mounted on rotating shaft 502. This rotor 743 is held by a stator 503 provided with an armature winding 507. The stator 503 supports a rear end shield 504 and a front end shield (not shown) that support the rotating shaft 502 via bearings 506.

As previously explained, the alternator-starter comprises a power MOS rectifier bridge connected to the power transistor control units. The rectifier bridge and control units form the electronic power unit of the alternator-starter. This power electronics is mounted on the top surface of the heat transfer bridge 113 in one or more power modules 100b previously described.

PL 210 932 B1

Preferably, the module 100a containing the management unit 2 is also mounted on the top surface of the heat sink for good cooling. This management unit 2 preferably comprises a control system for managing, on the one hand, the starting mode, restarting as a starter function and, on the other hand, voltage regulation as an alternator function. This unit may also include the excitation stage of the rotor winding, which also requires good cooling.

According to the invention, for a good cooling of the power modules 100b made as one or more modules, the surface axially oriented towards the rear bearing plate of the electric machine of this heat dissipating bridge 113 forms the wall of the longitudinal or radial passage of the cooling medium flow 517 in the alternator-starter. The second wall of this passage 517 is thus formed by the top surface of the rear end shield 504. The bottom surface of the heat sink 113 includes ribs 518 forming ventilation channels 517.

The protective cover 511 includes radial openings 519 preferably located opposite the flow passage 517. In this way, a coolant, and in particular air, is introduced to the rear of the starter alternator through the openings 519 and then flows through the passage 517 under the diffusion bridge 113, cooling the power electronics 100b. as well as module 100a. A fan 515 with blades 505, mounted on the rotating shaft 502 or on the rotor 743, ensures that the air is sucked into the passage 517.

For more effective cooling, the fan 515 can preferably form a dual composite fan wherein at least one blade of the first fan is positioned between at least two blades of the second fan as shown in Fig. 14. So, as shown in Fig. 14, fan 515 comprises according to of the present invention, at least two fans 515a, 515b, hereinafter referred to as the first fan and the second fan, respectively. The second fan 515b is arranged to be fastened, e.g. in a manner known by spot welding or riveting, to the respective axial end 530 (face) of the pole wheel 742 of the rotor 743 of Fig. 13.

Here, the fans 515a, 515b are metal being economically profiled from sheet metal. Each fan respectively comprises a flange portion 515c, possibly circular as flat as possible, which is provided with a circular central hole 515d for the passage of the rotor shaft 502, and a set of ventilation blades extending axially from the flange 515c and including ventilation channels therebetween, which in this embodiment are outward divergent.

The first fan 515a includes a first set of blades, referred to as primary blades 515e, while the second fan 515b includes a second set of blades, referred to as secondary blades 515f.

Thus, preferably at least two consecutive blades of one of the fans include at least one blade of the other fan.

The primary blades 515e are in an embodiment radially shorter than the secondary blades 515f.

The blades 515e and 515f have approximately the same radial length, the same shape, and the same axial size such that the blades are generally identical except for the two primary blades 515g which are radially shorter than the other blades 515e.

The blades 515e, 515f, and 515g are located at the outer periphery of the respective flange 515c.

Primary blades 515e, 515g are disposed here, each between two secondary blades 515f.

This arrangement makes it possible to increase the power of the fan and reduce the risk of detachment of the cooling flow from the blade. Indeed, if the air separates from the secondary blades 515f, the primary blades 515e, 515g direct the extracted air onto the secondary blades 515f. Thus, each primary vane 515e, 515g is built-in, i.e., positioned, in the ventilation passage 515h between two adjacent secondary blades 515f, and which expands from the inner circumference to the outer circumference of the vane. In this embodiment, at least one primary blade is thus interposed between two successive secondary blades.

The primary blades 515e, 515g and the secondary 515f are here obtained by cutting and bending from the respective metal flange 515c and preferably having a curved shape.

So the diverging channels are defined in part by the outer circumference of one of the flanges and by the blades.

The primary and secondary blades have a large radial length and are therefore very efficient in terms of ventilation. Preferably, the blades 515e, 515f and 515g have a radial length greater than their axial height.

PL 210 932 B1

In an embodiment, the blades are flat having a radial orientation, the fan being centrifugal. In a variant, the blades are inclined with respect to the axial and / or radial direction. In a variation, the blades are axially higher than the radially long.

The flange 515c has, on its outer periphery, inclined portions cut, advantageously economically on the press, which, when bent beyond the plane of the flange 515c, become bent blades. More specifically, the blades have a radially arc-shaped cross section.

Primary blades 515e are designed to reduce the noise of the electric machine while increasing the output and efficiency. This is so that the primary blade compresses the coolant to keep it in contact with the secondary blades 515f. This counteracts air recirculation and eddies, and the air flow is more laminar with low friction and noise. This solution makes it possible, if necessary, to remove the front fan (not shown) located on the front pole wheel of the rotor, so that the alternator has only one fan in the alternative.

Of course, various combinations of the arrangement of the secondary blades 515u and the primary blades 515e, 515g may also be considered.

So, you can put several primary vanes between the secondary vanes. The number of primary blades positioned between the secondary blades within the same ventilation device 515 may be constant or variable. Here, one secondary vane is located between two adjacent secondary vane, i.e. consecutive.

Also, consider having several consecutive secondary blades 515f with no primary blades in between.

The distribution of the primary and secondary blades is determined by the function of the electric machine to be cooled to obtain the best cooling with minimal aerodynamic noise.

Primary blades 515e may be angularly distributed uniformly, as in the case shown in Fig. 14, in a non-uniform manner. The non-uniform distribution is obtained in an embodiment having some blades having a length different from the other blades 515g of Fig. 14.

The uneven arrangement enables a greater reduction of the noise of the running fans. Also, the secondary blades 515f may have a non-uniform angular distribution as shown in Fig. 13. Thus, a set of non-uniform blades is obtained divided into two parts with respect to one side of the fan.

In a variant, a heat insulating element, such as a heat insulating covering, is provided between the two flanges 515c of the first and second fans, the first fan 515a in this case being fiber-reinforced plastic. The blades 515e, 515f, 515g extend axially in the same direction and perpendicular to the plane of the collar 515c.

In a variant, the blades may be inclined and curved with respect to the corresponding plane of the flange as described in FR A 2 602 925.

The angular indexing element is inserted between the two flanges 515c for a good angular position and therefore a good orientation of the primary blades with respect to the secondary blades. To do this, each collar 515c has a cutout 515k on its inner circumference. The 515k cutouts are identical here. So it is enough to apply the notches with a roller, for example, to obtain a good angular position. The fan assembly is then secured, for example by welding or riveting, to form an assembly that is easy to handle and transport.

Preferably, the first flange has at least one projection such as a hole or cutout shown in dashed lines as 515m enabling the second flange to be secured to the rotor of the machine, for example by welding or riveting. Preferably, several openings or cutouts are provided.

In a variant, each flange is attached to the rotor, for example, by welding.

The blades 515e, 515f and 515g are assumed to be all axially at the same height here, i.e. the free edges of the blades are in the same transverse plane. More specifically, the blades 515e, 515g have an axial height less than the blades 515f, the width difference being equal to the thickness of the first flange 515c.

In an embodiment, the blades 515e, 515f are axially different in height, the blades 515f protrude, for example, axially with respect to the blades 515e, 515g. As a result, not all of the free edges of the blades are in the same plane.

In all cases, it is possible to fit the cover 515p on the free edges of the blades 515e, 515f and 515g or on the free edges of the blades furthest from the flange 515c as shown in Figure 16 of FR A 2 811 156 and as shown in part by the broken line in Figure 14.

PL 210 932 B1

In a variant, at least one blade of one of the fans is provided with a blade overhang extending inclined or perpendicular to the plane of the flange of the fan in question as described and shown in FIGS. 11 to 13 of FR A 2 811 156. In general terms, the invention allows obtain the same configurations of two sets of blades with different dimensions as in the mentioned document FR A 2 811 156 and in a simple and economical manner. For example, at least one blade, and preferably at least several blades, of at least one of the fans may be undulated or have an axially tapering height, or be flat and inclined with respect to the radial direction as shown in Figures 6, 15 and 2 of this document. .

By means of this ventilation device 515, load loss and noise are reduced, air efficiency and flow are increased, and a stable coolant flow is obtained, thus ensuring effective cooling of the power and control modules 100a and 100b.

Thus, a ventilation device is obtained which has a complex configuration of the blades, which provides the possibility of increased cooling at a relatively low cost of manufacture, while having good mechanical strength.

More detailed information is provided in French patent application FR 03 02 425 filed on February 27, 2003.

So the made bridge scattering 113 creates a mezzanine over the rear end shield 504.

According to the invention, the dissipation bridge 113 comprises, on its lower surface, cooling fins 518. These cooling fins are arranged in the passage 517 and ensure that the cooling medium flows in a chosen path, i.e. in such a way that the medium flows as close to the rotating shaft as possible in order to better sweep. the lower surface of the scattering bridge. Thus, the bottom surface of the spreading bridge is cooled preferably over the entire radial distance between the outer circumference and the inner circumference close to the shaft of the spreading bridge. Adjacent ribs define radial channels that guide coolant through passage 517. Thus, these channels include a bottom surface formed by a rear end bearing, two opposite sides of two adjacent ribs as well as a U-shaped bottom of the diffusion bridge formed between two adjacent ribs.

Preferably, the heat sink 113, including fins 518 on its lower surface 113b, and on its upper surface 113a, the control and power module (s) 100a, 100b, is one block. In a variation, the heat sink 113 carrying the power modules 100b is mounted on the device with fins to form a two-piece diffusion bridge.

This medium then flows through the outlets 504a-504d in the rear end shield 504. These outlets 504a-504d are preferably identical to the outlets in the alternator endshield shown in Figure 20. Preferably, the ribs 518 are arranged radially in the direction of flow. the fluid converge towards the center outlets 504b and 504c of the rear end shield 504. Thus, air (or other coolant) is sucked from the side of the alternator-starter and flows towards the center outlets 504b and 504c of the bearing plate 504, thereby flowing around the diffusing means, i.e. the ribs 518, for their entire front length before exiting through the side outlets 504a. and 504d of end shield 504. Thus, the power electronics 100b is cooled by conduction and convection, after the diffusion bridge 113 has cooled, through the fins 518.

Moreover, since the diffusion bridge 113 and the power modules 100b are not adjacent to the rotating shaft, there is preferably a space 522 between the rotating shaft 502 and the diffusion bridge 113 through which air can also pass. This space 522 forms an axial channel for the flow of the medium. In an embodiment of the invention, the outlets 523a and 523b are formed in the protective cover 511. The air is thus drawn through the inlets 523a and 523b to the alternator-starter, then it flows through the space 522 along the rotating shaft 502 and reaches the flow passage 517 under the dissipation bridge 113 which improves the cooling of the radiator 113. In this way, the power electronics are cooled, on the one hand, on the side through passage 517 and on the other side axially through space 522. This additional axial air flow through space 522 further enables better cooling of the alternator internals, such as the brush holder cage or the faces of the armature windings, by increasing the total air flow of the machine.

The path of coolant flow downstream of the alternator-starter is shown by arrows F and broken lines in Figure 13.

In a preferred embodiment of the invention, deflectors 524 are positioned downstream of the outlets 504a and 504d formed in the rear end bearing 504.

PL 210 932 B1

These deflectors 524 make it possible to distance the flow of the intake medium so that the medium flowing from the alternator-starter is not directly returned to the passage 17. Thus, significant recirculation of the heat medium coming from inside the alternator-starter is avoided.

Deflectors 524 may be mounted on the bearing plate 504 near the side outlets 504a and 504d of the bearing plate. They can also be made in the protective cover 511, for example, on the rounded end of the protective cover as shown in Fig. 13.

In the embodiment shown in Fig. 13, the protective cover 511 covers the entire rear portion of the alternator-starter, i.e. it covers the power electronics 100b, 100a mounted on the diffusion bridge 113 and the entire rear bearing plate 504. In this case, the protective cover 511 may include outlets located downstream of the side outlets of the rear end shield and intended to allow the refrigerant to drain away from the alternator-starter. It may also include, in addition to or in place of the outlets, deflectors 524. These may be provided in the cover itself.

The protective cover 511 may also cover the power electronics mounted on the dissipation bridge and the upper portion of the bearing plate 504, that is, it does not cover the sides of the bearing plate containing the outlets 504a and 504d. In this case, the deflectors can be mounted on the bearing plate 504 or also made on the rounding of the end of the cover.

As shown in Fig. 13, the fan 515 carries at the axial end of at least one portion of the blades 505 a cover 515p. This cover forces the airflow F to flow at the level of the fan blade 505 which provides better cooling of the stator winding fronts 507 and electronics carried by the heat sink.

Preferably, the outer side 525 of the outlets 504b and 504d formed in the rear end shield 504 is possibly directly in front of the inner edge of the blade 505 so as to force the entire cooling flow F to pass between the fan blades 505. Thus, only the residual flow can flow between the top of the cover 515p and the lower axial surface of the rear end shield 504.

Preferably, the outlets 504b and 504d are proximate the seat of the bearing 506 so that it can be efficiently cooled all the more if the fan is an overlay of two fans as previously described.

In the first embodiment, and as shown in Fig. 13, the heat sink 113 is electrically insulated from the rear end shield 504. Thus, the heat sink 113 is an insulated mass especially for the power electronics located on the management electronics module (s) 100b 2. Electrical isolation of the heat sink from the rear end shield allows better performance in terms of electromagnetic and thermal compatibility.

In the first embodiment, the dissipation bridge 113 is attached to the rear end shield 504 by means of electrically insulated and preferably thermally non-conductive assembly strippers 527, thus constituting a thermal barrier with respect to the heat generated by the stator.

Preferably, the pullers 527 are the same as those normally used to secure the bearing plate 504 to the stator magnet 503. An electrically insulating nut 527b is interposed between the lock nut 527a and the top surface 113a of the heat sink 113. A strut 527c including a projection 527d is positioned between the bottom surface 113b the heat sink and the outer surface axially of the rear end bearing 504.

In a second embodiment, the heat sink 113 is connected to the rear bearing plate 504 in an electrically insulated manner by means of a screw 528 whose head is oriented towards the bottom surface of the axial bearing plate 504. In this embodiment, an electrically non-conductive strut 528a is interposed between the bottom surface 113b of the heat sink. 113 and the axially upper surface of the rear end bearing 504. The bolt 528 abuts against an electrically insulating bushing with a boss located in the axial thickness of the rear end bearing 504.

Of course, other elements for attaching the heat sink to the bearing plate may be contemplated.

Of course, struts 527c or 528a may be attached to the spreading bridge 113 or bearing 504 to provide the mounting terminals.

In this case, electrical and thermal insulation elements such as insulating washers should be placed at the end of these fixing plates.

The heat sink carrying the power control electronics is thus spaced from the outer surface of the axial bearing plate of the rear rotating electrical machine to constitute a mezzanine cooled by air introduced substantially radially between the mezzanine and the top axial surface of the rear bearing plate.

PL 210 932 B1

In the embodiment described in Fig. 7, the power module 100b is grounded through a direct electrical contact between the base 109 and the top surface 113a of the heat sink.

A ground lead 529, electrically connected to the heat sink by a fastening 529b such as bolting or welding, is preferably connected to the negative terminal of the car battery to provide an insulated ground.

As previously described, the terminals 203 corresponding to the signal or control connections from the power module or modules 100b are oriented axially towards the rear of the electric machine for making electrical connections. Preferably, these terminals 203 reach a plastic cover 511 that is embedded in power and control metal tracks. Preferably, the cover includes all metal tracks allowing all connections to be made between the power modules on the one hand and the power modules 100b on the other hand and the management unit 2. So, this arrangement has the advantage that no wire connections are made under the cover, which gives non-negligible economic benefits. Indeed, all the low and high power connections are made in one pass at the level of mounting the cover equipped with metal tracks. By removing the line connections under the cover, space is gained, thus, for example, reducing the axial length of the machine.

Figures 15 and 16 and 17 and 17a show elements of possible electrical connections between the terminals 203 and the metal tracks 600 contained in the molded cover 511.

As shown in Fig. 15, tip 203 passes through an opening 601, closed or semi-closed, provided in path 600 to be connected. Preferably, the end of the tip 203 extends from the other side of the track 600 for fastening by welding. The reference number 602 therefore shows the welding performed.

Preferably, the end 605 of the tip 203 is possibly at the same axial height, preferably at a height less than the top axial edge of the cover 511 to avoid welding damage when handling the electric machine. Metal tracks are accessible through the holes 606 made in the tailgate 511.

Tip 203 is shaped to tolerate placement tolerances.

Fig. 16 shows a variant of the electrical connection between the tip 203, preferably of the power, and the metal track, which are connected by a screw-nut type screw. In a known manner, a Grover 608 spring washer is positioned between the underside of the head and the outer surface of the metal track while the tip 103 is clamped between the nut and the underside of the metal track. In this embodiment, preferably, a portion 611 of the cover 105 of the module 100b including one or three sternum branches contacts nut 607 for pivoting thereof at the end of screwing.

Fig. 17 shows a joint made by welding as described in Fig. 15 containing a coating of the varnish, glue or silicone type to avoid a harmful chemical attack such as salt fog or moisture. This cover is also fitted to the bolt-nut fastener described in Fig. 15.

Fig. 17a shows a joint made by L laser welding in which the tip 203 does not pass through the metal path. In this case, path 203 has a curve 610 adapted to contact metal path 600 under tension when cover 511 is mounted on the back of the electric machine. This embodiment has the advantage that the cover 511 is airtight.

Fig. 18 shows the rear cover according to the invention in a rear view of a rotating electrical machine. This embodiment corresponds to the case where the mezzanine heatsink 113 is electrically insulated from the rear end shield 504. So preferably, cover 511 includes only one high power metal track 600a that can conduct approximately 1000 amps during the actuation phases. This metal track 600a, which preferably includes the 650B + connection of the brush holder, and is intended for the positive terminal B + connected to the electrical mains of the car, can therefore be designed to take up all the space that is necessary without disturbing the second ground terminal 600b necessary when the mezzanine is not insulated. and as shown in Fig. 19.

As shown in figures 18 and 19, it is therefore very easy to connect the controllers 10, 20 and 30, positioned centrally close to the rotating shaft, with the management module 2 previously described. Thus, according to the invention, it is possible to obtain an alternator-starter type electrical machine comprising, on its rear and mechanically connected bearing plate, all the power, control and control electronics necessary for its operation. Of course, depending on the case, electronic functions may

To the outer casings without leaving the framework of the invention. The architecture of the rear end bearing as described previously also allows a very good cooling of the power module or modules thanks to the mezzanine structure cooled by the coolant introduced simultaneously radially and preferably axially. This cooling is all the more efficient if the power electronic module (s) are made according to figures 6 to 12.

The integration of the power electronics on one or more modules, preferably connected via tracks provided on the cover, thus permits particularly easy and cost-effective mounting of the power electronics and / or alternator-starter control. In addition, the integration of metal power paths in the lid allows the connector 630 to be easily positioned anywhere in the lid to match the configuration of the car.

Fig. 19 is a second embodiment of a cover 511 comprising metal traces according to the invention for a heat sink to form a mezzanine with the same electrical potential as the rear end shield 504. In this case, the power modules are electrically isolated from the heat sink. In this embodiment, it is not necessary to electrically insulate the spacers 527c or 528a forming the attachment terminals previously described. Thus, electrically insulating washers or sleeves located at the end of the mounting plates or between the mezzanine and the rear end plate may be omitted making the mezzanine rear end plate assembly mechanically more rigid.

In this embodiment, the integrated cover, in addition to what is described in Fig. 18, has a power path 600b dedicated to ground. To achieve junction 630, the two power paths 600a and 600b overlap in an area 652 of the cover which preferably has an increased thickness at this location so that two paths can be traced there. At this point, the routing of the path will be made in such a way as to provide electrical isolation. To make a crossing, at least one of the two paths will have at least one folded portion.

In this embodiment, the brush holder ground connection 651 is also preferably made through ground path 600b.

As shown in figures 18 and 19, a connector 653 is also provided for communication with an external electronic housing, for example via a known protocol like Can, Lan, Lin, BSP or via a simple wired connection.

Preferably, filter capacitors 653, as shown in Fig. 19, may be connected via cover 511. Capacitors 653, soldered between the power paths Ua and ground, are tightly connected to the cover by, for example, molding, crimping, gluing. In the same way, you can place capacitors between the metal tracks of a low power cover.

Figures 21 and 22 show two embodiments of an alternator rear end plate integrating control and monitoring electrical circuits in the spreading end shield 113 forming the mezzanine of the present invention.

In these two figures, the mounting tips 528a are not electrically insulated so that the spreading bearing disk 113 is not electrically insulated. The masses of the electronic modules 100b are thus connected at the terminals 203a.

Fig. 21 corresponds to the power electronics 100b distributed over three modules, each corresponding to one bridge branch and as described in Fig. 7, while Fig. 21 corresponds to a power electronics circuit connecting the three bridge branches on one module as described for Fig. 13.

In these two figures, the reference 100a shows the location for the management module 100a 2 which also has connection terminals 203c.

As shown in Fig. 21, the power terminals 203a and 203b are connected such that they are electrically connected in a single pass, for example at the level of the metal tracks of the cover 511 as previously described.

Screws 680 inserted into sockets 111 of the power modules 100b, for example, secure the mounting of the power modules on the heat sink 113.

PL 210 932 B1