Vehicle control apparatus

The present invention relates to a vehicle control device mounted on a vehicle.

Vehicles have been developed in which the engine is stopped based on a predetermined stop condition and the engine is restarted based on a predetermined start condition (see Patent Document 1). In the vehicle described in Patent Document 1, when the engine is stopped based on the stop condition, the alternator is generated to charge the lithium ion battery and the lead battery. On the other hand, when the engine is restarted based on the starting conditions, the starter is started and rotated by the electric power of the lead battery.

<p num="0003"><patcit num="1"><text>Japanese Unexamined Patent Publication No. 2014-36557</text></patcit></p>

<p num="0004"> By the way, when the starting condition is satisfied and the engine is restarted, if an abnormality occurs in the starting system such as the starter, the battery and the controller, it is difficult to restart the engine. However, even if an abnormality occurs in the starting system, it is required to restart the engine from the viewpoint of ensuring the minimum running performance.</p><p num="0005"> An object of the present invention is to restart the engine even when an abnormality occurs in the starting system.</p>

<p num="0006"> The vehicle control device of the present invention is a vehicle control device mounted on a vehicle, and includes a first electric motor connected to an engine and a first power storage body connected to the first electric motor. A second starting system including a starting system, a second electric motor connected to the engine, and a second power storage body connected to the second electric motor, and the engine is stopped based on a stop condition, and the start condition is set. Based on the above, the first engine control unit includes an engine control unit that restarts the engine using the first starting system, and the engine control unit stops the engine based on the stop condition. When an abnormality occurs in the starting system,<u style="single">Before the start condition is satisfied</u>The engine is restarted using the second starting system.<u style="single">Further, the vehicle control device of the present invention is a vehicle control device mounted on a vehicle, and includes a first electric motor connected to an engine and a first power storage body connected to the first electric motor. A second starting system including a first starting system, a second electric motor connected to the engine, and a second power storage body connected to the second electric motor, and the engine is stopped and started based on a stop condition. An engine control unit that restarts the engine using the first starting system based on conditions, an energization path that connects the positive terminal of the first storage body and the second storage body, or the first storage body. The conduction state provided in the energization path connecting the negative electrode terminal with the second power storage body and connecting the first electric motor and the first power storage body is separated from the first electric power storage body and the first power storage body. The engine control unit has a shutoff state and a switch that can be switched to, and the engine control unit is in a state where the engine is stopped based on the stop condition, and when an abnormality occurs in the first starting system. Restarts the engine using the second starting system after the shutoff signal for switching the switch to the shutoff state is output.</u></p>

<p num="0007"> According to the present invention, when an abnormality occurs in the first starting system under the state where the engine is stopped based on the stopping condition, the engine is restarted using the second starting system. As a result, the engine can be restarted even if an abnormality occurs in the starting system.</p>

<figref num="1">It is a schematic diagram which shows the structural example of the vehicle provided with the control device for a vehicle which is one Embodiment of this invention.</figref><figref num="2">It is a block diagram which shows the structural example of the control device for a vehicle.</figref><figref num="3">It is a circuit diagram which showed the structure of the control device for a vehicle simply.</figref><figref num="4">It is a diagram which shows the relationship between the terminal voltage of a battery and the charge state.</figref><figref num="5">It is a timing chart which shows an example of the power generation control of a motor generator.</figref><figref num="6">It is explanatory drawing which shows the electric power supply state of the control device for a vehicle.</figref><figref num="7">It is explanatory drawing which shows the electric power supply state of the control device for a vehicle.</figref><figref num="8">It is explanatory drawing which shows the electric power supply state of the control device for a vehicle.</figref><figref num="9">It is explanatory drawing which shows the electric power supply state of the control device for a vehicle.</figref><figref num="10">It is explanatory drawing which shows the occurrence example of the abnormal state in the 1st start system.</figref><figref num="11">It is explanatory drawing which shows the occurrence example of the abnormal state in the 1st start system.</figref><figref num="12">It is explanatory drawing which shows the occurrence example of the abnormal state in the 1st start system.</figref><figref num="13">It is a flowchart which shows an example of the execution procedure of a fail-safe control.</figref><figref num="14">It is explanatory drawing which shows the engine restart situation by fail-safe control.</figref>

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view showing a configuration example of a vehicle 11 provided with a vehicle control device 10 according to an embodiment of the present invention. As shown in FIG. 1, the vehicle 11 is equipped with a power unit 13 including an engine 12. A motor generator (first motor) 16 is connected to the crankshaft 14 of the engine 12 via a belt mechanism 15. In this way, the motor generator 16 is mechanically connected to the engine 12. Further, the transmission mechanism 18 is connected to the engine 12 via a torque converter 17, and the wheels 20 are connected to the transmission mechanism 18 via a differential mechanism 19 or the like. Further, the power unit 13 is provided with a starter motor (second motor) 21 for starting and rotating the crankshaft 14. In this way, the starter motor 21 is mechanically connected to the engine 12.

The motor generator 16 is a so-called ISG (integrated starter generator), and not only functions as a generator driven by the crankshaft 14 to generate electricity, but also functions as an electric motor for starting and rotating the crankshaft 14. The motor generator 16 includes a stator 22 provided with a stator coil and a rotor 23 provided with a field coil. Further, the motor generator 16 is provided with an ISG controller 24 including an inverter, a regulator, a microcomputer, and the like in order to control the energized state of the stator coil and the field coil. A sensor 24a that detects the generated voltage and generated current of the motor generator 16 is connected to the ISG controller 24.

When the motor generator 16 functions as a generator, the energized state of the field coil is controlled by the ISG controller 24. By controlling the energized state of the field coil, the generated voltage of the motor generator 16 can be controlled. Further, when the motor generator 16 is driven to generate electricity, the generated current of the motor generator 16 can be controlled by controlling the inverter of the ISG controller 24. On the other hand, when the motor generator 16 functions as an electric motor, the energized state of the stator coil is controlled by the ISG controller 24. The ISG controller 24 controls the energized state of the field coil and the stator coil based on the control signal from the control unit 50 described later.

Subsequently, the configuration of the vehicle control device 10 will be described. FIG. 2 is a block diagram showing a configuration example of the vehicle control device 10. FIG. 3 is a circuit diagram showing the configuration of the vehicle control device 10. As shown in FIGS. 1 to 3, the vehicle control device 10 includes a lithium ion battery 27 which is a first storage body and a lead battery 28 which is a second storage body. The lithium ion battery 27 and the lead battery 28 are connected in parallel to the motor generator 16. The first power supply line 29 is connected to the positive electrode terminal 27a of the lithium ion battery 27, and the second power supply line 30 is connected to the positive electrode terminal 28a of the lead battery 28. Further, an energization line 31 is connected to the output terminal 16a that outputs the generated current of the motor generator 16. The first power supply line 29, the second power supply line 30, and the energization line 31 are connected to each other via a node 32 which is a connection point. That is, the positive electrode terminals 27a and 28a of the lithium ion battery 27 and the lead battery 28 are connected via an energization path 100 including a first power supply line 29, a second power supply line 30, and a node 32.

An open / close switch (switch) SW1 is provided on the first power supply line 29 constituting the energization path 100. Further, the second power supply line 30 is provided with an open / close switch SW2. The open / close switch SW2 is provided between the positive electrode terminal 28a and the node 32 in the second power supply line 30. These open / close switches SW1 and SW2 can operate in a closed state, that is, a conductive state (on state), and an open state, that is, a cutoff state (off state). That is, the open / close switch SW1 can be switched between a conductive state in which the motor generator 16 and the lithium ion battery 27 are electrically connected, and a cutoff state in which the motor generator 16 and the lithium ion battery 27 are electrically separated. Similarly, the open / close switch SW2 is switched between a conductive state in which the motor generator 16 and the lead battery 28 are electrically connected and a cutoff state in which the motor generator 16 and the lead battery 28 are electrically separated.

The instantaneous low protection load 33, the vehicle body load 34, and the like are connected to the second power supply line 30. Further, the starter motor 21 is connected to the second power supply line 30 via the starter relay 35, and the ISG controller 24 is connected via the ISG relay 36. Further, the second power supply line 30 is provided with a fuse 37 that protects the instantaneous low protection load 33, the vehicle body load 34, the starter motor 21, the ISG controller 24, and the like. In the illustrated example, the open / close switch SW1 is provided on the first power supply line 29, but the present invention is not limited to this. As shown by the alternate long and short dash line in FIG. 3, the open / close switch SW1 may be provided on the energizing line 38 connected to the negative electrode terminal 27b of the lithium ion battery 27.

That is, the negative electrode terminals 27b and 28b of the lithium ion battery 27 and the lead battery 28 are connected via an energization path 101 including energization lines 38 and 39. An open / close switch SW1 may be provided on the energization line 38 constituting the energization path 101. Even when the open / close switch SW1 is provided on the energizing line 38, the open / close switch SW1 keeps the motor generator 16 and the lithium ion battery 27 in a conductive state that electrically connects the motor generator 16 and the lithium ion battery 27. It can be switched to a cut-off state that electrically separates.

As shown in FIGS. 1 and 2, the vehicle control device 10 is provided with a first power supply circuit 41 including a lithium ion battery 27 and a motor generator 16. Further, the vehicle control device 10 is provided with a second power supply circuit 42 including a lead battery 28, a momentary low protection load 33, a vehicle body load 34, a starter motor 21, and the like. The first power supply circuit 41 and the second power supply circuit 42 are connected via the open / close switch SW2. Further, the vehicle control device 10 is provided with a battery module 43, and the lithium ion battery 27 and the open / close switches SW1 and SW2 are incorporated in the battery module 43.

The battery module 43 is provided with a battery sensor 44 that detects the charge state, discharge current, charge current, terminal voltage, temperature, and the like of the lithium ion battery 27. Further, the battery module 43 is provided with a battery controller 45 including a drive circuit unit, a microprocessor, and the like. The battery controller 45 is provided with a first switch control unit 45a for controlling the open / close switch SW1 and a second switch control unit 45b for controlling the open / close switch SW2. The battery controller 45 controls the open / close switches SW1 and SW2 based on a control signal from the control unit 50 described later. Further, the battery controller 45 opens the open / close switch SW1 to separate the lithium ion battery 27 from the vehicle control device 10 when an excessive charge / discharge current or temperature rise of the lithium ion battery 27 is detected. Although not shown, the battery controller 45 is connected to the second power supply line 30 in the same manner as the ISG controller 24 described above.

As described above, the instantaneous low protection load 33 is connected to the second power supply line 30. The instantaneously low protective load 33 is an electric device that needs to continue its operating state when the engine is restarted under idling stop control, which will be described later. Examples of the instantaneous low protection load 33 include engine accessories, brake actuators, power steering actuators, instrument panels, and various electronic control units. A vehicle body load 34 is connected to the second power supply line 30. The vehicle body load 34 is an electric device that allows a momentary stop state when the engine is restarted under idling stop control. Examples of the vehicle body load 34 include a door mirror motor, a power window motor, a radiator fan motor, and the like.

As shown in FIG. 2, the vehicle control device 10 includes a control unit 50 that controls a motor generator 16, a battery module 43, and the like. The control unit 50 is provided with a charge / discharge controller 51 that controls charging / discharging of the lithium ion battery 27. The charge / discharge controller 51 determines the charging state of the lithium ion battery 27, the operating status of the accelerator pedal and the brake pedal, and the like based on input signals from other controllers and sensors. Then, the charge / discharge controller 51 controls the charge / discharge of the lithium ion battery 27 by controlling the power generation state of the motor generator 16 based on the charge state of the lithium ion battery 27 and the like. The charge / discharge controller 51 includes a microcomputer composed of a CPU, ROM, RAM, etc., a drive circuit for generating control currents for various actuators, and the like.

The control unit 50 is provided with an ISS controller (engine control unit) 52 that executes idling stop control. The idling stop control is a control that automatically stops the engine 12 based on a predetermined condition and automatically restarts the engine 12 based on a predetermined condition. The ISS controller 52 determines the stop condition and start condition of the engine 12 based on the input signals from other controllers and sensors. Then, the ISS controller 52 automatically stops the engine 12 when the stop condition is satisfied, and automatically restarts the engine 12 when the start condition is satisfied. The stopping condition of the engine 12 is, for example, that the vehicle speed is equal to or lower than the predetermined vehicle speed and the brake pedal is depressed. Further, as the starting condition of the engine 12, for example, the depressing of the brake pedal is released and the depressing of the accelerator pedal can be mentioned. The ISS controller 52 includes a microcomputer composed of a CPU, ROM, RAM, etc., a drive circuit for generating control currents for various actuators, and the like. The ISS of the ISS controller 52 is an "idling stop system".

As sensors connected to the control unit 50, a battery sensor 53 that detects the charge / discharge current and the charging state of the lead battery 28, an accelerator sensor 54 that detects the amount of depression of the accelerator pedal, and a brake sensor that detects the amount of depression of the brake pedal. There are 55. Other sensors connected to the control unit 50 include a vehicle speed sensor 56 that detects the vehicle speed, which is the traveling speed of the vehicle 11, and a start switch 57 that is manually operated when the engine is started. Further, the control unit 50 is connected to a warning light 58 that notifies the occupants of an abnormality in the vehicle control device 10.

Further, the control unit 50, the motor generator 16, the battery module 43, etc. are connected to each other via an in-vehicle network 59 such as CAN or LIN. That is, the ISG controller 24, the battery controller 45, the charge / discharge controller 51, the ISS controller 52, and various sensors are freely connected via the vehicle-mounted network 59. The power generation voltage, power generation current, etc. of the motor generator 16 are input from the ISG controller 24 to the control unit 50 via the vehicle-mounted network 59, and the charge state, discharge current, etc. of the lithium ion battery 27 are input from the battery controller 45. To. Then, the control unit 50 determines the operating state of the vehicle control device 10 and the running state of the vehicle 11, and outputs a control signal to the ISG controller 24 and the battery controller 45.

[Battery voltage characteristics] Subsequently, the voltage characteristics of the lithium ion battery 27 and the lead battery 28 will be described. FIG. 4 is a diagram showing the relationship between the terminal voltage of the battery and the charging state SOC. The charge state SOC (state of charge) is a value indicating the degree of charge of the battery, and is a ratio of the remaining capacity to the design capacity of the battery. The terminal voltages V1 and V2 shown in FIG. 4 are the battery voltage when no current is flowing, that is, the open end voltage. The reference numeral GH shown in FIG. 4 indicates the maximum generated voltage of the motor generator 16.

As shown in FIG. 4, the terminal voltage V1 of the lithium ion battery 27 is set higher than the terminal voltage V2 of the lead battery 28. That is, the lower limit voltage V1L in the charge / discharge range X1 of the lithium ion battery 27 is set higher than the upper limit voltage V2H in the charge / discharge range X2 of the lead battery 28. Further, the terminal voltage V1 of the lithium ion battery 27 is set lower than the upper limit of the charging voltage (for example, 16V) of the lead battery 28. That is, the upper limit voltage V1H in the charge / discharge range X1 of the lithium ion battery 27 is set lower than the upper limit of the charge voltage of the lead battery 28. As a result, even when the lithium ion battery 27 and the lead battery 28 are connected in parallel, overcharging of the lead battery 28 by the lithium ion battery 27 can be avoided, and deterioration of the lead battery 28 can be avoided. it can. The charging voltage upper limit is an upper limit value of the charging voltage set for each type of the storage body from the viewpoint of suppressing deterioration of the storage body.

As shown in FIG. 4, since the lithium ion battery 27 has excellent cycle characteristics, the lithium ion battery 27 has a wide charge / discharge range X1. On the other hand, the lead battery 28 has a narrow charge / discharge range X2 near full charge from the viewpoint of preventing battery deterioration. Further, the internal resistance of the lithium ion battery 27 is set to be smaller than the internal resistance of the lead battery 28. That is, the internal resistance of the lead battery 28 is set to be larger than the internal resistance of the lithium ion battery 27.

[Motor generator power generation control] Subsequently, the power generation control of the motor generator 16 will be described. FIG. 5 is a timing chart showing an example of power generation control of the motor generator 16. FIG. 5 shows the generated voltage VG of the motor generator 16, the terminal voltage V1 and the charging state S1 of the lithium ion battery 27, and the terminal voltage V2 and the charging state S2 of the lead battery 28. Further, the brake ON shown in FIG. 5 means a state in which the brake pedal is depressed, and the brake OFF means a state in which the brake pedal is released.

As shown in FIG. 5, the charge state S1 of the lithium ion battery 27 is controlled within the charge / discharge range X1. For example, when the charging state S1 of the lithium ion battery 27 drops to the lower limit value SL with discharging, the motor generator 16 is controlled to the power generation state and the lithium ion battery 27 is charged. Here, the power generation state of the motor generator 16 includes a combustion power generation state and a regenerative power generation state. The combustion power generation state is a power generation state in which the motor generator 16 is generated by engine power and the fuel energy is converted into electric energy. The regenerative power generation state is a power generation state in which the motor generator 16 is generated when the vehicle is decelerated and the kinetic energy of the vehicle 11 is converted into electric energy. In order to improve the energy efficiency of the vehicle 11 and improve the fuel efficiency, it is necessary to reduce the combustion power generation state of the motor generator 16 and suppress the fuel consumption of the engine 12 by increasing the regenerative power generation state of the motor generator 16. desirable. That is, it is desirable to actively store the regenerated electric power of the motor generator 16 in the lithium ion battery 27 and release the regenerated electric power from the lithium ion battery 27 to the vehicle body load 34 or the like to reduce the combustion power generation state of the motor generator 16. ..

Whether or not to control the motor generator 16 to the combustion power generation state is determined based on the charge state S1 of the lithium ion battery 27. That is, the charge / discharge controller 51 controls the motor generator 16 to the combustion power generation state when the charge state S1 drops to the lower limit value SL. Then, the charge / discharge controller 51 continues the combustion power generation state of the motor generator 16 until the charge state S1 reaches the first upper limit value SH1. On the other hand, whether or not to control the motor generator 16 to the regenerative power generation state is determined based on the operation status of the accelerator pedal and the brake pedal. That is, the charge / discharge controller 51 controls the motor generator 16 to the regenerative power generation state when the vehicle decelerates when the accelerator pedal is released or when the brake pedal is decelerated. Then, when the accelerator pedal is depressed or the brake pedal is released, the charge / discharge controller 51 releases the regenerative power generation state of the motor generator 16 and controls the motor generator 16 to the power generation suspension state. There is. When the charging state S1 rises to the second upper limit value SH2 under the state where the motor generator 16 is controlled to the regenerative power generation state, the motor generator 16 is used to prevent overcharging of the lithium ion battery 27. The regenerative power generation state of is released, and the motor generator 16 is controlled to the power generation hibernation state.

[Power supply status of vehicle control device] Subsequently, the power supply status of the vehicle control device 10 will be described. 6 and 7 are explanatory views showing the power supply status of the vehicle control device 10. FIG. 6 shows the power supply status when the lithium-ion battery is charged, and FIG. 7 shows the power supply status when the lithium-ion battery is discharged.

First, as shown in FIG. 5, when the charge state S1 of the lithium ion battery 27 drops to the lower limit SL (reference numeral A1), the charge / discharge controller 51 controls the motor generator 16 to the combustion power generation state. In this combustion power generation state, the generated voltage VG of the motor generator 16 is raised to a predetermined voltage Va higher than the terminal voltage V1 of the lithium ion battery 27 (reference numeral B1). Here, as shown in FIG. 6, when the generated voltage VG of the motor generator 16 is raised above the terminal voltage V1 of the lithium ion battery 27, the open / close switches SW1 and SW2 in the battery module 43 are closed. Be retained. As a result, as shown by the arrows in FIG. 6, the generated power of the motor generator 16 is supplied to the lithium ion battery 27, the lead battery 28, the instantaneous low protection load 33, and the vehicle body load 34.

In this way, when the motor generator 16 is controlled to the combustion power generation state, the lithium ion battery 27 is charged, so that the charging state S1 of the lithium ion battery 27 gradually rises. Then, as shown in FIG. 5, when the charging state S1 reaches the first upper limit value SH1 (reference numeral A2), the charge / discharge controller 51 controls the motor generator 16 to the power generation hibernation state. In this power generation hibernation state, the power generation voltage VG of the motor generator 16 is lowered to 0, which is lower than the terminal voltage V1 of the lithium ion battery 27 (reference numeral B2). Here, as shown in FIG. 7, when the generated voltage VG of the motor generator 16 is lowered below the terminal voltage V1 of the lithium ion battery 27, the open / close switches SW1 and SW2 in the battery module 43 are closed. Be retained. As a result, as shown by the arrows in FIG. 7, the electric power stored in the lithium ion battery 27 is supplied to the instantaneous low protection load 33, the vehicle body load 34, and the lead battery 28.

Then, as shown in FIG. 5, when the brake pedal is depressed (reference numeral C1), the charge / discharge controller 51 controls the motor generator 16 to the regenerative power generation state. In this regenerative power generation state, the generated voltage VG of the motor generator 16 is raised to a predetermined voltage Vb higher than the terminal voltage V1 of the lithium ion battery 27 (reference numeral B3). Here, as shown in FIG. 6, when the generated voltage VG of the motor generator 16 is raised above the terminal voltage V1 of the lithium ion battery 27, the open / close switches SW1 and SW2 in the battery module 43 are closed. Be retained. As a result, as shown by the arrows in FIG. 6, the generated power of the motor generator 16 is supplied to the lithium ion battery 27, the lead battery 28, the instantaneous low protection load 33, and the vehicle body load 34.

After that, as shown in FIG. 5, when the brake pedal is released (reference numeral C2), the charge / discharge controller 51 controls the motor generator 16 to the power generation hibernation state. In this power generation hibernation state, the power generation voltage VG of the motor generator 16 is lowered to 0, which is lower than the terminal voltage V1 of the lithium ion battery 27 (reference numeral B4). Here, as shown in FIG. 7, when the generated voltage VG of the motor generator 16 is lowered below the terminal voltage V1 of the lithium ion battery 27, the open / close switches SW1 and SW2 in the battery module 43 are closed. Be retained. As a result, as shown by the arrows in FIG. 7, the electric power stored in the lithium ion battery 27 is supplied to the instantaneous low protection load 33, the vehicle body load 34, and the lead battery 28.

As described above, the charge / discharge of the lithium ion battery 27 can be controlled by controlling the generated voltage VG of the motor generator 16. That is, the lithium ion battery 27 can be charged by raising the generated voltage VG above the terminal voltage V1. On the other hand, the lithium ion battery 27 can be discharged by lowering the generated voltage VG below the terminal voltage V1. Moreover, since the terminal voltage V1 of the lithium-ion battery 27 is set higher than the terminal voltage V2 of the lead battery 28, the lithium-ion battery 27 can be charged and discharged while the open / close switches SW1 and SW2 are kept closed. it can. That is, since the lithium ion battery 27 can be discharged without disconnecting the lead battery 28 from the lithium ion battery 27, the lithium ion battery 27 can be used without complicating the circuit structure or switch control of the vehicle control device 10. It is possible to positively charge and discharge. As a result, the cost of the vehicle control device 10 that improves the energy efficiency of the vehicle 11 can be reduced.

As shown in FIG. 6, when the motor generator 16 is generated, the lithium ion battery 27 can be positively charged while suppressing the charging of the lead battery 28. That is, since the internal resistance of the lithium ion battery 27 is smaller than the internal resistance of the lead battery 28, it is possible to positively charge the lithium ion battery 27 while suppressing the charging of the lead battery 28. Further, as shown in FIG. 7, when the power generation of the motor generator 16 is stopped, the lithium ion battery 27 can be positively discharged while suppressing the discharge of the lead battery 28. That is, since the terminal voltage V1 of the lithium ion battery 27 is higher than the terminal voltage V2 of the lead battery 28, it is possible to positively discharge the lithium ion battery 27 while suppressing the discharge of the lead battery 28. .. In this way, since the charging / discharging of the lead battery 28 can be suppressed, the output characteristics and cycle characteristics required for the lead battery 28 can be relaxed, and the cost of the lead battery 28 can be reduced. From this point as well, the cost of the vehicle control device 10 can be reduced.

In the above description, the motor generator 16 is controlled to the power generation hibernation state when the power generation voltage VG is lowered below the terminal voltage V1, but the present invention is not limited to this. It is possible to discharge the lithium ion battery 27 even when the generated voltage VG is lower than the terminal voltage V1 while maintaining the power generation state of the motor generator 16. At this time, it is possible to control the discharge current of the lithium ion battery 27 by adjusting the generated current of the motor generator 16. That is, the discharge current of the lithium ion battery 27 can be reduced by increasing the generated current of the motor generator 16. On the other hand, the discharge current of the lithium ion battery 27 can be increased by reducing the generated current of the motor generator 16.

[Engine start control] Next, the power supply status of the vehicle control device 10 at the time of starting the engine will be described. 8 and 9 are explanatory views showing the power supply status of the vehicle control device 10. FIG. 8 shows the power supply status when the engine is first started by operating the start switch, and FIG. 9 shows the power supply status when the engine is restarted by idling stop control.

As shown in FIG. 8, when the engine is first started by the driver's start switch operation, the engine 12 is started by the starter motor 21 constituting the second starting system 62. The second starting system 62 is composed of a starter motor 21 and a lead battery 28 electrically connected to the starter motor 21. That is, when the engine is first started by operating the start switch, the starter relay 35 is closed after the open / close switch SW2 in the battery module 43 is closed. As a result, electric power is supplied from the lead battery 28 to the starter motor 21, and the engine 12 is started by the cranking operation of the starter motor 21. The open / close switch SW1 in the battery module 43 is closed after the engine 12 is started. In the above description, the open / close switch SW1 is opened from the viewpoint of suppressing the discharge of the lithium ion battery 27, but the present invention is not limited to this. For example, in a low temperature environment such as an extremely cold region, electric power may be supplied to the starter motor 21 from both the lead battery 28 and the lithium ion battery 27 by closing the open / close switches SW1 and SW2.

As shown in FIG. 9, when the engine is restarted by idling stop control, the engine 12 is started by the motor generator 16 constituting the first starting system 61. The first starting system 61 is composed of a motor generator 16 and a lithium ion battery 27 electrically connected to the motor generator 16. That is, when the engine is restarted by idling stop control, the target drive torque of the motor generator 16 is raised after the open / close switch SW2 in the battery module 43 is opened. As a result, electric power is supplied from the lithium ion battery 27 to the motor generator 16, and the engine 12 is started by the cranking operation of the motor generator 16. When the engine is restarted by idling stop control, the open / close switch SW2 is opened to disconnect the first power supply circuit 41 and the second power supply circuit 42, so that the instantaneous voltage of the second power supply circuit 42 with respect to the instantaneously low protection load 33 is applied. It is possible to prevent a decrease, that is, a momentary decrease. As a result, the operating state of the instantaneous low protection load 33 can be continued when the engine is restarted, so that the vehicle quality can be improved.

[Failsafe control] Subsequently, the fail-safe control executed by the vehicle control device 10 will be described. As described above, when the engine is restarted by idling stop control, electric power is supplied from the lithium ion battery 27 to the motor generator 16, and the engine 12 is started by the cranking operation of the motor generator 16. In this way, when the engine is restarted by idling stop control, the engine 12 is started by using the first starting system 61. Therefore, when an abnormality occurs in the first starting system 61, it is difficult to restart the engine 12 even if the starting conditions are satisfied.

Here, FIGS. 10 to 12 are explanatory views showing an example of occurrence of an abnormal state in the first starting system 61. First, as shown in FIG. 10, when a short circuit occurs in the power supply line 30 connecting the open / close switch SW2 and the fuse 37 while the engine is stopped by idling stop control (hereinafter, referred to as idling stop). , A large discharge current flows from the lithium ion battery 27 and the lead battery 28 to the short-circuited portion SC1. In this way, when a large current flows from the lithium ion battery 27 due to a short circuit of the power supply line 30 or the like, as shown in FIG. 11, the open / close switch SW1 is forcibly shut off and the lithium ion battery 27 is discharged. Is stopped. In this case, since the open / close switch SW1 is continuously shut off, power cannot be supplied from the lithium ion battery 27 to the motor generator 16, and the engine 12 is restarted even if the starting conditions are satisfied. Was difficult. Further, as shown in FIG. 12, when the ISG relay 36 is cut off due to a failure or the like, the power supply of the motor generator 16, that is, the ISG controller 24 is cut off. In this case, the motor generator 16 could not be controlled, and it was difficult to restart the engine 12 even if the starting conditions were satisfied.

Note that FIG. 11 shows the unusable state of the lithium ion battery 27, and FIG. 12 shows the undriveable state of the motor generator 16, but the abnormalities of the first starting system 61 are shown in FIGS. 11 and 12. It is not limited to examples. For example, the unusable state of the lithium-ion battery 27 is an abnormality of communication between various controllers, a shutoff of the open / close switch SW1 due to a temperature rise of the lithium-ion battery 27, a power shutoff of the battery controller 45, a failure of the battery controller 45, etc. There is. Further, as an abnormal drive impossible state of the motor generator 16, there are a communication abnormality between various controllers, a failure of the ISG controller 24, and the like.

As described above, when the lithium-ion battery 27 becomes unusable or the motor generator 16 cannot be driven, it is difficult to restart the engine 12 even if the starting conditions are satisfied. there were. Therefore, the ISS controller 52 of the control unit 50 executes the following fail-safe control in order to restart the engine 12 when an abnormality occurs in the first starting system 61.

FIG. 13 is a flowchart showing an example of the execution procedure of the fail-safe control, and FIG. 14 is an explanatory diagram showing the engine restart status by the fail-safe control. As shown in FIG. 13, in step S10, it is determined whether or not the idling stop is in progress. If it is determined in step S10 that the idling stop is in progress, the process proceeds to step S11, and it is determined whether or not the lithium ion battery 27 is in an unusable state. If it is determined in step S11 that the lithium ion battery 27 is in an unusable state, since an abnormality has occurred in the first starting system 61, the process proceeds to step S12 and the open / close switch SW1 is switched to the cutoff state. A cutoff signal is output, and the open / close switch SW1 is switched to the cutoff state (off state). In this way, after the cutoff signal for the open / close switch SW1 is output, the process proceeds to step S13, and the engine 12 is restarted by the starter motor 21.

On the other hand, if it is determined in step S11 that the lithium ion battery 27 is normal, the process proceeds to step S14, and it is determined whether or not the motor generator 16 is in an undriveable state. If it is determined in step S14 that the motor generator 16 cannot be driven, since an abnormality has occurred in the first starting system 61, the process proceeds to step S12 to switch the open / close switch SW1 to the cutoff state. A signal is output and the open / close switch SW1 is switched to the cutoff state (off state). In this way, after the cutoff signal for the open / close switch SW1 is output, the process proceeds to step S13, and the engine 12 is restarted by the starter motor 21.

As described above, when the engine 12 is restarted in step S13, as shown in FIG. 14, the ISS controller 52 that has detected the abnormality of the first starting system 61 outputs a connection signal to the starter relay 35. , The starter relay 35 is switched to the connected state (on state). As a result, power is supplied from the lead battery 28 to the starter motor 21, and the engine 12 is restarted by the cranking operation of the starter motor 21. Then, when the engine 12 is restarted, the process proceeds to step S15, and the idling stop control of the engine 12 is prohibited. That is, since an abnormality has occurred in the first starting system 61, it is prohibited to automatically stop the engine 12 based on the stop condition, and the restarted engine 12 continues the operating state. Then, in step S16, the warning light 58 is turned on in order to notify the occupant of the abnormality of the first starting system 61 and the prohibition of idling stop control.

As described above, if an abnormality occurs in the first starting system 61 during idling stop, the engine 12 is restarted using the starter motor 21, that is, the second starting system 62. As a result, even if an abnormality occurs in the first starting system 61, the engine 12 can be reliably restarted, and the running performance of the vehicle 11 can be ensured. Further, when an abnormality occurs in the first starting system 61, the engine 12 is immediately restarted by using the second starting system 62 before the starting condition in the idling stop control is satisfied. As a result, it is possible to quickly escape from the inoperable state due to the abnormality of the first starting system 61, so that the certainty of the fail-safe control can be improved.

Further, after restarting the engine 12 using the second starting system 62, idling stop control is prohibited. By prohibiting the engine stop by the idling stop control in this way, it is possible to eliminate uncertain factors that affect the vehicle running, so that various controls related to the vehicle running can be stabilized. Further, when an abnormality occurs in the first starting system 61, a cutoff signal is output to the open / close switch SW1 before the engine 12 is restarted. As a result, the power supply from the lithium ion 31 to the first starting system 61 can be cut off, and the engine 12 can be safely restarted.

It goes without saying that the present invention is not limited to the above-described embodiment and can be variously modified without departing from the gist thereof. In the above description, the ISS controller 52 functions as an engine control unit, but the present invention is not limited to this, and another controller may function as an engine control unit. Further, the engine control unit may be configured by a plurality of controllers without forming the engine control unit by one controller. In the above description, when the open / close switches SW1 and SW2 are open / closed, control signals such as a connection signal and a cutoff signal are output from the control unit 50, but the present invention is not limited to this. For example, when controlling the opening / closing of the open / close switches SW1 and SW2, a control signal may be output from the battery controller 45, or a control signal may be output from another controller.

In the above description, the lithium ion battery 27 is adopted as the first storage body and the lead battery 28 is adopted as the second storage body, but the present invention is not limited to this, and the first storage body and the second storage body are used. Any storage body may be adopted. For example, a lead battery, a nickel hydrogen battery, an electric double layer capacitor, or the like may be adopted as the first storage body. Further, as the second storage body, a lithium ion battery, a nickel hydrogen battery, an electric double layer capacitor or the like may be adopted. Further, it goes without saying that the same type of storage body may be adopted as the first storage body and the second storage body. When the lithium ion battery 27 and the lead battery 28 are combined, it is desirable to use an iron phosphate lithium ion battery in which lithium iron phosphate is applied as a positive electrode material as the lithium ion battery 27.

In the above description, the open / close switch SW2 is provided in the second power supply line 30 constituting the energization path 100, but the present invention is not limited to this, and the open / close switch SW2 is provided in the energization line 39 constituting the energization path 101. It may be provided. In this way, even when the open / close switch SW2 is provided in the energization path 101, the connection state of the lead battery 28 to the power supply circuit can be controlled. Further, the open / close switches SW1 and SW2 may be electromagnetic switches in which the contacts are operated by electromagnetic force, or semiconductor switches configured by using semiconductor elements.

In the above description, when the motor generator 16 is controlled to the combustion power generation state, the power generation voltage VG is raised to the predetermined voltage Va, and when the motor generator 16 is controlled to the regenerative power generation state, the power generation voltage VG is set to the predetermined voltage Vb. However, it is not limited to this. For example, the target power generation voltage of the motor generator 16 may be matched between the combustion power generation state and the regenerative power generation state. Further, in the combustion power generation state or the regenerative power generation state, the target power generation voltage of the motor generator 16 may be changed based on the vehicle speed, the accelerator operation amount, and the brake operation amount. Further, in the above description, the motor generator 16 that functions as a generator and an electric motor is used, but the present invention is not limited to this, and a generator that does not function as an electric motor may be used. The motor generator 16 is not limited to the induction generator, and other types of generators may be adopted.

In the above description, the motor generator 16 is driven as an electric motor when the engine is restarted by idling stop control, but the present invention is not limited to this. For example, the load on the engine 12 may be reduced by driving the motor generator 16 as an electric motor during acceleration running after the engine is started. Further, in the above description, the vehicle body load 34 is connected to the first power supply circuit 41, but the present invention is not limited to this, and the vehicle body load 34 may be connected only to the second power supply circuit 42. The vehicle body load 34 may be connected to both the power supply circuit 41 and the second power supply circuit 42.

10 Vehicle control device 11 Vehicle 12 engine 16 Motor generator (1st motor) 21 Starter motor (second motor) 27 Lithium-ion battery (1st storage body) 27a Positive electrode terminal 27b Negative electrode terminal 28 Lead battery (second storage body) 28a Positive electrode terminal 28b Negative electrode terminal 52 ISS controller (engine control unit) 61 1st starting system 62 2nd starting system 100 energization path 101 Energization path SW1 open / close switch (switch)