Three-phase transformer phase regulator

The invention relates to electric power, and can be used to direct the flows of active power in the branches of electric transmission and distribution relays.

It is known the phase regulator with transformer, which includes two three-phase transformers, one of which performs the function of the excitation element (the parallel), and the other - the function of the phase element (consecutive). At the same time, the supply voltage of the low voltage windings of the phase shift transformer is changed by the stepwise switching of the branches of the low voltage regulating coils of the excitation element using the grounded contacts of the load switch mechanism [1].

The disadvantages of this regulator consist in the complexity and the massiveness of the construction, caused by the need to use and coordinate the operation of two transformer elements, as well as the problems related to the transport and choice of the place of installation and assembly of the regulator at the transformation station. At the same time, the typical power of the installation increases significantly as the maximum angle of phase shift increases, for which the machine is calculated according to the operating conditions in the corresponding nodes of the electrical network. The advantage of this technical solution consists in the possibility of installing the switch of the adjusting branches in the neutral wire of the connection scheme of the adjusting springs, that is, without the need for the special isolation protection of the housing, as well as other elements of this switch from the dangerous voltages in the network.

Also known is the three-phase phase regulator with transformer, made on the basis of a single transformer, the mass and dimensions of which are more favorable.

The disadvantage of this phase regulator is the need to use a special insulation platform for operating at Maltese voltages to install the switching mechanism under load. The cost and dimensions of this platform increase sharply as the voltage class of the electric transmission lines increases for which the given regulator is expected. Starting from a certain voltage level, such a regulator, made on the basis of a single transformer, loses its advantages compared to the phase regulator made on the basis of two transformers.

The problem solved by the proposed invention is the creation of a three-phase phase regulator with a single transformer, guided with the help of ground-based switching contacts of the switching mechanism of the adjusting branches under load, which will ensure the use of a compact, comfortable construction at transport, installation and servicing of the installation, with parameters close to those of the devices made on the basis of two transformers.

The controller, according to the invention, removes the disadvantages mentioned above in that it confines a magnetic circuit with three cores, on each core of which are placed a number of primary and secondary windings with the same number of turns, as well as о adjustable winding with sockets. intermediaries, a mechanism for switching under load with earth-connected mobile contacts, a three-phase switch doubled with two positions a and b to change the direction of adjustment of the phase shift angle. The ends of the primary windings are connected to the ends of the secondary windings and to the beginning of the adjustment windings by means of a three-phase double switch with two positions for changing the direction of adjustment of the phase shift angle.

All the exposed characteristics ensure the possibility of solving the problem with the help of a single transformer guided by a mechanism of switching under load with the mobile contacts connected to the ground.

The invention is explained by the drawings in FIG. 1 and 2, representing:

FIG. 1, the main electrical diagram of the phase regulator, in which:

Al, Bl and Cl - the electrical inputs (input pumps) of the phase regulator;

A2, B2 and C2 - the electrical outputs (output terminals) of the phase regulator;

А, В, C - the name of the respective phases of the three-phase system;

- the primary winding of phase A;

- the primary winding of phase B;

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- the primary phase C winding;

- the secondary winding of phase A;

- secondary phase B winding;

- the secondary winding of phase C;

- phase A adjustment wrap;

- phase B adjustment wrap;

- phase C adjustment wrap;

- the mobile contact of phase A of the mechanism for switching the adjusting branches under load;

- the mobile contact of the phase В of the mechanism for switching the adjusting branches under load;

- the mobile contact of phase C of the mechanism for switching the adjusting branches under load;

- the ferromagnetic core of phase A;

- the ferromagnetic core of phase B;

- the ferromagnetic core of phase C;

- the three-phase switch doubled with two positions;

a, b - first and second positions of switch 16;

* - the symbol that marks the beginning of the corresponding winding of the transformer;

FIG. 2, the vector diagrams of the voltages of the three phase phase regulator with transformer for different positions of the switch 16:

FIG. 2a, for the position of the switch 16;

FIG. 2b, for the position of the switch 16.

The list of elements in fig. 2:

UA1, UB1 and UC1 - phase voltages at the phase regulator input; UA2, UB2 and UC2 - phase voltages from the phase regulator output;

U1A, U1B and U1C - the voltages at the primary windings 1, 2, 3 of the phase regulator;

U2A, U2B and U2C - the voltages at the secondary windings 4, 5, 6 of the phase regulator;

UPA, UPB and UPC - the voltages taken from the regulator windings 7, 8, 9 of the phase regulator;

ψ - the phase shift angle between the three-phase systems of the voltage vectors at the input and output of the phase regulator.

The three-phase phase controller with transformer (see fig. 1) confines a magnetic circuit with three cores, on each core whose primary windings 1, 2, 3 and a secondary winding 4, 5, 6 are located with the same number of turns, forming phases А, В and C. The beginnings Al, B1 and Cl of the primary windings are the electrical inputs of the phase regulator. The beginnings A2, B2 and C2 of the secondary windings are the electrical outputs of the phase regulator. The equal number of turns of the primary and secondary windings ensures the symmetry of the adjustment, which means the equality of the input and output voltage modules in the adjustment process in the absence of load current at the phase regulator output. the adjusting windings 7, 8 and 9, the number of turns of which is determined depending on the maximum phase shift given when designing the phase regulator, are located on the same cores of the magnetic circuit. The movable contacts 10, 11 and 12, coupled with the intermediate sockets of the adjusting windings, are controlled by means of the mechanical execution body of the load-switching mechanism, common for all phases, through which the full coordination of the switching operations is carried out in all phases. . The notion of "mobile contact" in this case includes both its execution in the form of sliding contact, as well as a contact, which ensures the switching of the adjustment branches in stages. The aforementioned mobile contacts are electrically bonded to each other and form the grounded neutral of the three phase phase regulator with transformer.

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The two-position three-phase double switch 16 is intended for changing the direction of adjustment of the phase shift angle in advance or phase delay. If the output voltage of the regulator is offset relative to the input voltage in the direction of the clockwise movement, then the phase shift angle is considered in advance (positive). Otherwise, the phase shift angle is delayed (negative). The position of the switch 16 corresponds to the adjustment of the phase shift angle in the region of its positive values, position b - in the region of the negative values.

In the position of the switch 16 the ends of the primary windings 1, 2 and 3 are connected to the ends of the secondary windings 5, 6 and 4 correspondingly, at the same time at the connection point of each pair of formed windings the beginning of the corresponding windings 9, 7 and 8 is connected.

In the position of the switch 16 the grooves of the primary windings 1, 2 and 3 are connected to the ends of the corresponding secondary windings 6, 4 and 5, at the same time at the connection point of each pair of formed windings the beginning of the corresponding windings 8, 9 and 7 is connected.

The three phase phase controller with transformer operates in the following mode.

When applying the network voltage to the input terminals Al, Bl and Cl, a closed electrical circuit is formed through the movable contacts 10, 11 and 12 of the magnetization current, which generates a magnetic flux in the magnetic cores, under which the action in the primary, secondary and secondary windings. the voltages determined by the number of turns of each winding are set to adjust the transformer.

The vector diagram, which explains the operating principle of the phase regulator when switch 16 is switched to position a, is shown in FIG. 2.

According to this vector diagram, the following state of the phase controller diagram is established:

- the beginning of the voltage vector U1A, which belongs to the primary phase winding

A, is joined to the beginning of the voltage vector U2B, which belongs to the secondary winding of phase B, and the common connection point of the mentioned pair of vectors is removed at the end of the adjustable voltage vector UPC belonging to the winding of phase C;

- the beginning of the voltage vector U1B, which belongs to the primary winding of phase B, is joined to the beginning of the voltage vector U2C, which belongs to the secondary winding of phase C, and the common connection point of the mentioned pair of vectors is removed at the end of the adjustable voltage vector UPA which belongs to the phase A winding;

- the beginning of the voltage vector U1C, which belongs to the primary winding of phase C, is joined to the beginning of the vector of voltage U2A, which belongs to the secondary winding of phase A, and the common connection point of the mentioned pair of vectors is removed at the end of the adjustable voltage vector UPB which belongs to the phase winding В.

The switching of the branches of the adjustment windings 7, 8 and 9 with the help of the mobile contacts 10, 11 and 12 is accompanied by the change of the voltages UPA, UPB and UPC by value, which ensures the positive sign of the phase shift angle ψ regulated between the three-phase systems of the input voltages. UA1, UB1, UC1 and output phase UA2, UB2, UC2 of the phase regulator.

The vector diagram, which explains the operating principle of the phase regulator when switch 16 is switched to position b, is shown in FIG. 2b.

According to this vector diagram, the following state of the phase controller diagram is established:

- the beginning of the voltage vector U1A, which belongs to the primary phase winding

B, is joined to the beginning of the voltage vector U2C, which belongs to the secondary winding of phase C, and the common connection point of the mentioned pair of vectors is removed at the end of the adjustable voltage vector UPB belonging to the winding of phase B;

- the beginning of the voltage vector U1B, which belongs to the primary winding of phase B, is joined to the beginning of the voltage vector U2A, which belongs to the secondary winding of phase A, and the common connection point of the mentioned pair of vectors is subtracted from the outline of the adjustable voltage vector UPC which belongs to the C phase wrap;

- the beginning of the voltage vector U1C, which belongs to the primary winding of phase C, is joined to the beginning of the vector of voltage U2B, which belongs to the secondary winding

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of phase B, and the common point of connection of said pair of vectors is removed at the end of the adjustable voltage vector UPA belonging to the winding of phase A.

Switching switch 16 to position b provides the negative sign of the phase shift angle ψ regulated between the three-phase systems of the input voltages 5 UA1, UB1, UC1 and the output UA2, UB2, UC2 of the three-phase phase regulator.

Thus, the use of the additional windings, the double-position switch, as well as the proposed connection of the primary, secondary and adjustable windings, ensures the possibility of creating a compact three-phase phase regulator with transformer with the earth-connected mobile contacts of the switching mechanism 10 below. task of the adjustment branches.

(56) Bibliographic references cited in the description:

1. Tirupathi Reddy, Aruna Gulati, Μ. I. Khan, Ramesh Koul. Application of Phase Shifting Transformer in Indian Power System. International Journal of Computer and Electrical Engineering, vol. 4, No. 2, April, found on the Internet on 2015.11.09, url: 2012h ttp: // www. ij cee.org/paper s / 487-N20041 .pdf

2. SI J Ϊ60Ϊ7Ϊ4 To 1990.10.23 .......................................

(57) Claims: