12-pulse thyristor control transformer type static reactive power compensation device

Abstract

The invention provides a 12-pulse thyristor control transformer type static reactive power compensation device, and relates to the technical field of reactive power compensation equipment. The system comprises a main transformer, the high-voltage side of the main transformer is connected with a high-voltage side bus through a main transformer high-voltage side switch, and the low-voltage side of the main transformer is connected with a low-voltage side bus through a main transformer low-voltage side switch; the thyristor control transformer circuit and the FC compensation circuit are respectively connected to the low-voltage side bus through a switch QF2 and a switch QF3; the control module comprises a processing unit, the processing unit is connected with a synchronous phase-shifting trigger pulse generation circuit, the synchronous phase-shifting trigger pulse generation circuit receives the low-voltage side bus voltage acquired by the acquisition module, and the output of the synchronous phase-shifting trigger pulse generation circuit is connected with a pulse amplification shaping circuit. The pulse amplifying and shaping circuit is connected with the thyristor control unit; and the processing unit is connected with the acquisition module.

Description

Technical Field

[0001] The present invention relates to the technical field of reactive power compensation equipment, and in particular to a 12-pulse thyristor controlled transformer type static reactive power compensation device. Background Art

[0002] Reactive power compensation equipment plays an extremely important role in increasing power supply capacity, improving system voltage and reducing active power loss in power systems. In power systems, especially the reactive power on the load side changes with the change of operating conditions, which means that reactive power compensation equipment should automatically track and compensate in real time according to the changing reactive power demand. Otherwise, over-compensation or under-compensation will occur, and the reactive power compensation will not be able to achieve its due effect. If the response characteristics of the automatic tracking compensation are poor, reactive power oscillation will occur, which will seriously threaten the safe operation of the power grid.

[0003] The thyristor-controlled transformer-type static reactive compensation device concentrates the advantages of various other types of SVCs. It should be able to become the leader of SVCs. However, when the demand for inductive reactive compensation is large, the large-capacity thyristor-controlled transformer-type static reactive compensation device will produce large 5th and 7th harmonic currents while adjusting the output inductive reactive compensation, which will cause the problem of large total harmonic voltage distortion rate of the access voltage level. It is precisely because the harmonic current content injected into the system by the thyristor-controlled transformer-type static reactive compensation device is too high that it is difficult to use in general occasions, which seriously restricts the widespread application and promotion of the thyristor-controlled transformer-type static reactive compensation device. Therefore, the thyristor-controlled transformer-type static reactive compensation device needs to significantly reduce the harmonic current content injected into the system without excessively increasing the manufacturing cost. Summary of the invention

[0004] In order to solve the above technical problem or at least partially solve the above technical problem, the present invention provides a 12-pulse thyristor controlled transformer type static reactive power compensation device.

[0005] In a first aspect, the present invention provides a 12-pulse thyristor controlled transformer type static reactive power compensation device, comprising: a main transformer, wherein the high voltage side of the main transformer is connected to the high voltage side bus through the main transformer high voltage side switch, and the low voltage side of the main transformer is connected to the low voltage side bus through the main transformer low voltage side switch;

[0006] A thyristor-controlled transformer circuit and an FC compensation circuit connected to the low-voltage side busbar via a switch QF2 and a switch QF3 respectively;

[0007] A control module, wherein the control module comprises a processing unit, wherein the processing unit is connected to a synchronous phase-shift trigger pulse generating circuit, wherein the synchronous phase-shift trigger pulse generating circuit receives the low-voltage side bus voltage acquired by the acquisition module, wherein the output of the synchronous phase-shift trigger pulse generating circuit is connected to a pulse amplifying and shaping circuit, wherein the pulse amplifying and shaping circuit is connected to the thyristor control unit; wherein the processing unit is connected to the acquisition module to acquire the low-voltage side bus voltage, the low-voltage side bus current, the FC compensation circuit current and the thyristor control transformer circuit current;

[0008] The processing unit outputs a given driving signal to a given input port of a synchronous phase-shift trigger pulse generating circuit. The synchronous phase-shift trigger pulse generating circuit receives a voltage synchronization signal of a low-voltage side bus. The 12-pulse synchronous phase-shift trigger pulse generated by the synchronous phase-shift trigger pulse generating circuit is output to a pulse amplifying and shaping circuit. The pulse output by the pulse amplifying and shaping circuit controls two reverse-parallel thyristors of each phase line to conduct at a synchronous trigger delay angle α, so that the thyristor-controlled transformer circuit outputs an inductive current corresponding to the trigger delay angle α.

[0009] Furthermore, each thyristor control unit includes two thyristors connected in reverse parallel, and the driving pins of the thyristors are connected to the pulse amplification and shaping circuit of the control module.

[0010] Furthermore, the FC compensation circuit includes a reactor, a filter capacitor connected to the reactor, and the three-phase filter capacitor is star-connected.

[0011] Furthermore, the acquisition module includes: a thyristor-controlled transformer circuit current transformer connected to each thyristor-controlled transformer circuit; an FC compensation circuit current transformer connected to each FC compensation circuit; a low-voltage bus voltage transformer connected to the low-voltage side bus of the main transformer for measuring the low-voltage side bus voltage of the main transformer; and a low-voltage bus current transformer connected to the low-voltage side bus of the main transformer for measuring the low-voltage side bus current of the main transformer.

[0012] Furthermore, the thyristor-controlled transformer circuit includes: a 15° forward phase-shifting transformer T1 and a 15° reverse phase-shifting transformer T2 connected in parallel; the primary sides of the 15° forward phase-shifting transformer T1 and the 15° reverse phase-shifting transformer T2 are connected to the low-voltage side bus of the main transformer; each phase line of the secondary side of the 15° forward phase-shifting transformer T1 is connected to the inductor L1, and each phase line of the secondary side of the reverse 15° phase-shifting transformer T2 is connected to the inductor L2; the inductor L1 and the inductor L2 on each phase line are respectively connected to the thyristor control unit, and the three-phase thyristor control unit is star-connected.

[0013] Furthermore, the synchronous phase-shift trigger pulse generating circuit includes at least one Schmitt trigger, which uses the driving signal and the voltage synchronization signal of the low-voltage side bus as trigger input signals, and the output of the Schmitt trigger is connected to the pulse amplification and shaping circuit.

[0014] Furthermore, the pulse amplification and shaping circuit includes: a coupling resistor coupled to the output end of the synchronous phase-shift trigger pulse generating circuit, the coupling resistor is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to the primary side of the pulse transformer, the primary side of the pulse transformer is connected to the 24V power supply via a pull-up resistor, the secondary side of the pulse transformer is connected to a pulse shaping circuit formed by two rectifier diodes, and the pulse shaping circuit is connected to a thyristor.

[0015] Furthermore, the control module controls at least the switch QF3 through the driving circuit, and when the thyristor-controlled transformer circuit is used as a controllable high-voltage reactor, the FC compensation circuit is not connected.

[0016] Furthermore, the liquid immersion heat dissipation design of the thyristor controlled transformer circuit includes the following methods:

[0017] The forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are installed in the heat dissipation oil tank respectively;

[0018] The forward 15° phase-shifting transformer T1 and the reactor L1, and the reverse 15° phase-shifting transformer T2 and the reactor L2 are respectively combined and installed in the heat dissipation oil tank to form two split-type thyristor-controlled transformer circuits with phase shifts of +15° and -15° respectively;

[0019] The forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are combined and installed in a heat dissipation oil tank to form an integral structure.

[0020] Furthermore, the dry heat dissipation design of the thyristor controlled transformer circuit is as follows: the forward 15° phase-shifting transformer T1 and the reverse 15° phase-shifting transformer T2 are respectively arranged in the dry heat dissipation transformer housing, and the reactor L1 and the reactor L2 are respectively arranged in the dry heat dissipation reactor housing.

[0021] The above technical solution provided by the embodiment of the present invention has the following advantages compared with the prior art:

[0022] The thyristor controlled transformer circuit of the present application is responsible for smoothly adjusting the inductive reactive output to offset the fixed capacitive reactive output of the FC compensation circuit, so that the real-time reactive output of the reactive compensation is balanced with the real-time reactive load of the power system, thereby achieving the working goal of real-time automatic tracking and compensation of the rapidly changing reactive load. The thyristor controlled transformer circuit can also be used as a controllable high-voltage reactor alone to compensate for the capacitive reactive power of the power system transmission line and stabilize the line voltage.

[0023] Compared with the thyristor-controlled reactor-type static reactive power compensation device, the 12-pulse thyristor-controlled transformer-type static reactive power compensation device has a greater advantage in terms of operational reliability. The thyristors of the thyristor-controlled transformer circuit are located on the low-voltage side of the high-impedance transformer, with a lower operating voltage. There is no need to use the thyristors in series, and there are no problems with the series voltage balancing and trigger conduction consistency of the thyristors under high voltage levels. The operational reliability of the thyristor valve group is much higher than that of the thyristor-controlled reactor-type static reactive power compensation device. And working on the low-voltage side can ensure that the thyristor-controlled transformer circuit has a longer life and is more convenient for maintenance and management.

[0024] Compared with the magnetically controlled reactor type static reactive power compensation device, the 12-pulse thyristor-controlled transformer type static reactive power compensation device has a greater advantage in response time characteristics. The inductive reactive power of the thyristor-controlled transformer circuit is coupled from the low-voltage side to the high-voltage side, which is a direct electrical coupling. There is no need to change the transformer core flux, and there is no influence of the hysteresis of the core material on the response time. The response time can be within 20ms. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0026] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0027] Figure 1 A flow chart of a 12-pulse thyristor controlled transformer type static reactive power compensation device provided by an embodiment of the present invention;

[0028] Figure 2 A schematic diagram of a fully split thyristor controlled transformer circuit provided by an embodiment of the present invention;

[0029] Figure 3A schematic diagram of a split thyristor controlled transformer circuit provided by an embodiment of the present invention;

[0030] Figure 4 A schematic diagram of an integrated thyristor controlled transformer circuit provided by an embodiment of the present invention;

[0031] Figure 5 A schematic diagram of a synchronous phase-shift trigger pulse generating circuit and a pulse amplifying and shaping circuit provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] It should be noted that, in this article, the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0034] Example 1

[0035] like Figure 1 As shown, the present invention realizes a 12-pulse thyristor controlled transformer type static reactive power compensation device to meet the requirements of dynamic reactive power compensation accuracy and response time of the power system.

[0036] The present invention comprises:

[0037] Main transformer, the high voltage side of the main transformer is connected to the high voltage side busbar through the main transformer high voltage side switch, and the low voltage side of the main transformer is connected to the low voltage side busbar through the main transformer low voltage side switch. Figure 1 As shown, Figure 1 The high voltage side of the main transformer is connected to the high voltage side bus through the main transformer high voltage side switch QS1, and the low voltage side of the main transformer is connected to the low voltage I section bus through the main transformer low voltage side switch QF1.

[0038] The thyristor-controlled transformer circuit and the FC compensation circuit are connected to the low-voltage side bus through the switch QF2 and the switch QF3 respectively; Figure 1As shown, the thyristor-controlled transformer circuit is connected to the low-voltage side I-section bus through the switch QF2.

[0039] The thyristor-controlled transformer circuit includes: a 15° forward phase-shifting transformer T1 and a 15° reverse phase-shifting transformer T2 connected in parallel; the primary sides of the 15° forward phase-shifting transformer T1 and the 15° reverse phase-shifting transformer T2 are connected to the low-voltage bus of the main transformer; each phase line of the secondary side of the 15° forward phase-shifting transformer T1 is connected to the reactor L1, and each phase line of the secondary side of the reverse phase-shifting transformer T2 is connected to the reactor L2. The inductor L1 and the inductor L2 on each phase line are connected to the thyristor control unit, each thyristor control unit includes two thyristors connected in reverse parallel, the driving pins of the thyristors are connected to the control module, and the three-phase thyristors are star-connected.

[0040] like Figure 2 , Figure 3 and Figure 4 As shown, in a three-phase line, the thyristor controlled transformer circuit includes the primary side of the phase-shifting transformer T1 extending by 15° connected as a +15° extended triangle, the three-phase reactor L1 is respectively connected in series to the star-connected terminals a1, b1, c1 of the low-voltage side of the phase-shifting transformer T1 extending by 15°, and the three-phase reactor L1 is further connected to the U1, V1, W1 terminals of the thyristor valve group 1VT, the thyristor valve group 1VT includes a thyristor control unit formed by 3 groups of reverse parallel thyristors, the thyristor control unit is connected in a star shape, and the end of the reactor L1 is connected in a star shape to form a 6-pulse thyristor phase-shifting inductance modulation circuit extending by 15°. The primary side of the reverse-extended 15° phase-shifting transformer T2 is connected in a -15° extended triangle, and the three-phase reactor L2 is respectively connected in series to the star-connected terminals a2, b2, and c2 of the low-voltage side of the reverse-extended 15° phase-shifting transformer T2. The three-phase reactor L2 is then connected to the U2, V2, and W2 terminals of the thyristor valve group 2VT. The thyristor valve group 2VT includes a thyristor control unit formed by three groups of reverse-parallel thyristors. The thyristor control unit is connected in a star shape, and the ends of the three-phase reactor L2 are connected in a star shape to form a 6-pulse thyristor phase-shifting inductance modulation circuit with a reverse extension of 15°. Due to the 30° phase difference between the two 6-pulse thyristor phase-shifting inductance modulation circuits, a 12-pulse thyristor phase-shifting inductance modulation circuit is formed.

[0041] The FC compensation circuit includes a reactor, a filter capacitor connected to the reactor, and the three-phase filter capacitors are star-connected. Figure 1 As shown, the FC compensation circuit connected to the low-voltage side I-section bus includes a reactor L3, a filter capacitor C1 connected to the reactor L3, and the three-phase filter capacitor C1 is star-connected.

[0042] The acquisition module includes: a thyristor-controlled transformer circuit current transformer connected to each thyristor-controlled transformer circuit; an FC compensation circuit current transformer connected to each FC compensation circuit; a low-voltage bus voltage transformer connected to the low-voltage side bus of the main transformer for measuring the voltage of the low-voltage side bus of the main transformer; and a low-voltage bus current transformer connected to the low-voltage side bus of the main transformer for measuring the current of the low-voltage side bus of the main transformer. Figure 1 In the example, a low-voltage bus voltage transformer TV1 is set on the low-voltage side section I bus, a low-voltage bus current transformer TA1 is set upstream of the low-voltage side section I bus switch QF1, a thyristor-controlled transformer circuit current transformer TA2 is set at the thyristor-controlled transformer circuit connected to the low-voltage side section I bus, and an FC compensation circuit current transformer TA3 is set at the FC compensation circuit connected to the low-voltage side section I bus.

[0043] Control module; the control module comprises a processing unit, a synchronous phase-shift trigger pulse generating circuit, and a pulse amplifying and shaping circuit, and the pulse amplifying and shaping circuit is connected to the thyristor control unit.

[0044] During the implementation, the processing unit is realized by a single-chip microcomputer, and the pin of the single-chip microcomputer supporting RS485 communication is connected to a host computer through an RS485 communication link.

[0045] The processing unit is connected to each low-voltage bus voltage transformer, low-voltage bus current transformer, FC compensation circuit current transformer and thyristor-controlled transformer circuit current transformer. To obtain the low-voltage side bus voltage, low-voltage side bus current, FC compensation circuit current and thyristor-controlled transformer circuit current. The processing unit collects the states of the main transformer high-voltage side switch QS1, the main transformer low-voltage side switch QF1, switch QF2 and switch QF3. The processing unit controls at least switch QF3 through a driving circuit. In this application, when the thyristor-controlled transformer circuit is used as a controllable high-voltage reactor, the FC compensation circuit is not connected.

[0046] The processing unit is connected to the synchronous phase-shift trigger pulse generating circuit, and the processing unit outputs a given driving signal to a given input port of the synchronous phase-shift trigger pulse generating circuit. The synchronous phase-shift trigger pulse generating circuit receives the voltage synchronization signal of the low-voltage side bus, and the 12-pulse synchronous phase-shift trigger pulse generated by the synchronous phase-shift trigger pulse generating circuit is output to the pulse amplification and shaping circuit, and the pulse amplification and shaping circuit is connected to the driving pins of the reverse parallel thyristors of each phase line. The two reverse parallel thyristors of each phase line are turned on according to the synchronous trigger delay angle α, so that the thyristor control transformer circuit outputs an inductive current corresponding to the trigger delay angle α.

[0047] During the specific implementation process, the synchronous phase-shift trigger pulse generation circuit includes at least one Schmitt trigger. The Schmitt trigger uses the drive signal and the voltage synchronization signal of the low-voltage side bus as trigger input signals, and the output of the Schmitt trigger is connected to two pulse amplification and shaping circuits. The pulse amplification and shaping circuit includes: a coupling resistor coupled to the output end of the Schmitt trigger, the coupling circuit is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to the primary side of the pulse transformer, and the primary side of the pulse transformer is connected to a 24V power supply via a pull-up resistor. The secondary side of the pulse transformer is connected to a pulse shaping circuit formed by two rectifier diodes, and the pulse shaping circuit is electrically connected to the thyristor. Figure 5 As shown, a pulse amplification and shaping circuit includes: a coupling resistor R103 coupled to the output end of the Schmitt trigger, the coupling resistor R103 is connected to the base of the transistor Q101, the emitter of the transistor Q101 is grounded, the collector of the transistor Q101 is connected to the primary side of the pulse transformer T101, and the primary side of the pulse transformer T101 is connected to the 24V power supply via the pull-up resistor R101. The primary side of the pulse transformer T101 is connected in parallel with a protection resistor R102 and a clamping diode D101. When the transistor Q101 is disconnected, the protection resistor R102 and the clamping diode D101 continue to eliminate the reverse voltage of the primary side of the pulse transformer, and the protection resistor R102 is used to limit the follow-through current. Another pulse amplification and shaping circuit includes: a coupling resistor R203 coupled to the output end of the Schmitt trigger, the coupling resistor R203 is connected to the base of the transistor Q201, the emitter of the transistor Q201 is grounded, the collector of the transistor Q201 is connected to the primary side of the pulse transformer T201, and the primary side of the pulse transformer T201 is connected to the 24V power supply via the pull-up resistor R201. The primary side of the pulse transformer T201 is connected in parallel with a protection resistor R202 and a clamping diode D201. When the transistor Q201 is disconnected, the protection resistor R202 and the clamping diode D201 will continue to eliminate the reverse voltage of the primary side of the pulse transformer, and the protection resistor R202 is used to limit the follow-through current.

[0048] Example 2

[0049] In this application, the thyristor-controlled transformer circuit is the main source of heat, and its design needs to meet the heat dissipation requirements. In the power system, the heat dissipation of the device includes dry type and liquid immersion type. The dry heat dissipation design of the thyristor-controlled transformer circuit is as follows: Figure 2 As shown, the forward 15° phase-shifting transformer T1 and the reverse 15° phase-shifting transformer T2 are respectively arranged in a dry heat dissipation transformer housing, and the reactor L1 and the reactor L2 are respectively arranged in a dry heat dissipation reactor housing. It is suitable for small-capacity scenarios with oil-free requirements.

[0050] The liquid immersion heat dissipation design of the thyristor controlled transformer circuit can be designed as Figure 2The fully split thyristor controlled transformer circuit of independent devices shown in the figure, the forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are installed in the heat sink respectively, which is suitable for large-capacity scenarios; it can also be as Figure 3 As shown, the forward 15° phase-shifting transformer T1 and the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are respectively combined and installed in the heat dissipation oil tank to form two split-type thyristor-controlled transformer circuits with phase shifts of +15° and -15° respectively, which are suitable for larger capacity scenarios; the forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 can also be combined and installed in a heat dissipation oil tank to form an integrated structure, which is suitable for medium capacity scenarios.

[0051] In the embodiments provided by the present invention, it should be understood that the disclosed structure can be implemented in other ways. For example, the structural embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, structures or units, which can be electrical, mechanical or other forms.

[0052] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0053] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0054] The foregoing is merely a specific embodiment of the present invention, which enables those skilled in the art to understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A 12-pulse thyristor controlled transformer type static reactive power compensation device, characterized in that: include: Main transformer, the high voltage side of the main transformer is connected to the high voltage side busbar through the main transformer high voltage side switch, and the low voltage side of the main transformer is connected to the low voltage side busbar through the main transformer low voltage side switch; A thyristor-controlled transformer circuit and an FC compensation circuit connected to the low-voltage side busbar via a switch QF2 and a switch QF3 respectively; A control module, wherein the control module comprises a processing unit, wherein the processing unit is connected to a synchronous phase-shift trigger pulse generating circuit, wherein the synchronous phase-shift trigger pulse generating circuit receives the low-voltage side bus voltage acquired by the acquisition module, wherein the output of the synchronous phase-shift trigger pulse generating circuit is connected to a pulse amplifying and shaping circuit, wherein the pulse amplifying and shaping circuit is connected to the thyristor control unit; wherein the processing unit is connected to the acquisition module to acquire the low-voltage side bus voltage, the low-voltage side bus current, the FC compensation circuit current and the thyristor control transformer circuit current; The processing unit outputs a given driving signal to a given input port of a synchronous phase-shift trigger pulse generating circuit. The synchronous phase-shift trigger pulse generating circuit receives a voltage synchronization signal of a low-voltage side bus. The 12-pulse synchronous phase-shift trigger pulse generated by the synchronous phase-shift trigger pulse generating circuit is output to a pulse amplifying and shaping circuit. The pulse output by the pulse amplifying and shaping circuit controls two reverse-parallel thyristors of each phase line to conduct at a synchronous trigger delay angle α, so that the thyristor-controlled transformer circuit outputs an inductive current corresponding to the trigger delay angle α.

2. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: Each thyristor control unit includes two thyristors connected in reverse parallel, and the driving pins of the thyristors are connected to the pulse amplification and shaping circuit of the control module.

3. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The FC compensation circuit includes a reactor and a filter capacitor connected to the reactor, and the three-phase filter capacitors are star-connected.

4. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The acquisition module includes: a thyristor-controlled transformer circuit current transformer connected to each thyristor-controlled transformer circuit; an FC compensation circuit current transformer connected to each FC compensation circuit; a low-voltage bus voltage transformer connected to the low-voltage side bus of the main transformer for measuring the bus voltage on the low-voltage side of the main transformer; and a low-voltage bus current transformer connected to the low-voltage side bus of the main transformer for measuring the bus current on the low-voltage side of the main transformer.

5. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The thyristor controlled transformer circuit comprises: a 15° forward phase-shifting transformer T1 and a 15° reverse phase-shifting transformer T2 connected in parallel; the primary sides of the 15° forward phase-shifting transformer T1 and the 15° reverse phase-shifting transformer T2 are connected to the low-voltage side bus of the main transformer; each phase line of the secondary side of the 15° forward phase-shifting transformer T1 is respectively connected to the reactor L1, and each phase line of the secondary side of the reverse 15° phase-shifting transformer T2 is respectively connected to the reactor L2; the inductor L1 and the inductor L2 on each phase line are respectively connected to the thyristor control unit, and the three-phase thyristor control units are star-connected.

6. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The synchronous phase-shift trigger pulse generating circuit comprises at least one Schmitt trigger, which uses a driving signal and a voltage synchronization signal of a low-voltage side bus as trigger input signals, and the output of the Schmitt trigger is connected to a pulse amplification and shaping circuit.

7. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The pulse amplification and shaping circuit includes: a coupling resistor coupled to the output end of the synchronous phase-shift trigger pulse generating circuit, the coupling resistor is connected to the base of the transistor, the emitter of the transistor is grounded, the collector of the transistor is connected to the primary side of the pulse transformer, the primary side of the pulse transformer is connected to the 24V power supply via a pull-up resistor, the secondary side of the pulse transformer is connected to a pulse shaping circuit formed by two rectifier diodes, and the pulse shaping circuit is connected to a thyristor.

8. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The control module controls at least the switch QF3 through the driving circuit. When the thyristor-controlled transformer circuit is used as a controllable high-voltage reactor, the FC compensation circuit is not connected.

9. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The liquid immersion heat dissipation design of thyristor controlled transformer circuit includes the following methods: The forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are installed in the heat dissipation oil tank respectively; The forward 15° phase-shifting transformer T1 and the reactor L1, and the reverse 15° phase-shifting transformer T2 and the reactor L2 are respectively combined and installed in the heat dissipation oil tank to form two split-type thyristor-controlled transformer circuits with phase shifts of +15° and -15° respectively; The forward 15° phase-shifting transformer T1, the reactor L1, the reverse 15° phase-shifting transformer T2 and the reactor L2 are combined and installed in a heat dissipation oil tank to form an integral structure.

10. The 12-pulse thyristor controlled transformer type static reactive power compensation device according to claim 1, characterized in that: The dry heat dissipation design of the thyristor controlled transformer circuit is as follows: the forward 15° phase-shifting transformer T1 and the reverse 15° phase-shifting transformer T2 are respectively arranged in the dry heat dissipation transformer housing, and the reactor L1 and the reactor L2 are respectively arranged in the dry heat dissipation reactor housing.

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