Reactive power strong compensation device and method based on IGCT (integrated gate commutated thyristor) and anti-parallel thyristors

Abstract

The invention belongs to the field of high-voltage power transmission and transformation, and discloses a reactive power strong compensation device and method based on IGCT and anti-parallel thyristors, the device comprises at least one group of reactive power strong compensation circuits, and each reactive power strong compensation circuit comprises an IGCT driving module, a thyristor, a charging voltage-sharing module and an energy-taking power supply module; the IGCT driving module and the anti-parallel thyristors work cooperatively to control the conduction and turn-off of forward current and the conduction of reverse current, so that the accuracy and timeliness of switching are ensured; meanwhile, the introduction of the charging voltage-sharing module and the energy-taking power supply module ensures the balance of series voltages at all levels in the dynamic circuit and the stable power supply of the driving module, thereby improving the performance and reliability of the whole device. By adopting the device, faster switching response can be realized, and the switching phase can be accurately controlled, so that the problem of system voltage and current overshoot caused by improper switching phase is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of high-voltage power transmission and transformation, and in particular relates to a reactive power strengthening device and method based on IGCT and anti-parallel thyristor. Background Art

[0002] With the rapid development of the power grid, the continuous improvement of power grid capacity, and the complex access of different power grid topologies, the interconnection of AC and DC power grids such as traditional energy, new energy, and intermittent energy has formed a large and complex power system network. Grid safety and power quality are of vital importance.

[0003] There are various ways to manage power quality, among which the widely used methods are: static VAR compensation device (SVC), static VAR generator SVG (STACOM), active filter (APF), passive filter, fixed capacitor bank, etc.; among them, fixed capacitor bank, as a passive device, has the characteristics of high reliability, low cost, and strong environmental adaptability; however, the switching method of traditional switch circuit breaker has slow response speed and cannot accurately control the switching phase, which easily causes improper switching phase and leads to system voltage and current overshoot.

[0004] It can be seen that the switching method of traditional switch circuit breakers has a slow response speed and cannot accurately control the switching phase, which can easily cause improper switching phase and lead to system voltage and current overshoot. Summary of the invention

[0005] The present invention provides a reactive power strengthening device and method based on IGCT and anti-parallel thyristor to solve the technical problems that the switching mode of traditional switch circuit breaker has slow response speed, cannot accurately control the switching phase, easily causes improper switching phase, and leads to system voltage and current overshoot.

[0006] In order to achieve the above object, the present invention adopts the following technical contents: A reactive power compensation device based on IGCT and anti-parallel thyristor, comprising at least one set of reactive power compensation circuits; The reactive power compensation circuit comprises: an IGCT driving module, a thyristor, a charging voltage equalization module and an energy-taking power supply module; The charging voltage balancing module is used to charge the energy extraction power supply module and to maintain the balance of the series voltages at each level in the dynamic circuit; The IGCT driving module comprises a connected IGCT and a driving module; The IGCT is used as a reference positive direction of the AC voltage to control the forward current conduction and shutdown; The thyristor is connected in reverse parallel to the two ends of the IGCT, and is used as a reference to the reverse direction of the positive direction to control the conduction of the reverse current; The energy extraction power supply module is used to supply power to the driving module.

[0007] Furthermore, the charging voltage balancing module includes a damping resistor and a damping capacitor; The damping resistor, the damping capacitor and the energy extraction power supply module are sequentially connected in series and then connected in parallel with the IGCT.

[0008] Furthermore, the anode of the IGCT is connected to the cathode of the thyristor, and the cathode of the IGCT is connected to the anode of the thyristor.

[0009] Furthermore, the reactive power strengthening device comprises a plurality of reactive power strengthening circuits, and the plurality of reactive power strengthening circuits are connected in series.

[0010] Furthermore, a plurality of groups of reactive power reinforcement circuits are electrically connected to the control and protection system respectively.

[0011] Furthermore, the reactive power compensation circuit also includes a static voltage balancing module; the static voltage balancing module is connected in series with the driving module, and is used to detect the voltage of each level of the reactive power compensation circuit, and to maintain the balance of the series voltage of each level in the static circuit.

[0012] A working method of a reactive power compensation device based on IGCT and anti-parallel thyristor, based on the above-mentioned reactive power compensation device based on IGCT and anti-parallel thyristor, comprises: The charging voltage equalization module charges the energy-taking power module and maintains the balance of the series voltages at all levels in the dynamic circuit; The energy-taking power supply module supplies power to the drive module; The driver module monitors and controls the IGCT; The IGCT is used as the reference positive direction of the AC voltage to control the on and off of the forward current; The thyristor is used as a reference to the opposite direction of the positive direction to control the conduction of the reverse current.

[0013] A monitoring method for a reactive power compensation device based on IGCT and anti-parallel thyristor is based on the above-mentioned reactive power compensation device based on IGCT and anti-parallel thyristor, comprising: When it is monitored that the AC voltage of the power system exceeds a first threshold, the IGCT feeds back a positive signal; At the next moment, according to the received first trigger conduction signal, the IGCT conducts the forward current, so that the voltage of the reactive power compensation device is reduced; At another moment, according to the received shutdown signal, the IGCT shuts off the forward current and changes the conduction state to the blocking state; When it is monitored that the AC voltage of the power system is lower than the second threshold, the IGCT feeds back a reverse signal; At the next moment, according to the received second trigger conduction signal, the thyristor conducts the reverse current, so that the voltage of the reactive power compensation device is reduced.

[0014] Furthermore, the IGCT and the thyristor are controlled by a control pulse output by a control and protection system; the control pulse includes a first trigger on signal, a second trigger on signal and a turn-off signal; wherein the pulse widths corresponding to the control pulses are different.

[0015] Furthermore, the reactive power compensation circuit is connected in series with the load and the closed switch in the loop of the secondary side of the voltage regulator; A first trigger optical fiber and a feedback optical fiber are connected between the IGCT and the control and protection system; A second trigger optical fiber is connected between the thyristor and the control and protection system.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a reactive power compensation device based on IGCT and anti-parallel thyristors, the device comprises at least one group of reactive power compensation circuits, the reactive power compensation circuits comprise an IGCT driving module, a thyristor, a charging voltage equalizing module and an energy-taking power supply module; the IGCT driving module works in coordination with the anti-parallel thyristors to control the on and off of the forward current and the on of the reverse current, thereby ensuring the accuracy and timeliness of switching; at the same time, the introduction of the charging voltage equalizing module and the energy-taking power supply module ensures the balance of the series voltages at each level in the dynamic circuit and the stable power supply of the driving module, thereby improving the performance and reliability of the entire device; the use of the device can achieve a faster switching response, and can accurately control the switching phase, thereby avoiding the problem of system voltage and current overshoot caused by improper switching phase; in addition, the device has bidirectional pressure-bearing and bidirectional conduction characteristics, the opening and closing accuracy is at the microsecond level, can replace the circuit breaker switching mode, the switching does not have an impact on the system, and is applied in the power system to achieve fast and friendly control of high voltage and large current.

[0017] Preferably, in the present invention, damping resistors and damping capacitors are introduced into the charging voltage equalization module, which helps to suppress overvoltage and overcurrent phenomena that may occur in the circuit and protect circuit components from damage; at the same time, this design also helps to improve the charging efficiency and stability of the energy-taking power supply module, ensuring that the driving module obtains a continuous and stable power supply.

[0018] Preferably, in the present invention, the IGCT and the thyristor are connected in reverse parallel, which ensures that the IGCT and the thyristor can control the conduction of the forward and reverse currents respectively, thereby achieving more accurate current control. In addition, it also helps to improve the reliability and stability of the circuit.

[0019] Preferably, in the present invention, by connecting multiple groups of reactive power compensation circuits in series, the capacity and accuracy of reactive power compensation can be further improved, which helps to meet the reactive power compensation needs of larger-scale power systems and also helps to improve the stability and efficiency of the power system.

[0020] Preferably, in the present invention, multiple groups of reactive power compensation circuits are electrically connected to the control and protection system, so that remote monitoring and control of the reactive compensation device can be achieved; this design helps to timely discover and handle abnormal conditions in the circuit, ensuring the safe and stable operation of the power system; at the same time, it also helps to improve the automation and intelligence level of reactive compensation.

[0021] Preferably, in the present invention, a static voltage equalizing module is added to the reactive power compensation circuit, so that the voltage conditions of each level of the reactive power compensation circuit can be monitored in real time, and corresponding measures can be taken to maintain the balance of the series voltages of each level in the static circuit; this helps to further improve the reliability and stability of the circuit, and avoid circuit failure or damage caused by voltage imbalance; at the same time, it can also improve the accuracy and efficiency of reactive power compensation.

[0022] The present invention also provides a working method of a reactive power reinforcement device based on IGCT and anti-parallel thyristors. This method charges the energy-taking power supply module through a charging voltage equalization module and maintains the balance of the series voltages of each level in the dynamic circuit, thereby ensuring the stable power supply of the driving module; the driving module accurately monitors and controls the IGCT, so that the IGCT can be used as a reference positive direction of the AC voltage to quickly and accurately control the conduction and shutdown of the forward current; at the same time, the thyristor is used as a reference to the reverse direction of the positive direction to effectively control the conduction of the reverse current; the use of this working method not only significantly improves the switching response speed, but also can accurately control the switching phase, thereby effectively avoiding the system voltage and current overshoot problem caused by improper switching phase, and improving the stability and safety of the power system.

[0023] The present invention also provides a monitoring method for a reactive power compensation device based on IGCT and anti-parallel thyristors. The monitoring method realizes rapid compensation of reactive power by real-time monitoring of the AC voltage of the power system and accurately controlling the on and off of the IGCT and the thyristors according to the voltage change. When the AC voltage exceeds the set threshold, the IGCT responds quickly and conducts forward current, effectively reducing the voltage of the reactive power compensation device. When the voltage drops below another set threshold, the thyristor conducts reverse current to reduce the voltage of the reactive power compensation device. That is to say, when the system AC voltage drops below the set threshold, the IGCT responds quickly and conducts current to increase the reactive output of the capacitor group system and effectively increase the system voltage. When the system voltage recovers to above another set threshold, the IGCT is turned off and the reactive power compensation device exits conduction. The monitoring method not only significantly improves the switching response speed, but also can accurately control the switching timing, effectively avoiding the system voltage and current overshoot caused by improper switching phase, thereby enhancing the stability and safety of the power system.

[0024] Preferably, in the present invention, the control pulse output by the control and protection system is used to control the IGCT and the thyristor, so that the control process is more accurate and reliable; and the control pulse is identified by the pulse width difference, which further ensures the accurate control and regulation of the control process. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A schematic diagram of a reactive power compensation device based on IGCT and anti-parallel thyristor provided in an embodiment of the present invention; Figure 2 A schematic structural diagram of a reactive power compensation device based on IGCT and anti-parallel thyristor provided in an embodiment of the present invention; Figure 3 A schematic diagram of a small current test circuit of a reactive power compensation device based on IGCT and anti-parallel thyristors provided in an embodiment of the present invention; Figure 4 A schematic diagram of the control timing of a small current test provided by an embodiment of the present invention; Figure 5 A schematic diagram of a high current test circuit of a reactive power compensation device based on IGCT and anti-parallel thyristors provided in an embodiment of the present invention; Figure 6 A flow chart of the control timing of a high current test provided by an embodiment of the present invention; Figure 7 A schematic diagram of the working connection of a reactive power reinforcement device based on IGCT and anti-parallel thyristor provided in an embodiment of the present invention.

[0026] Reference numerals: 1-1, IGCT; 1-2, drive module; 2, thyristor; 3, energy supply module; 4, damping resistor; 5, damping capacitor; 6, static voltage equalizing resistor; 7, control and protection system; 8, first trigger optical fiber; 9, feedback optical fiber; 11, second trigger optical fiber; 12, load; 13, voltage regulator; 14, closing switch. DETAILED DESCRIPTION

[0027] In order to make the technical problems, technical solutions and beneficial effects solved by the present invention more clearly understood, the present invention is further described in detail in the following specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions 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. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0030] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0031] In the description of the embodiments of the present invention, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the invention is usually placed when in use, it is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0032] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0033] In the description of the embodiments of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] The technical terms involved in the invention are explained as follows: IGCT (Integrated Gate-Commutated Thyristor) is the abbreviation of integrated gate-commutated thyristor, which is a high-voltage and high-power semiconductor switching device.

[0035] The full name of VBE is Valve Base Electronics, which is the interface between the control system and the thyristor valve, and is an electronic circuit at ground potential.

[0036] Example As mentioned in the background technology, the switching method of traditional switch circuit breakers has a slow response speed and cannot accurately control the switching phase, which can easily cause improper switching phase and lead to system voltage and current overshoot, making it impossible to ensure reliable and precise control.

[0037] In order to solve the above problems, the present invention provides a reactive power strengthening device based on IGCT and anti-parallel thyristor. The device can replace the circuit breaker switch and be used in parallel with the capacitor bank. It has the ability of fast response and precise phase control, and does not generate voltage and current impact on the system during switching. The main working principle is that when the AC system voltage drops to the set threshold, the reactive power strengthening device is triggered, and part of the capacitor bank is bypassed, thereby generating more reactive power to support system recovery. After the system voltage is restored, the reactive power strengthening device is controlled to be turned off, and the capacitor restores its original capacitance and reactive power.

[0038] The present invention is further described in detail below with reference to the accompanying drawings and embodiments: like Figure 1 As shown, this embodiment provides a reactive power compensation device based on IGCT and anti-parallel thyristor, the device includes at least one group of reactive power compensation circuits, the circuit specifically includes: IGCT drive module, thyristor 2, charging voltage equalization module, energy supply module 3 and static voltage equalization module; wherein, the IGCT drive module includes a connected IGCT1-1 and a drive module 1-2.

[0039] IGCT1-1 in the IGCT drive module is a reference to the positive direction, realizing the functions of forward current control conduction and forward current control shutdown. IGCT1-1, upper anode, lower cathode; thyristor 2 uses a light-triggered thyristor; upper cathode, lower anode.

[0040] The thyristor 2 is anti-parallel connected to both ends of the IGCT 1 - 1 as a reference to the reverse direction of the positive direction, so as to realize the function of reverse current control conduction.

[0041] The damping resistor 4 and the damping capacitor 5 are connected in series and used as a charging voltage equalization module to maintain the uniformity of the multi-stage series voltage in the dynamic (AC) circuit, reduce the voltage deviation of each stage, and at the same time serve as an energy extraction branch to charge the energy extraction power supply module 3.

[0042] The energy-taking power supply module 3 provides working power to the driving modules 1-2 in the IGCT driving module, and maintains monitoring and control of the IGCT.

[0043] The static voltage balancing module adopts a static voltage balancing resistor 6, which can maintain the uniformity of the multi-stage series voltage in the static (DC) circuit and reduce the static deviation of each stage voltage. At the same time, it can be used as a detection branch and connected in series with the sampling resistor of the driving module 1-2 in the GCT driving module to realize each stage voltage detection as the basis of the control logic.

[0044] In this embodiment, the high-power IGCT device and the light-triggered thyristor are connected in anti-parallel. The IGCT is a reverse resistance device that can withstand high voltage in both directions, has the function of active forward opening and active shutdown, and is triggered by electrical triggering; the light-triggered thyristor can withstand high voltage in both directions, has the function of active forward opening, does not have the function of active shutdown, and is triggered by direct light triggering; the functions of the two devices are combined to be connected in anti-parallel to achieve bidirectional active control of conduction and unidirectional active shutdown functions, with high power and high current properties, as a bidirectional switch, it has the ability to accurately control the opening and closing of the microsecond phase, and at the same time has the ability to withstand high voltage and high current. During the switching process, the initial energy storage of the reactive power compensation device is constantly consumed, and it needs to have a switching capability of a certain length of time (such as 10s) in the power system application. In addition, the use of this device greatly reduces the requirements for the power grid power of the test system.

[0045] like Figure 2 As shown, the reactive power compensation device based on IGCT and anti-parallel thyristor includes multiple groups of reactive power compensation circuits; that is, the multiple groups of reactive power compensation circuits adopt a multi-stage series connection mode, and the number of series connection stages is determined according to the system voltage level requirements. Each stage can share a set of damping circuits and static voltage equalizing circuits, which greatly simplifies the circuit topology and can realize multi-stage series use.

[0046] like Figure 7As shown, this embodiment also provides a working method of a reactive power compensation device based on IGCT and anti-parallel thyristors. The reactive power compensation device is connected in parallel next to the capacitor, and the corresponding number of reactive power compensation devices can be configured according to the capacity of the AC system to achieve group switching.

[0047] When the AC system voltage fails and voltage drops, the corresponding number of groups will be put into operation according to the fault depth, so that the capacitor group can generate more reactive power to support the AC grid voltage. When the AC voltage recovers, the reactive power compensation device will be cut off.

[0048] This method charges the energy-taking power supply module through the charging voltage-equalizing module and maintains the balance of the series voltages at all levels in the dynamic circuit, thereby ensuring the stable power supply of the driving module; the driving module accurately monitors and controls the IGCT, so that the IGCT can be used as a reference to the positive direction of the AC voltage to quickly and accurately control the conduction and shutdown of the forward current; at the same time, the thyristor is used as a reference to the reverse direction of the positive direction to effectively control the conduction of the reverse current; the use of this working method not only significantly improves the switching response speed, but also can accurately control the switching phase, thereby effectively avoiding the system voltage and current overshoot problem caused by improper switching phase, and improving the stability and safety of the power system. This device can be used for switching capacitor banks. When the grid voltage drops, it quickly provides voltage support and increases the grid voltage. After the grid voltage is restored, it exits operation at the appropriate voltage and current phase moment, does not cause impact on the equipment, and enhances the stability of the grid.

[0049] like Figure 3 As shown, this embodiment also provides a monitoring method for a reactive power compensation device based on IGCT and anti-parallel thyristor. This monitoring method can be applied to a small current test circuit, and is specifically implemented as follows: This monitoring method is implemented in a test loop as low as 5kVA level, which can be directly connected to the mains 220V to reduce the cost of the test equipment. The reactive power compensation device applies AC power in series with the load 12 to perform a single-stage functional test. The energy supply module 3 connects the drive module 1-2 and the thyristor 2 through optical fiber to control the on and off. The IGCT1-1 needs to be connected to the first trigger optical fiber 8 and the feedback optical fiber 9, and the thyristor 2 only needs to be connected to the second trigger optical fiber 11.

[0050] During the monitoring process of the entire test, the switch 14 (K) is closed, the secondary voltage of the voltage regulator 13 is adjusted to about 1kV, and the load resistance is 500Ω. At this time, the drive module 1-2 obtains energy through the energy supply module 3. After 5-10s, the energy storage is completed, and the IGCT1-1 enters the normal working state and has the two-way conduction condition for a certain time (20s) until the next energy storage level triggers the cycle.

[0051] like Figure 4As shown, the monitoring method of the reactive power compensation device based on IGCT and anti-parallel thyristor includes the following steps: When it is monitored that the AC voltage of the power system exceeds the first threshold, IGCT1-1 feeds back a positive signal; At the next moment, according to the received first trigger conduction signal, IGCT1 - 1 conducts the forward current, so that the AC voltage decreases; At another moment, according to the received shutdown signal, IGCT1-1 shuts off the forward current and changes the conduction state to the blocking state; When it is monitored that the AC voltage of the power system is lower than the second threshold, IGCT1-1 feeds back a reverse signal; At the next moment, according to the received second trigger conduction signal, the thyristor 2 conducts the reverse current, so that the AC voltage increases.

[0052] When it is subjected to AC voltage, its working logic sequence can be shown in the figure below. At t0, the voltage crosses zero and begins to bear positive voltage. When the voltage U of the reactive power compensation device exceeds +50V (adjustable) (at t1), IGCT1-1 feeds back a 10μs signal to VBE7, indicating that the voltage direction of IGCT1-1 is positive, and IGCT1-1 has the triggering and conducting conditions. It can be seen that the voltage of the light-triggered thyristor 2 is reverse; at t2, VBE7 sends a trigger signal to IGCT1-1, IGCT1-1 is turned on, the voltage drops to 0, and the current gradually increases; if a shutdown signal is sent to IGCT1-1 at t3, the forward current drops to 0, the voltage U starts to rise, and it changes from the conduction state to the blocking state. When it is detected that its voltage is lower than -50V (adjustable) (at t4), IGCT1-1 feeds back a 20μs signal to VBE7, indicating that the voltage of the light-triggered thyristor 2 is positive and has the forward triggering capability, and it can be seen that the voltage of IGCT1-1 is reverse. At time T5, 7 sends a trigger signal to the light-triggered thyristor 2, the light-triggered thyristor 2 is turned on, the voltage drops to 0, and the current gradually increases; the control pulse is identified by the pulse width difference, the trigger turn-on signal of IGCT1-1 is a 3μs double pulse signal with an interval of 10μs, the trigger turn-on signal of the light-triggered thyristor 2 is a 10μs single pulse signal, and the active control shutdown signal of IGCT1-1 is a 3μs single pulse signal, thereby realizing voltage state detection and control.

[0053] It can be seen that this monitoring method has no requirements for grid power and can be tested after repeated charging. When conducting a large current active shutdown test, the following circuit can be used to simulate the condition of the device exiting operation at the maximum current (90° phase) during operation.

[0054] like Figure 5As shown, this embodiment also provides a large current test circuit using a reactive power compensation device based on IGCT and anti-parallel thyristor, wherein Ud is a DC power supply, providing a charging DC voltage for the capacitor C; K1 is a switch, used to close and cut off the power branch; CT is a current transformer, used to measure the loop current; C is a capacitor, which forms an oscillation circuit with the L inductor to provide an oscillating sinusoidal large current; K3 is a switch, R is a discharge resistor, used to release the residual energy on the capacitor C; PT is a voltage transformer, used to measure the voltage on the capacitor; K4 is a switch, used to close and disconnect the LC oscillation circuit; S is a test reactive power compensation device, connected to the VBE control device; AC is an AC power supply, used to provide initial energy storage for S, and forms an initial energy storage branch with K2.

[0055] The above loop is designed for series resonance, the operating frequency is designed to be 50Hz, the maximum peak current of the loop exceeds 5kA, which meets the design requirements, and the loop resistance is reduced as much as possible to reduce the energy loss during oscillation. The monitoring method is as follows: First, open switches K2, K3, and K4, close K1, and the DC power supply charges capacitor C; After the capacitor C is charged to the predetermined voltage U0, the switch K1 is opened and the switch K2 is closed, and the AC power supply charges the reactive power compensation device of the test product to make it reach the working state; After the test product enters the working state, disconnect K2 and close K4 to obtain the triggering capability.

[0056] Then enter the VBE control sequence, and its control sequence method is shown in Figure 6.

[0057] In summary, the present invention provides a reactive power compensation device and method based on IGCT and anti-parallel thyristor, which has the following advantages over the prior art: First, the device has bidirectional pressure-bearing and bidirectional conduction characteristics, and the opening and closing accuracy is at the microsecond level. It can replace the circuit breaker switching method, and the switching does not produce an impact on the system. When used in the power system, it can achieve fast and friendly control of high voltage and large current.

[0058] Second, since the IGCT device integrates the control circuit (drive), the use of light-controlled thyristors as the anti-parallel stage can realize the sharing of the damping circuit and the static voltage-equalizing circuit, without the need to set up two sets of control circuits, thus saving costs.

[0059] Third, the use of two sets of test circuits can respectively test the low-power long-term switching function, and the large current triggering and active shutdown function of the device, greatly reducing the power requirements of the test system and completing the functional test.

[0060] The above embodiment is only one of the implementation methods that can realize the technical solution of the present invention. The scope of protection claimed by the present invention is not limited only to this embodiment, but also includes changes, replacements and other implementation methods that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention.

Claims

1. A reactive power compensation device based on IGCT and anti-parallel thyristor, characterized in that: It includes at least one set of reactive power compensation circuit; The reactive power compensation circuit comprises: an IGCT drive module, a thyristor (2), a charging voltage equalization module and an energy-taking power supply module (3); The charging voltage balancing module is used to charge the energy extraction power supply module (3) and to maintain the balance of the series voltages of each level in the dynamic circuit; The IGCT driving module comprises a connected IGCT (1-1) and a driving module (1-2); The IGCT (1-1) serves as a reference positive direction of the AC voltage and is used to control the forward current to be turned on and off; The thyristor (2) is reversely connected in parallel to the two ends of the IGCT (1-1) and is used as a reference to the reverse direction of the positive direction to control the conduction of the reverse current; The energy extraction power supply module (3) is used to supply power to the drive module (1-2).

2. The reactive power reinforcement device based on IGCT and anti-parallel thyristor according to claim 1 is characterized in that: The charging voltage balancing module comprises a damping resistor (4) and a damping capacitor (5); The damping resistor (4), the damping capacitor (5) and the energy extraction power supply module (3) are sequentially connected in series and then connected in parallel with the IGCT (1-1).

3. The reactive power compensation device based on IGCT and anti-parallel thyristor according to claim 1, characterized in that: The anode of the IGCT (1-1) is connected to the cathode of the thyristor (2), and the cathode of the IGCT (1-1) is connected to the anode of the thyristor (2).

4. The reactive power reinforcement device based on IGCT and anti-parallel thyristor according to any one of claims 1 to 3, characterized in that: The reactive power compensation device comprises a plurality of reactive power compensation circuits, and the plurality of reactive power compensation circuits are connected in series.

5. The reactive power reinforcement device based on IGCT and anti-parallel thyristor according to claim 4 is characterized in that: The plurality of reactive power compensation circuits are electrically connected to the control and protection system (7) respectively.

6. The reactive power compensation device based on IGCT and anti-parallel thyristor according to claim 4, characterized in that: The reactive power compensation circuit also includes a static voltage balancing module; the static voltage balancing module is connected in series with the driving module (1-2) and is used to detect the voltage of each level of the reactive power compensation circuit and to maintain the balance of the series voltage of each level in the static circuit.

7. A working method of a reactive power compensation device based on IGCT and anti-parallel thyristor, characterized in that: The reactive power compensation device based on IGCT and anti-parallel thyristor according to any one of claims 1 to 6 comprises: The charging voltage equalization module charges the energy extraction power supply module (3) and maintains the balance of the series voltages of each level in the dynamic circuit; The energy-taking power supply module (3) supplies power to the drive module (1-2); The driving module (1-2) monitors and controls the IGCT (1-1); The IGCT (1-1) is used as the reference positive direction of the AC voltage to control the conduction and shutdown of the forward current; The thyristor (2) is used as a reference to the reverse direction of the positive direction to control the conduction of the reverse current.

8. A monitoring method for a reactive power compensation device based on IGCT and anti-parallel thyristor, characterized in that: The reactive power compensation device based on IGCT and anti-parallel thyristor according to any one of claims 1 to 6 comprises: When it is monitored that the AC voltage of the power system exceeds a first threshold, the IGCT (1-1) feeds back a positive signal; At the next moment, according to the received first trigger conduction signal, the IGCT (1-1) conducts the forward current, so that the voltage of the reactive power compensation device is reduced; At another moment, according to the received shutdown signal, IGCT (1-1) shuts off the forward current and changes the conduction state to the blocking state; When it is monitored that the AC voltage of the power system is lower than a second threshold, the IGCT (1-1) feeds back a reverse signal; At the next moment, according to the received second trigger conduction signal, the thyristor (2) conducts the reverse current, so that the voltage of the reactive power compensation device is reduced.

9. The monitoring method of the reactive power reinforcement device based on IGCT and anti-parallel thyristor according to claim 8, characterized in that: The IGCT (1-1) and the thyristor (2) are controlled by using a control pulse output by a control and protection system (7); the control pulse comprises a first trigger on signal, a second trigger on signal and a turn-off signal; wherein the pulse widths corresponding to the control pulses are different.

10. The monitoring method of the reactive power compensation device based on IGCT and anti-parallel thyristor according to claim 8, characterized in that: The reactive power compensation circuit is connected in series with the load (12) and the closed switch (14) in the loop of the secondary side of the voltage regulator (13); A first trigger optical fiber (8) and a feedback optical fiber (9) are connected between the IGCT (1-1) and the control and protection system (7); A second trigger optical fiber (11) is connected between the thyristor (2) and the control and protection system (7).

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