Testing device and method for controllable commutation converter valve

Abstract

The invention relates to a testing device and method for a controllable commutation converter valve. The device comprises a current source circuit which is used for providing on-state current for a controllable commutation converter valve under the condition that the controllable commutation converter valve is in an on state; the voltage source circuit is used for providing commutation voltage for the controllable commutation converter valve when the controllable commutation converter valve is in a turn-off state; the active turn-off circuit is used for providing turn-off test current for the controllable commutation converter valve; and the processing module is used for respectively controlling the working states of the current source circuit, the voltage source circuit and the active turn-off circuit, simulating a target test working condition for the controllable commutation converter valve, and collecting electrical parameters of the controllable commutation converter valve under the target test working condition. By adopting the device, a single working condition or a mixed working condition can be simulated for the controllable commutation converter valve, and a mixed operation test can be carried out.

Description

Technical Field

[0001] The present application relates to the field of electric power technology, and in particular to a testing device and method for a controllable phase-changing flow control valve. Background Art

[0002] With the development of power transmission technology, high-voltage direct current transmission technology has emerged. High-voltage direct current transmission technology has the advantages of high voltage level, long transmission distance and large transmission capacity. It is a necessary way to promote the realization of dual carbon goals.

[0003] At present, HVDC transmission uses grid-commutated converters based on thyristor devices. When an AC line fails, there is a commutation failure problem on the inverter side of the converter, which seriously affects the reliability of HVDC transmission. Therefore, with the continuous development of power semiconductor devices, active commutation valves have emerged. Compared with grid-commutated converters based on thyristor devices, active commutation valves have the function of active shutdown, so that in the event of an AC fault, they can be actively shut down to achieve controllability of commutation, greatly improving the reliability of the HVDC transmission system. However, in order to ensure the reliable and stable operation of active commutation valves in actual engineering applications, it is necessary to test the active commutation valves first. Summary of the invention

[0004] Based on this, it is necessary to provide a test device and method for a controllable phase-changing valve that can test the performance and reliability of an active phase-changing valve in order to solve the above technical problems.

[0005] A test device for a controllable phase-changing flow control valve, the device comprising:

[0006] a current source circuit connected to the controllable phase-changing valve, and used for providing an on-state current to the controllable phase-changing valve when the controllable phase-changing valve is in an on state;

[0007] a voltage source circuit connected to the controllable phase-changing valve, and used for providing a phase-changing voltage to the controllable phase-changing valve when the controllable phase-changing valve is in an off state;

[0008] An active shut-off circuit, connected to the controllable phase-changing valve, for providing a shut-off test current for the controllable phase-changing valve when the controllable phase-changing valve is in a conducting state;

[0009] A processing module is respectively connected to the current source circuit, the voltage source circuit, the active shutdown circuit, and the controllable phase-changing valve, and is used to respectively control the working states of the current source circuit, the voltage source circuit, and the active shutdown circuit, simulate a target test condition for the controllable phase-changing valve, and collect electrical parameters of the controllable phase-changing valve under the target test condition, wherein the electrical parameters are used to determine the test results of the controllable phase-changing valve, and the target test condition includes at least one of an active shutdown test condition and a phase-changing shutdown test condition.

[0010] In one embodiment, the active shutdown circuit includes: a first DC power supply, a first energy storage unit, a first switch unit, and a first discharge output unit, wherein: the first DC power supply is connected in parallel with the first energy storage unit to charge the first energy storage unit; the first energy storage unit is used to store electrical energy; the first switch unit is arranged in series between the positive electrode of the controllable phase-changing valve and the first energy storage unit to control the conduction or disconnection of the passage between the positive electrode of the controllable phase-changing valve and the first energy storage unit; the first discharge output unit is arranged in series between the positive electrode of the controllable phase-changing valve and the first energy storage unit, so that the first energy storage unit provides a stable shutdown test current for the controllable phase-changing valve.

[0011] In one embodiment, the first energy storage unit includes a first capacitor, the first switch unit includes a first controllable valve, and the first discharge output unit includes a first inductor, a second inductor and a freewheeling diode. The first capacitor is connected in parallel with the first DC power supply, the positive electrode of the first controllable valve is connected to the first end of the first capacitor, the negative electrode of the first controllable valve is connected to the first end of the first inductor, the second end of the first inductor is connected to the positive electrode of the controllable phase-changing valve, the second end of the first capacitor is connected to the negative electrode of the controllable phase-changing valve, the second inductor is connected in series between the positive electrode of the first controllable valve and the first end of the first capacitor, the positive electrode of the freewheeling diode is connected to the positive electrode of the first controllable valve, and the negative electrode of the freewheeling diode is connected to the first end of the first capacitor, wherein the first controllable valve is used to be turned on during the process of testing the active shutdown performance of the controllable phase-changing valve, so that the first capacitor discharges to the controllable phase-changing valve through the first inductor to provide the shutdown test current; wherein the controllable phase-changing valve is used to actively shut down when the amplitude of the shutdown test current reaches a first set value.

[0012] In one embodiment, the active shutdown test condition includes a first conduction stage, an active shutdown stage, and a first commutation stage; the processing module controls the current source circuit to provide an on-state current for the controllable commutation valve, and controls the active shutdown circuit to provide a shutdown test current for the controllable commutation valve to simulate the first conduction stage; the controllable commutation valve is actively shut down, and the active shutdown circuit provides a support voltage for the controllable commutation valve to simulate the active shutdown stage; the processing module controls the voltage source circuit to provide a commutation voltage for the controllable commutation valve to simulate the first commutation stage.

[0013] In one embodiment, the voltage source circuit includes: a second DC power supply, a second switch unit, a voltage polarity reversal unit, a second energy storage unit, a phase change unit, a second discharge output unit, and a third energy storage unit, wherein the positive electrode of the second DC power supply is connected to the first end of the second switch unit, the second end of the second switch unit is connected to the first end of the voltage polarity reversal unit, the negative electrode of the second DC power supply is respectively connected to the second end of the voltage polarity reversal unit and the negative electrode of the controllable phase-changing valve, the second energy storage unit is connected in parallel with the voltage polarity reversal unit, the phase change unit is connected in series between the second energy storage unit and the positive electrode of the controllable phase-changing valve, the second discharge output unit is connected in series between the second energy storage unit and the positive electrode of the controllable phase-changing valve, and the third energy storage unit is connected in parallel with the controllable phase-changing valve; wherein the voltage polarity reversal unit is used to adjust the polarity of the voltage on the second energy storage unit; and the phase change unit is used to adjust the polarity of the voltage applied to the controllable phase-changing valve.

[0014] In one embodiment, the second switch unit includes a second controllable valve, the second energy storage unit includes a second capacitor, the third energy storage unit includes a third capacitor, and the second discharge output unit includes a third inductor. The positive electrode of the second DC power supply is connected to the positive electrode of the second controllable valve, the negative electrode of the second controllable valve is connected to the first end of the voltage polarity reversal unit, the negative electrode of the second DC power supply is respectively connected to the second end of the voltage polarity reversal unit and the negative electrode of the controllable phase-changing valve, the second capacitor is connected to the voltage polarity reversal unit in parallel, the first end of the phase-changing unit is connected to the first end of the second capacitor, the second end of the phase-changing unit is connected to the first end of the third inductor, the second end of the third inductor is connected to the positive electrode of the controllable phase-changing valve, and the third capacitor is connected to the controllable phase-changing valve in parallel.

[0015] In one embodiment, the voltage polarity reversal unit includes: a fourth inductor, a third controllable valve, and a fourth controllable valve, wherein the first end of the fourth inductor is connected to the negative electrode of the second controllable valve, the second end of the fourth inductor is respectively connected to the first end of the phase switching unit and the first end of the second capacitor, the second end of the second capacitor is connected to the negative electrode of the second DC power supply, the positive electrode of the third controllable valve is respectively connected to the negative electrode of the fourth controllable valve and the negative electrode of the second DC power supply, and the negative electrode of the third controllable valve is respectively connected to the positive electrode of the fourth controllable valve and the first end of the fourth inductor; wherein the third controllable valve and the fourth controllable valve are used for time-sharing conduction to adjust the polarity of the voltage on the second capacitor.

[0016] In one embodiment, the phase-changing unit includes: a fifth controllable valve and a sixth controllable valve, wherein the positive electrode of the fifth controllable valve is respectively connected to the negative electrode of the sixth controllable valve and the first end of the second capacitor, and the negative electrode of the fifth controllable valve is respectively connected to the positive electrode of the sixth controllable valve and the first end of the third inductor; wherein the fifth controllable valve and the sixth controllable valve are used for time-sharing conduction to adjust the polarity of the voltage applied to the controllable phase-changing valve.

[0017] In one embodiment, the current source circuit includes: a power supply and a rectifier-inverter circuit, the rectifier-inverter circuit is respectively connected to the power supply and the controllable phase-changing valve, and the rectifier-inverter circuit is used to be equivalent to the current stress of the controllable phase-changing valve under the power supply of the power supply.

[0018] In one of the embodiments, the device further includes an isolation valve, which is respectively connected to the rectifier-inverter pair circuit and the controllable phase-changing valve, and the isolation valve is used to isolate the rectifier-inverter pair circuit from the controllable phase-changing valve.

[0019] In one embodiment, the isolation valve comprises a reverse-blocking integrated gate-commutated thyristor.

[0020] In one of the embodiments, the test device for the controllable phase-changing flow control valve further includes:

[0021] The impulse voltage circuit is connected to the controllable phase-changing valve and is used to provide an impulse voltage for the controllable phase-changing valve.

[0022] In one embodiment, the impulse voltage circuit includes: an impulse generator and a switch, a spherical gap is provided between the first end of the impulse generator and the first end of the switch, the second end of the impulse generator is connected to the negative pole of the controllable phase-changing valve, and the second end of the switch is connected to the positive pole of the controllable phase-changing valve.

[0023] In one of the embodiments, the test device of the controllable phase-changing valve further includes: a fault current circuit connected to the controllable phase-changing valve and used to provide a fault current for the controllable phase-changing valve.

[0024] In one embodiment, the fault current circuit includes: a fault power supply, a fourth capacitor, a fifth inductor, and a seventh controllable valve. The fault power supply is connected in parallel with the fourth capacitor, the first end of the fifth inductor is connected to the first end of the fourth capacitor, the second end of the fifth inductor is connected to the positive electrode of the seventh controllable valve, the negative electrode of the seventh controllable valve is connected to the positive electrode of the controllable phase-changing valve, and the second end of the fourth capacitor is connected to the negative electrode of the controllable phase-changing valve.

[0025] A method for testing a controllable phase-changing valve, the method being applied to the aforementioned test device for the controllable phase-changing valve, the method comprising:

[0026] respectively controlling the working states of the current source circuit and the voltage source circuit to simulate a switching disconnection test condition for the controllable phase-changing valve;

[0027] Respectively controlling the working states of the current source circuit, the voltage source circuit, and the active shutdown circuit, and controlling the controllable phase-changing valve to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable phase-changing valve;

[0028] Acquiring electrical parameters of the controllable phase-changing valve under a target test condition, wherein the target test condition includes at least one of an active shut-off test condition and a phase-changing shut-off test condition;

[0029] A test result of the controllable phase-changing valve is determined based on the electrical parameters.

[0030] In one embodiment, the active shutdown test condition includes a first conduction stage, an active shutdown stage, and a first commutation stage; the operating states of the current source circuit, the voltage source circuit, and the active shutdown circuit are controlled respectively, and the controllable commutation valve is controlled to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable commutation valve, including:

[0031] Controlling the current source circuit to provide an on-state current for the controllable phase-changing valve, controlling the active shut-off circuit to provide a shut-off test current for the controllable phase-changing valve, and controlling the controllable phase-changing valve to actively shut down when the amplitude of the shut-off test current reaches a first set value, so as to simulate the first conduction stage;

[0032] The controllable phase-changing valve is actively shut down, and the active shut-down circuit provides a support voltage for the controllable phase-changing valve to simulate the active shut-down stage;

[0033] The voltage source circuit is controlled to provide a switching voltage for the controllable switching valve to simulate the first switching stage.

[0034] The above-mentioned test device and method for the controllable phase-changing valve. By setting a current source circuit, it is possible to provide an on-state current for the controllable phase-changing valve, so as to facilitate simulating the current received by the controllable phase-changing valve when it is normally turned on, thereby simulating the working conditions of the controllable phase-changing valve when it is normally turned on. By setting a voltage source circuit, it is possible to provide a switching voltage for the controllable phase-changing valve, and the polarity of the switching voltage can be reversed, so as to simulate the working conditions of the controllable phase-changing valve during the normal shutdown process. Thus, the current source circuit and the voltage source circuit are used in combination to simulate the working conditions of the controllable phase-changing valve when it is normally working. By setting an active shutdown circuit, it is possible to provide a shutdown test current for the controllable phase-changing valve, and the shutdown test current is used as the test current for the active shutdown of the controllable phase-changing valve. When the controllable phase-changing valve is normally working, the test conditions required for the active shutdown test condition can be simulated for the controllable phase-changing valve, which is convenient for testing the active shutdown performance of the controllable phase-changing valve. By setting the processing module, the working states of the current source circuit, the voltage source circuit, and the active shutdown circuit are controlled respectively, and the target test condition is simulated for the controllable phase-changing valve. That is, the current source circuit and the voltage source circuit can be used in combination to simulate the phase-changing shutoff test condition for the controllable phase-changing valve, and then the electrical parameters of the controllable phase-changing valve under the phase-changing shutoff test condition are collected, and the current source circuit, the voltage source circuit, and the active shutdown circuit can be used in combination to simulate the active shutdown test condition for the controllable phase-changing valve. In summary, the device of the present application can be used to simulate a single condition or a mixed condition for the controllable phase-changing valve, and a mixed operation test can be carried out, so as to facilitate the collection of the electrical parameters of the controllable phase-changing valve under the active shutdown test condition. It is convenient to determine the test results of the controllable phase-changing valve through the collected electrical parameters, and then judge the performance and reliability of the controllable phase-changing valve, thereby realizing the test of the controllable phase-changing valve. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0036] FIG1 is a schematic diagram of a structure of a test device for a controllable phase-changing valve according to an embodiment;

[0037] FIG2 is a second structural schematic diagram of a test device for a controllable phase-changing flow control valve in one embodiment;

[0038] FIG3 is a third structural schematic diagram of a test device for a controllable phase-changing valve in one embodiment;

[0039] FIG4 is a fourth structural schematic diagram of a test device for a controllable phase-changing flow control valve in one embodiment;

[0040] FIG5 is a current and voltage waveform diagram of a test device in an active shutdown test condition in one embodiment;

[0041] FIG6 is a current and voltage waveform diagram of a test device in a switching disconnection test condition in one embodiment;

[0042] FIG7 is a fifth structural schematic diagram of a test device for a controllable phase-changing valve in one embodiment;

[0043] FIG8 is a sixth structural schematic diagram of a test device for a controllable phase-changing valve in one embodiment;

[0044] FIG9 is a flow chart of a method for testing a controllable phase-changing valve in one embodiment;

[0045] FIG. 10 is a flow chart of an active shutdown test method for a controllable phase-changing valve in one embodiment.

[0046] Description of reference numerals:

[0047] 10-current source circuit, 20-voltage source circuit, 30-active shutdown circuit, 40-processing module, 50-controllable phase-changing valve, 31-first DC power supply, 32-first energy storage unit, 33-first switch unit, 34-first discharge output unit, 21-second DC power supply, 22-second switch unit, 23-voltage polarity reversal unit, 24-second energy storage unit, 25-phase-changing unit, 26-second discharge output unit, 27-third energy storage unit, 11-power supply, 12-rectifier-inverter pair-drag circuit, 121-first three-phase full-bridge rectifier circuit, 122-second three-phase full-bridge rectifier circuit, 60-impulse voltage circuit, 61-impulse generator, 70-fault current circuit, 71-fault power supply. DETAILED DESCRIPTION

[0048] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0049] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0050] It can be understood that the terms "first", "second", etc. used in the present application can be used in this article to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from another element.

[0051] It should be noted that when an element is considered to be "connected" to another element, it can be directly connected to the other element, or connected to the other element through an intermediate element. In addition, the "connection" in the following embodiments should be understood as "electrical connection", "communication connection", etc. if there is transmission of electrical signals or data between the connected objects.

[0052] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" etc. specify the presence of stated features, wholes, steps, operations, components, parts or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof.

[0053] In one embodiment, as shown in FIG1 , a test device for a controllable phase-changing valve is provided, the device comprising: a current source circuit 10, a voltage source circuit 20, an active shutdown circuit 30, and a processing module 40, wherein:

[0054] The current source circuit 10 is connected to the controllable phase-changing valve 50 and is used to provide an on-state current to the controllable phase-changing valve 50 when the controllable phase-changing valve 50 is in an on state.

[0055] Among them, the current source circuit 10 can provide a steady-state DC current for the controllable phase-changing valve 50, thereby simulating the current flowing through the controllable phase-changing valve 50 when it is in a normal conduction state, simulating the actual working conditions, and facilitating testing of the controllable phase-changing valve 50.

[0056] Exemplarily, the controllable phase-changing valve 50 is turned on for at least one third of the time (6.67 ms) in one power frequency cycle (eg, 20 ms). The on-state current provided by the current source circuit 10 may be 1000A-7000A.

[0057] Among them, the controllable phase-commutated commutator valve 50 may include at least one reverse-resistance integrated gate commutated thyristor (IGCT), and may also include multiple reverse-resistance IGCTs connected in series. Commutation failure is one of the common faults on the inverter side of the DC transmission system. It will cause adverse consequences such as reduced DC voltage, reduced transmission power, increased current, damage to DC converter station equipment, and overvoltage of the AC system on the inverter side. In a multi-input DC system, a single AC fault can cause multiple DC commutation failures in a large range, resulting in a power shock of tens of millions of kilowatts, which seriously threatens the safe operation of the power grid. The controllable phase-commutated commutator valve 50 can achieve controllable active shutdown. It not only has the characteristics of large capacity and low loss of thyristors, but also has the ability of active shutdown, so that it can actively shut down under AC faults to achieve controllable commutation, which essentially solves the problem of commutation failure.

[0058] The voltage source circuit 20 is connected to the controllable phase-switching valve 50 and is used to provide a switching voltage to the controllable phase-switching valve 50 when the controllable phase-switching valve 50 is in an off state.

[0059] The voltage source circuit 20 can provide a transient recovery voltage, i.e., a commutation voltage, when the controllable commutation valve 50 is turned off, thereby simulating the voltage condition that the controllable commutation valve 50 is subjected to during actual use. The polarity of the commutation voltage provided by the voltage source circuit 20 can be actively reversed, thereby simulating various actual working conditions for the controllable commutation valve 50 according to actual needs.

[0060] The active shut-off circuit 30 is connected to the controllable phase-changing valve 50 and is used to provide a shut-off test current to the controllable phase-changing valve 50 when the controllable phase-changing valve 50 is in the on state.

[0061] Among them, when the controllable phase-changing valve 50 is in the off state, the active shutdown circuit 30 can continue to provide a certain continuous current to the controllable phase-changing valve 50, and the current charges the parasitic capacitance of the controllable phase-changing valve 50, and the parasitic capacitance provides a supporting voltage for the controllable phase-changing valve 50.

[0062] The shutdown test current is a large current, and the active shutdown circuit 30 needs to be powered by a high-voltage capacitor to output a sinusoidal current. The amplitude of the shutdown test current is generally 1 kA~10 kA, and the pulse width is about 1 ms.

[0063] The processing module 40 is respectively connected to the current source circuit 10, the voltage source circuit 20, the active shutdown circuit 30, and the controllable phase-changing valve 50, and is used to control the working states of the current source circuit 10, the voltage source circuit 20, and the active shutdown circuit 30, respectively, simulate the target test conditions for the controllable phase-changing valve 50, and collect the electrical parameters of the controllable phase-changing valve 50 under the target test conditions.

[0064] The electrical parameters are used to determine the test results of the controllable phase-changing valve 50, and the target test conditions include at least one of an active shutdown test condition and a phase-changing shutdown test condition.

[0065] Among them, the processing module 40 can control the working status of the current source circuit 10 and the voltage source circuit 20, so as to simulate the switching disconnection test condition for the controllable phase-changing valve 50, that is, the current and voltage stress that the controllable phase-changing valve 50 is subjected to during the entire process of normal switching disconnection, and then collect the electrical parameters (such as voltage, current, disconnection timing, etc.) of the controllable phase-changing valve 50 during the entire process to see whether they match or are consistent with the theoretically preset electrical parameters, so as to verify the reliability and performance of the controllable phase-changing valve 50.

[0066] Among them, the processing module 40 can control the working state of the current source circuit 10, the voltage source circuit 20, and the active shutdown circuit 30, so as to simulate the active shutdown test condition for the controllable phase-changing valve 50, that is, the controllable phase-changing valve 50 combines the active shutdown process with the normal phase-changing disconnection process, simulates the current and voltage stress it bears in this process, and then collects the electrical parameters (such as voltage, current, opening and closing timing, etc.) of the controllable phase-changing valve 50 in the whole process to see whether they match or are consistent with the theoretical preset electrical parameters, so as to verify the reliability and performance of the controllable phase-changing valve 50. Through the control of the processing module 40, a single working condition or a mixed working condition can be simulated for the controllable phase-changing valve 50 to conduct a mixed operation test.

[0067] In this embodiment, by providing the current source circuit 10, the on-state current can be provided for the controllable phase-switching valve 50, so as to facilitate the simulation of the current received by the controllable phase-switching valve 50 when it is normally turned on, thereby simulating the normal on-state working condition for the controllable phase-switching valve 50. By providing the voltage source circuit 20, the phase-switching voltage can be provided for the controllable phase-switching valve 50, and the polarity of the phase-switching voltage can be reversed, thereby simulating the working condition in the normal off-state process for the controllable phase-switching valve 50. Thus, the current source circuit 10 and the voltage source circuit 20 are used in combination to simulate the on-state and off-state working conditions for the controllable phase-switching valve 50 during normal operation. By setting up an active shutdown circuit 30, a shutdown test current can be provided for the controllable phase-changing valve 50. The shutdown test current serves as a test current for active shutdown of the controllable phase-changing valve 50. When the controllable phase-changing valve 50 is operating normally, the test conditions required for the active shutdown test condition can be simulated for the controllable phase-changing valve 50, thereby facilitating testing the active shutdown performance of the controllable phase-changing valve 50. By setting the processing module 40, the working states of the current source circuit 10, the voltage source circuit 20, and the active shut-off circuit 30 are controlled respectively, and the target test condition is simulated for the controllable phase-change valve 50, that is, the current source circuit 10 and the voltage source circuit 20 can be used in combination to simulate the phase-change shut-off test condition for the controllable phase-change valve 50, and then the electrical parameters of the controllable phase-change valve 50 under the phase-change shut-off test condition are collected, and the current source circuit 10, the voltage source circuit 20, and the active shut-off circuit 30 can be used in combination to simulate the active shut-off test condition for the controllable phase-change valve 50, so as to facilitate the collection of the electrical parameters of the controllable phase-change valve 50 under the active shut-off test condition. It is convenient to determine the test result of the controllable phase-change valve 50 through the collected electrical parameters, and then judge the performance and reliability of the controllable phase-change valve 50, so as to realize the test of the controllable phase-change valve 50.

[0068] In one embodiment, as shown in FIG2 , the active shutdown test circuit includes: a first DC power supply 31, a first energy storage unit 32, a first switch unit 33, and a first discharge output unit 34, wherein:

[0069] The first DC power supply 31 is connected in parallel with the first energy storage unit 32 and is used to charge the first energy storage unit 32 .

[0070] The first energy storage unit 32 is used to store electrical energy.

[0071] The first switch unit 33 is arranged in series between the positive electrode of the controllable phase-changing valve 50 and the first energy storage unit 32, and is used to control the conduction or disconnection of the passage between the positive electrode of the controllable phase-changing valve 50 and the first energy storage unit 32.

[0072] The first discharge output unit 34 is arranged in series between the positive electrode of the controllable phase-changing valve 50 and the first energy storage unit 32 , so that the first energy storage unit 32 provides a stable shut-off test current for the controllable phase-changing valve 50 .

[0073] Among them, the processing module 40 is not shown in Figure 2. It can be understood that the working state of each power supply and the conduction state of each valve device in the present application can be controlled by the processing module 40, and the same understanding applies to all embodiments of the present application.

[0074] In this embodiment, by setting a first DC power supply 31, a first energy storage unit 32, a first switch unit 33, and a first discharge output unit 34, a specific structure of an active shutdown test circuit is provided, which can provide a shutdown test current for the controllable phase-changing valve 50.

[0075] In one embodiment, please continue to refer to Figure 2, the first energy storage unit 32 includes a first capacitor C1, the first switch unit 33 includes a first controllable valve V1, and the first discharge output unit 34 includes a first inductor L1, a second inductor L2 and a freewheeling diode D1. The first capacitor C1 is connected in parallel with the first DC power supply 31, the positive electrode of the first controllable valve V1 is connected to the first end of the first capacitor C1, the negative electrode of the first controllable valve V1 is connected to the first end of the first inductor L1, the second end of the first inductor L1 is connected to the positive electrode of the controllable phase-changing valve 50, the second end of the first capacitor C1 is connected to the negative electrode of the controllable phase-changing valve 50, the second inductor L2 is connected in series between the positive electrode of the first controllable valve V1 and the first end of the first capacitor C1, the positive electrode of the freewheeling diode D1 is connected to the positive electrode of the first controllable valve V1, and the negative electrode of the freewheeling diode D1 is connected to the first end of the first capacitor C1.

[0076] The first controllable valve V1 is used to be turned on during the process of testing the active shut-off performance of the controllable phase-changing valve 50, so that the first capacitor C1 discharges to the controllable phase-changing valve 50 through the first inductor L1 to provide a shut-off test current.

[0077] Among them, the first inductor L1, as the switching inductor of the controllable phase-changing valve 50, is a variable inductor, and its inductance value can be adjusted according to the number of reverse resistance type IGCT devices connected in series specifically included in the controllable phase-changing valve 50, so as to simulate a more realistic switching inductance value under actual operating conditions for the controllable phase-changing valve 50. Using an active shutdown test circuit to simulate the operating condition of active shutdown during the operation of the controllable phase-changing valve 50 requires that the current, voltage waveform and shutdown energy are equivalent to the actual situation of the controllable phase-changing valve 50. Therefore, for controllable phase-changing valves 50 with different series connection numbers, in order to ensure the equivalence of shutdown energy, the first inductor L1 needs to be adjustable and can be adjusted based on the number of reverse resistance type IGCT devices connected in series specifically included in the controllable phase-changing valve 50.

[0078] Among them, the second inductor L2 is used as a discharge inductor, and its inductance value is fixed. This is because the pulse width is fixed (the resonant circuit composed of the second inductor L2 and the first capacitor C1, the values ​​of L2 and C1 determine the resonant period), and the safety of the test must also be considered (it is safer when the inductance is large and the capacitance is small, so that the short-circuit current of the controllable phase-changing valve 50 when it fails is small). Therefore, the first inductor L1 and the second inductor L2 are designed in series to increase the loop inductance. At the same time, the second inductor L2 is anti-parallel connected with a freewheeling diode D1. When the controllable phase-changing valve 50 is actively turned off, the current on the second inductor L2 is continued. The controllable phase-changing valve 50 only needs to consume the current on the first inductor L1. The shutdown state is highly equivalent to the actual situation, and the simulated working condition is more realistic.

[0079] The controllable phase-changing valve 50 is used to actively shut down when the amplitude of the shut-off test current reaches a first set value. The first set value may be a value pre-set according to actual test requirements.

[0080] In this embodiment, by designing the first inductor L1 and the second inductor L2, the safety during the active shutdown test is improved, and the design of the first inductor L1 can be adjusted according to the number of reverse resistance type IGCT devices in series included in the controllable phase-changing valve 50, thereby improving the authenticity of the active shutdown test conditions.

[0081] In one embodiment, as shown in FIG3 , the voltage source circuit 20 includes: a second DC power supply 21, a second switch unit 22, a voltage polarity reversal unit 23, a second energy storage unit 24, a phase change unit 25, a second discharge output unit 26, and a third energy storage unit 27. The positive electrode of the second DC power supply 21 is connected to the first end of the second switch unit 22, the second end of the second switch unit 22 is connected to the first end of the voltage polarity reversal unit 23, the negative electrode of the second DC power supply 21 is respectively connected to the second end of the voltage polarity reversal unit 23 and the negative electrode of the controllable phase-changing valve 50, the second energy storage unit 24 is connected in parallel with the voltage polarity reversal unit 23, the phase change unit 25 is connected in series between the second energy storage unit 24 and the positive electrode of the controllable phase-changing valve 50, the second discharge output unit 26 is connected in series between the second energy storage unit 24 and the positive electrode of the controllable phase-changing valve 50, and the third energy storage unit 27 is connected in parallel with the controllable phase-changing valve 50.

[0082] The voltage polarity reversing unit 23 is used to adjust the polarity of the voltage on the second energy storage unit 24. The phase switching unit 25 is used to adjust the polarity of the voltage applied to the controllable phase switching valve 50.

[0083] In this embodiment, a specific structure of a voltage source circuit 20 is provided, which can provide a switching voltage of different polarities to the controllable phase-changing valve 50, thereby simulating the working condition of the controllable phase-changing valve 50 during normal shutdown. By designing the voltage polarity reversal unit 23, the polarity of the voltage on the second energy storage unit 24 can be actively adjusted, so that the polarity of the voltage on the second energy storage unit 24 is consistent with the actual working condition, thereby improving the realism of the simulated working condition.

[0084] In one embodiment, please continue to refer to Figure 3, the second switch unit 22 includes a second controllable valve V2, the second energy storage unit 24 includes a second capacitor C2, the third energy storage unit 27 includes a third capacitor C3, the second discharge output unit 26 includes a third inductor L3, the positive electrode of the second DC power supply 21 is connected to the positive electrode of the second controllable valve V2, the negative electrode of the second controllable valve V2 is connected to the first end of the voltage polarity reversal unit 23, the negative electrode of the second DC power supply 21 is respectively connected to the second end of the voltage polarity reversal unit 23 and the negative electrode of the controllable phase-changing valve 50, the second capacitor C2 is connected in parallel with the voltage polarity reversal unit 23, the first end of the phase-changing unit 25 is connected to the first end of the second capacitor C2, the second end of the phase-changing unit 25 is connected to the first end of the third inductor L3, the second end of the third inductor L3 is connected to the positive electrode of the controllable phase-changing valve 50, and the third capacitor C3 is connected in parallel with the controllable phase-changing valve 50.

[0085] The third capacitor C3 is used to simulate the parasitic capacitance caused by the devices around the controllable phase-changing valve 50 when it is installed in an actual power system, so that the operating conditions of the controllable phase-changing valve 50 during operation are more realistic.

[0086] In this embodiment, the second switch unit 22 includes a second controllable valve V2, the second energy storage unit 24 includes a second capacitor C2, the third energy storage unit 27 includes a third capacitor C3, and the second discharge output unit 26 includes a third inductor L3, thereby providing a specific circuit structure that can achieve the corresponding required functions.

[0087] In one embodiment, please continue to refer to Figure 3, the voltage polarity reversal unit 23 includes: a fourth inductor L4, a third controllable valve V3, and a fourth controllable valve V4. The first end of the fourth inductor L4 is connected to the negative electrode of the second controllable valve V2, the second end of the fourth inductor L4 is respectively connected to the first end of the phase switching unit 25 and the first end of the second capacitor C2, the second end of the second capacitor C2 is connected to the negative electrode of the second DC power supply 21, the positive electrode of the third controllable valve V3 is respectively connected to the negative electrode of the fourth controllable valve V4 and the negative electrode of the second DC power supply 21, and the negative electrode of the third controllable valve V3 is respectively connected to the positive electrode of the fourth controllable valve V4 and the first end of the fourth inductor L4.

[0088] The third controllable valve V3 and the fourth controllable valve V4 are used to conduct in time division to adjust the polarity of the voltage on the second capacitor C2. When the third controllable valve V3 is conducted, the second capacitor C2 discharges to the fourth inductor L4 through the third controllable valve V3. When the second capacitor C2 discharges, the positive current passes through the third controllable valve V3, and the negative current is cut off by the third controllable valve V3. Then, the electric energy generated by the current passing through is stored in the fourth inductor L4, and then the fourth inductor L4 charges the second capacitor C2. The second capacitor C2 and the fourth inductor L4 form a resonant circuit, and the voltage polarity on the second capacitor C2 is positive. When the fourth controllable valve V4 is turned on, the second capacitor C2 discharges to the fourth inductor L4 through the fourth controllable valve V4. When the second capacitor C2 discharges, a negative current passes through the fourth controllable valve V4, and a positive current is cut off by the fourth controllable valve V4. Then, the electric energy generated by the current passing through is stored in the fourth inductor L4, and then the fourth inductor L4 charges the second capacitor C2. The second capacitor C2 and the fourth inductor L4 form a resonant circuit, and the voltage polarity on the second capacitor C2 is negative.

[0089] In this embodiment, by setting the voltage polarity reversal unit 23, the active reversal adjustment of the voltage polarity on the second capacitor C2 can be achieved. The voltage polarity of the second capacitor C2 can be actively adjusted according to the actual working conditions to be simulated to simulate more realistic working conditions.

[0090] In one embodiment, please continue to refer to Figure 3, the phase-changing unit 25 includes: a fifth controllable valve V5 and a sixth controllable valve V6, the positive electrode of the fifth controllable valve V5 is respectively connected to the negative electrode of the sixth controllable valve V6 and the first end of the second capacitor C2, and the negative electrode of the fifth controllable valve V5 is respectively connected to the positive electrode of the sixth controllable valve V6 and the first end of the third inductor L3.

[0091] Among them, the fifth controllable valve V5 and the sixth controllable valve V6 are used for time-sharing conduction to adjust the polarity of the voltage applied to the controllable phase-changing valve 50. When the fifth controllable valve V5 is turned on, the second capacitor C2 discharges to the third inductor L3 through the fifth controllable valve V5. When the second capacitor C2 is discharged, the positive current passes through the fifth controllable valve V5, and the negative current is cut off by the fifth controllable valve V5. Then the electric energy generated by the current passing through is stored in the third inductor L3, and then the third inductor L3 discharges the controllable phase-changing valve 50. The voltage polarity on the controllable phase-changing valve 50 is positive. When the sixth controllable valve V6 is turned on, the second capacitor C2 discharges to the controllable phase-changing valve 50 through the sixth controllable valve V6. When the second capacitor C2 is discharged, the negative current passes through the sixth controllable valve V6, and the positive current is cut off by the sixth controllable valve V6. The voltage polarity on the controllable phase-changing valve 50 is negative.

[0092] In this embodiment, by setting the phase-changing unit 25, the voltage polarity of the controllable phase-changing valve 50 can be adjusted. According to the actual working conditions to be simulated, the voltage polarity applied to the controllable phase-changing valve 50 can be actively adjusted to simulate a more realistic working condition.

[0093] In one embodiment, as shown in FIG4 , the current source circuit 10 includes a power supply 11 and a rectifier-inverter circuit 12. The rectifier-inverter circuit 12 is connected to the power supply 11 and the controllable phase-changing valve 50, respectively. Exemplarily, the power supply 11 is a generator. The rectifier-inverter circuit 12 is used to, under the power supply of the power supply 11, be equivalent to the current stress of the controllable phase-changing valve 50, and output a current waveform according to the power frequency cycle, so as to test the controllable phase-changing valve 50.

[0094] Exemplarily, the rectifier-inverter circuit 12 includes a first three-phase full-bridge rectifier circuit 121, a second three-phase full-bridge rectifier circuit 122, and a smoothing reactor L0. Exemplarily, the first three-phase full-bridge rectifier circuit 121 includes six switch valves (K7-K12) to form a three-phase full-bridge bridge arm; the second three-phase full-bridge rectifier circuit 122 includes six switch valves (K1-K6) to form another three-phase full-bridge bridge arm. The positive electrodes of the switch valves K1, K3, and K5 are respectively connected to the first end of the smoothing reactor L0, the negative electrodes of the switch valves K1, K3, and K5 and the positive electrodes of the switch valves K2, K4, and K6 are respectively connected to the first end of the power supply 11 through the converter transformer, the negative electrodes of the switch valves K2, K4, and K6 and the positive electrodes of the switch valves K7, K9, and K11 are respectively grounded, the negative electrodes of the switch valves K7, K9, and K11 and the positive electrodes of the switch valves K8, K10, and K12 are respectively connected to the second end of the power supply 11 through the converter transformer, and the negative electrodes of the switch valves K8, K10, and K12 are respectively connected to the second end of the smoothing reactor L0. The smoothing reactor L0 is used to keep the DC flowing through stable.

[0095] The controllable phase-changing valve 50 can be connected in parallel with the lower bridge arm of any phase in the first three-phase full-bridge rectifier circuit 121 or the second three-phase full-bridge rectifier circuit 122. For example, in FIG4 , the controllable phase-changing valve 50 is connected in parallel with the lower bridge arm of the third phase of the second three-phase full-bridge rectifier circuit 122, that is, the positive electrode of the controllable phase-changing valve 50 is connected to the negative electrode of the switch valve K5 and the positive electrode of the switch valve K6, respectively, and the negative electrode of the controllable phase-changing valve 50 is grounded, wherein the controllable phase-changing valve 50 is connected in parallel with the switch valve K6. For the convenience of description, the bridge arm connected to the controllable phase-changing valve 50 is called a test bridge arm.

[0096] It should be noted that the current source circuit 10 can operate independently, that is, the current source circuit 10 can operate normally when the controllable phase-changing valve 50 is not connected. In the process of connecting the controllable phase-changing valve 50 for testing, the test bridge arm (such as the switch valve K5 and the switch valve K6 in Figure 4) is locked and the controllable phase-changing valve 50 on the test branch is triggered. The rectifier-inverter drag circuit 12 can be equivalent to the current stress of the controllable phase-changing valve 50 under the power supply of the power supply 11, that is, the controllable phase-changing valve 50 is simulated to be in a normal conduction state, and the current waveform is output according to the power frequency cycle to test the controllable phase-changing valve 50.

[0097] In one embodiment, please continue to refer to FIG4 , the test device of the controllable phase-changing valve further includes an isolation valve Vs. The isolation valve Vs is connected to the rectifier-inverter pair circuit 12 and the controllable phase-changing valve 50 respectively, and the isolation valve Vs is used to isolate the rectifier-inverter pair circuit 12 from the controllable phase-changing valve 50.

[0098] For example, in Fig. 4, the positive electrode of the isolation valve Vs is respectively connected to the negative electrode of the switch valve K5 and the positive electrode of the switch valve K6 in the rectifier-inverter drag circuit 12, and the negative electrode of the isolation valve Vs is connected to the positive electrode of the controllable phase-changing valve 50. In this way, by setting the isolation valve Vs, not only can the passage between the rectifier-inverter drag circuit 12 and the controllable phase-changing valve 50 be controlled to be turned on or off, but also the high voltage and low voltage in the test device can be isolated, thereby improving the controllability, stability and safety of the test device.

[0099] The isolation valve Vs includes a reverse-resistance type integrated gate commutated thyristor (IGCT) device.

[0100] The isolation valve Vs may include a plurality of reverse resistance IGCT devices connected in series, so that the reverse recovery time of the isolation valve Vs can be controlled within 50 μs, and the circuit can achieve a minimum 1-2° turn-off angle, thereby achieving more precise control of the on-state current flowing through the controllable phase-changing valve 50.

[0101] Among them, when the isolation valve Vs is turned on, the test bridge arm of the rectifier-inverter drag circuit 12 is turned on, and the rectifier-inverter drag circuit 12 provides an on-state current (for example, 1000A~7000A) to the controllable phase-changing valve 50, so that the controllable phase-changing valve 50 is turned on, and it can be turned on according to a preset conduction rule (for example, within a power frequency cycle (20ms), at least one-third of the time (6.67ms)), thereby simulating the normal conduction condition of the controllable phase-changing valve 50. When the isolation valve Vs is turned off, it can isolate the current source circuit 10 from the voltage source circuit 20, and isolate the current source circuit 10 from the active shutdown circuit 30, so as to prevent the voltage on the voltage source circuit 20 and the active shutdown circuit 30 from damaging the current source circuit 10.

[0102] In this embodiment, by providing the isolation valve Vs, the on-state current on the controllable phase-changing valve 50 can be accurately controlled, and the current source circuit 10 can also be protected, thereby improving the accuracy and safety of the test.

[0103] In one embodiment, please continue to refer to FIG. 4 , and the active shutdown test condition of the present application will be described in conjunction with FIG. 4 .

[0104] The active shutdown test condition includes a first conduction phase, an active shutdown phase, and a first commutation phase.

[0105] The processing module 40 controls the current source circuit 10 to provide an on-state current to the controllable phase-changing valve 50 , and controls the active shut-off circuit 30 to provide a shut-off test current to the controllable phase-changing valve 50 , so as to simulate the first conduction stage.

[0106] The controllable phase-changing valve 50 is actively closed, and the active closing circuit 30 provides a support voltage for the controllable phase-changing valve 50 to simulate the active closing stage.

[0107] The processing module 40 controls the voltage source circuit 20 to provide a switching voltage for the controllable switching valve 50 to simulate the first switching stage.

[0108] Specifically, the entire process of the active shutdown test condition is described, and reference may be made to the waveform diagram shown in FIG5 . In the entire process of the active shutdown test condition:

[0109] In the first conduction stage, the isolation valve Vs is opened, and the current source circuit 10 provides the on-state current for the controllable phase-changing valve 50, and the controllable phase-changing valve 50 is turned on. Then the on-state current decreases. When the on-state current decreases but has not yet dropped to 0, the first controllable valve V1 in the active shutdown circuit 30 is turned on, and the first capacitor C1 discharges to the controllable phase-changing valve 50 through the first inductor L1 and the second inductor L2 (wherein, the first capacitor C1 has been pre-charged before the first controllable valve V1 is turned on, specifically, the first DC power supply 31 pre-charges the first capacitor C1), and provides a shutdown test current. The current flowing through the controllable phase-changing valve 50 gradually increases until the amplitude of the shutdown test current reaches the first set value. At this time, the controllable phase-changing valve 50 is controlled to be actively shut down, the first controllable valve V1 is shut down, and the first stage ends.

[0110] In the active shutdown stage, after the controllable phase-changing valve 50 is actively shut down, due to the existence of the first inductor L1, the shutdown test current does not immediately become 0, but gradually decreases. In this process, the overcharge current provided by the first inductor L1 charges the third capacitor C3, and a positive support voltage is provided to the controllable phase-changing valve 50 through the third capacitor C3, so that the controllable phase-changing valve 50 is reversely recovered. Until the current provided by the first inductor L1 is consumed, the reverse recovery of the controllable phase-changing valve 50 ends. Then, due to the existence of the support voltage on the third capacitor C3, the controllable phase-changing valve 50 is subjected to the positive voltage, and there is no current on the controllable phase-changing valve 50, and the second stage ends.

[0111] In the first phase-changing stage, the sixth controllable valve V6 is turned on, and the support voltage stored on the third capacitor C3 is discharged to the second capacitor C2 through the sixth controllable valve V6. The voltage on the controllable phase-changing valve 50 gradually decreases until the voltage on the controllable phase-changing valve 50 drops to 0. Then the fourth controllable valve V4 is controlled to be turned on and the third controllable valve V3 is closed. The second capacitor C2 and the fourth inductor L4 form a resonant circuit, and resonance occurs. The resonant circuit charges the second capacitor C2, so that the polarity of the second capacitor C2 is reversed (from positive to negative), the voltage on the second capacitor C2 is a negative voltage, and the voltage on the controllable phase-changing valve 50 is a gradually increasing negative voltage. Then the third controllable valve V3 is turned on, and the fourth controllable valve V4 is closed, and the second capacitor C2 is charged, so that the polarity of the second capacitor C2 is reversed again (from negative to positive). Then the second controllable valve V2 is controlled to be turned on, and the second DC power supply 21 pre-charges and replenishes the second capacitor C2. After the second capacitor C2 is replenished, the third stage ends. At the end of the third stage, the fifth controllable valve V5 is turned off, and the connection between the voltage source circuit 20 and the controllable phase-changing valve 50 is cut off. Next, the working process of the first stage can be repeated to enter the next cycle.

[0112] Among them, it can be seen from the above-mentioned first phase-changing stage that by designing the fourth controllable valve V4, the voltage polarity on the second capacitor C2 can be actively reversed, so that the voltage polarity on the second capacitor C2 can be consistent with the actual working condition. Since there is no active shut-off stage in the actual operation of the controllable phase-changing valve 50, and in the active shut-off stage, the third capacitor C3 provides a positive support voltage for the controllable phase-changing valve 50, so that the second capacitor C2 that would have discharged is not discharged, which is inconsistent with the actual working condition, so it is necessary to design the fourth controllable valve V4 to make the voltage polarity on the second capacitor C2 actively reversed, so that the voltage polarity on the second capacitor C2 is consistent with the actual working condition, and a more realistic actual working condition is simulated for the controllable phase-changing valve 50.

[0113] The process of the phase switching disconnection test condition is described below. Please refer to the waveform diagram of FIG6 . During the phase switching disconnection test condition:

[0114] In the second conduction stage, the isolation valve Vs is opened, and the current source circuit 10 provides the on-state current for the controllable phase-changing valve 50, and the controllable phase-changing valve 50 is turned on. Then the on-state current decreases. When the on-state current decreases but has not yet dropped to 0, the fifth controllable valve V5 in the voltage source circuit 20 is turned on, and the second capacitor C2 discharges to the controllable phase-changing valve 50 through the third inductor L3 (wherein, the second capacitor C2 has been pre-charged before the fifth controllable valve V5 is turned on, specifically, the second controllable valve V2 is turned on, and the second DC power supply 21 pre-charges the second capacitor C2) (the voltage on the second capacitor C2 at this time is defined as a positive voltage), and a sinusoidal current is generated on the controllable phase-changing valve 50. When the sinusoidal current passes 0, the sixth controllable valve V6 is turned on, and the current direction changes at this time, and the controllable phase-changing valve 50 is switched off, and the first stage ends. In the first stage, since the controllable phase-changing valve 50 is in the on state, the voltage on the controllable phase-changing valve 50 is very small.

[0115] In the switching off stage, after the sinusoidal current passes through 0, the polarity on the second capacitor C2 is reversed (from positive to negative). At this time, the sixth controllable valve V6 is turned on, and the second capacitor C2 continues to provide a reverse sinusoidal current to the controllable phase-changing valve 50. There is a reverse recovery voltage on the controllable phase-changing valve 50, so that the controllable phase-changing valve 50 recovers in reverse. When the reverse sinusoidal current is 0, the reverse recovery of the controllable phase-changing valve 50 ends, the controllable phase-changing valve 50 is subjected to the reverse voltage, and there is no current on the controllable phase-changing valve 50, and the second stage ends.

[0116] In the second phase-changing stage, the third controllable valve V3 is turned on, and the second capacitor C2 and the fourth inductor L4 form a resonant circuit, which resonates. The resonant circuit charges the second capacitor C2, so that the polarity of the second capacitor C2 is reversed again (from negative to positive), and then the second capacitor C2 provides a positive voltage to the controllable phase-changing valve 50, so that the voltage on the controllable phase-changing valve 50 is reversed from a negative voltage to a positive voltage. The voltage on the controllable phase-changing valve 50 is reversed, and then the second controllable valve V2 is controlled to be turned on, and the second DC power supply 21 pre-charges and replenishes the energy of the second capacitor C2. After the energy replenishment of the second capacitor C2 is completed, the third stage ends. At the end of the third stage, the fifth controllable valve V5 is turned off, and the connection between the voltage source circuit 20 and the controllable phase-changing valve 50 is cut off. Next, the work flow of the first stage can be repeated to enter the next cycle.

[0117] In this embodiment, a complete test process for an active shutdown test condition and a complete test process for a phase-changing shutdown test condition are provided. By using the test device of the present application, the active shutdown test condition and the phase-changing shutdown test condition can be simulated for the controllable phase-changing valve 50, thereby realizing the test experiment for the controllable phase-changing valve 50.

[0118] In one embodiment, as shown in FIG7 , the test device for the phase-changing valve further includes: an impulse voltage circuit 60. The impulse voltage circuit 60 is connected to the controllable phase-changing valve 50 and is used to provide an impulse voltage for the controllable phase-changing valve 50.

[0119] The impulse voltage circuit 60 includes: an impulse generator 61 and an impulse test switch S. A ball gap is provided between the first end of the impulse generator 61 and the first end of the impulse test switch S, the second end of the impulse generator 61 is connected to the negative electrode of the controllable phase-changing valve 50, and the second end of the impulse test switch S is connected to the positive electrode of the controllable phase-changing valve 50.

[0120] Among them, the impulse generator 61 can provide a voltage impulse for the controllable phase-changing valve 50 in the transient forward voltage test during the recovery period of the controllable phase-changing valve 50.

[0121] Exemplarily, the impulse generator 61 can also be used to perform impulse voltage tests of lightning impulse voltage full wave, lightning impulse voltage chopped wave and operating impulse voltage wave on test items such as power equipment to test their insulation performance.

[0122] Among them, the ball gap is an air gap with a slightly uneven electric field formed by a pair of metal ball electrodes of the same diameter. It is mainly used to measure the peak value of high voltage and can also be used as a protective gap.

[0123] In this embodiment, by setting up an impulse voltage circuit 60, an impulse voltage can be provided to both ends of the controllable phase-changing valve 50, so as to test the controllable phase-changing valve 50 and check whether the reliability of the controllable phase-changing valve 50 meets the standard when subjected to the impulse voltage.

[0124] In one embodiment, as shown in FIG8 , the test device for the phase-changing valve further includes: a fault current circuit 70. The fault current circuit 70 is connected to the controllable phase-changing valve 50 and is used to provide a fault current for the controllable phase-changing valve 50.

[0125] The fault current circuit 70 includes: a fault power supply 71, a fourth capacitor C4, a fifth inductor L5, and a seventh controllable valve V7, wherein the fault power supply 71 is connected in parallel with the fourth capacitor C4, the first end of the fifth inductor L5 is connected to the first end of the fourth capacitor C4, the second end of the fifth inductor L5 is connected to the positive electrode of the seventh controllable valve V7, the negative electrode of the seventh controllable valve V7 is connected to the positive electrode of the controllable phase-changing valve 50, and the second end of the fourth capacitor C4 is connected to the negative electrode of the controllable phase-changing valve 50.

[0126] The fault power supply 71 is used to simulate and output various fault currents. The fault current circuit 70 is powered by a low-voltage large-capacity capacitor and outputs a half-wave sinusoidal current with an amplitude of generally 30kA~60kA and a pulse width of 16~20ms.

[0127] Among them, the fault current can be any abnormal current. For example, a short circuit is a fault where the live wire touches the neutral wire or the ground wire. If the circuit is interrupted by a fault in the current-carrying wire (phase wire or neutral wire) or a fuse or circuit breaker blows, an open circuit fault occurs, and a fault current is generated in the circuit. In a three-phase system, the fault may involve one or more phases and grounding, or it may occur only between phases. In a "ground fault" or "ground fault", the current flows into the ground and a fault current is generated in the circuit.

[0128] In this embodiment, by setting up the fault current circuit 70, a fault current can be provided to the controllable phase-changing valve 50, so as to test the controllable phase-changing valve 50 and verify whether the reliability of the controllable phase-changing valve 50 meets the standard when the fault current occurs.

[0129] In one embodiment, as shown in FIG. 9 , a method for testing a controllable phase-changing valve is provided. The method is applied to the testing device for the controllable phase-changing valve in the above embodiment. The method includes steps S900 - S930 .

[0130] Step S900, respectively controlling the working states of the current source circuit and the voltage source circuit to simulate a switching disconnection test condition for the controllable phase-changing valve.

[0131] Step S910, respectively controlling the working states of the current source circuit, the voltage source circuit, and the active shutdown test circuit, and controlling the controllable phase-changing valve to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable phase-changing valve.

[0132] Step S920, obtaining electrical parameters of the controllable phase-changing valve under target test conditions.

[0133] The target test condition includes at least one of an active shutdown test condition and a phase switching shutdown test condition.

[0134] Step S930, determining the test result of the controllable phase-changing valve based on the electrical parameters.

[0135] In this embodiment, the working states of the current source circuit, the voltage source circuit, and the active shut-off circuit are controlled respectively to simulate the target test condition for the controllable phase-changing valve, that is, the current source circuit and the voltage source circuit can be used in combination to simulate the phase-changing shut-off test condition for the controllable phase-changing valve, and then collect the electrical parameters of the controllable phase-changing valve under the phase-changing shut-off test condition, and the current source circuit, the voltage source circuit, and the active shut-off circuit can be used in combination to simulate the active shut-off test condition for the controllable phase-changing valve, so as to facilitate the collection of the electrical parameters of the controllable phase-changing valve under the active shut-off test condition. It is convenient to determine the test result of the controllable phase-changing valve through the collected electrical parameters, and then judge the performance and reliability of the controllable phase-changing valve, so as to realize the test of the controllable phase-changing valve.

[0136] In one embodiment, as shown in FIG10 , step S910 controls the working states of the current source circuit, the voltage source circuit, and the active shutdown test circuit respectively, and controls the controllable phase-changing valve to be actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable phase-changing valve. It includes steps S1000-S1020.

[0137] Step S1000, controlling the current source circuit to provide on-state current for the controllable phase-switching valve, controlling the active shutdown circuit to provide a shutdown test current for the controllable phase-switching valve, and controlling the controllable phase-switching valve to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate a first conduction stage.

[0138] Step S1010: The active shutdown circuit provides a support voltage for the controllable phase-changing valve to simulate an active shutdown stage.

[0139] Step S1020, controlling the voltage source circuit to provide a switching voltage for the controllable switching valve to simulate a first switching stage.

[0140] In this embodiment, a test method under an active shutdown test condition is provided, which can simulate an active shutdown test condition for a controllable phase-changing valve and verify the performance and reliability of the controllable phase-changing valve under the active shutdown test condition.

[0141] It should be understood that, although the various steps in the flowcharts of Figures 9 and 10 are displayed in sequence according to the indications of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless there is a clear description in this article, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a part of the steps in Figures 9 and 10 may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0142] Those of ordinary skill in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), tape, floppy disk, flash memory or optical memory, etc. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM).

[0143] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", "ideal embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

[0144] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0145] The above-mentioned embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the attached claims.

Claims

1. A test device for a controllable phase-changing flow control valve, characterized in that: The device comprises: a current source circuit connected to the controllable phase-changing valve, and used for providing an on-state current to the controllable phase-changing valve when the controllable phase-changing valve is in an on state; a voltage source circuit connected to the controllable phase-changing valve, and used for providing a phase-changing voltage to the controllable phase-changing valve when the controllable phase-changing valve is in an off state; An active shut-off circuit, connected to the controllable phase-changing valve, for providing a shut-off test current for the controllable phase-changing valve when the controllable phase-changing valve is in a conducting state; A processing module is respectively connected to the current source circuit, the voltage source circuit, the active shutdown circuit, and the controllable phase-changing valve, and is used to respectively control the working states of the current source circuit, the voltage source circuit, and the active shutdown circuit, simulate a target test condition for the controllable phase-changing valve, and collect electrical parameters of the controllable phase-changing valve under the target test condition, wherein the electrical parameters are used to determine the test results of the controllable phase-changing valve, and the target test condition includes at least one of an active shutdown test condition and a phase-changing shutdown test condition.

2. The test device for a controllable phase-changing valve according to claim 1, characterized in that: The active shutdown circuit includes: a first DC power supply, a first energy storage unit, a first switch unit, and a first discharge output unit, wherein: The first DC power supply is connected in parallel with the first energy storage unit, and is used to charge the first energy storage unit; The first energy storage unit is used to store electrical energy; The first switch unit is arranged in series between the positive electrode of the controllable phase-changing valve and the first energy storage unit, and is used to control the conduction or disconnection of the passage between the positive electrode of the controllable phase-changing valve and the first energy storage unit; The first discharge output unit is arranged in series between the positive electrode of the controllable phase-changing valve and the first energy storage unit, so that the first energy storage unit provides a stable shut-off test current for the controllable phase-changing valve.

3. The test device for a controllable phase-changing valve according to claim 2, characterized in that: The first energy storage unit includes a first capacitor, the first switch unit includes a first controllable valve, and the first discharge output unit includes a first inductor, a second inductor and a freewheeling diode. The first capacitor is connected in parallel with the first DC power supply, the positive electrode of the first controllable valve is connected to the first end of the first capacitor, the negative electrode of the first controllable valve is connected to the first end of the first inductor, the second end of the first inductor is connected to the positive electrode of the controllable phase-changing valve, the second end of the first capacitor is connected to the negative electrode of the controllable phase-changing valve, the second inductor is connected in series between the positive electrode of the first controllable valve and the first end of the first capacitor, the positive electrode of the freewheeling diode is connected to the positive electrode of the first controllable valve, and the negative electrode of the freewheeling diode is connected to the first end of the first capacitor, wherein: The first controllable valve is used to be turned on during the process of testing the active shut-off performance of the controllable phase-changing valve, so that the first capacitor discharges to the controllable phase-changing valve through the first inductor to provide the shut-off test current; The controllable phase-changing valve is used to actively shut down when the amplitude of the shut-off test current reaches a first set value.

4. The test device for a controllable phase-changing valve according to claim 1, characterized in that: The active shutdown test condition includes a first conduction phase, an active shutdown phase, and a first commutation phase; The processing module controls the current source circuit to provide an on-state current for the controllable phase-changing valve, and controls the active shut-off circuit to provide a shut-off test current for the controllable phase-changing valve, so as to simulate the first conduction stage; The controllable phase-changing valve is actively shut down, and the active shut-down circuit provides a support voltage for the controllable phase-changing valve to simulate the active shut-down stage; The processing module controls the voltage source circuit to provide a switching voltage for the controllable switching valve to simulate the first switching stage.

5. The test device for a controllable phase-changing flow control valve according to claim 1, characterized in that: The voltage source circuit includes: a second DC power supply, a second switch unit, a voltage polarity reversal unit, a second energy storage unit, a phase change unit, a second discharge output unit, and a third energy storage unit. The positive electrode of the second DC power supply is connected to the first end of the second switch unit, the second end of the second switch unit is connected to the first end of the voltage polarity reversal unit, the negative electrode of the second DC power supply is respectively connected to the second end of the voltage polarity reversal unit and the negative electrode of the controllable phase-changing valve, the second energy storage unit is connected in parallel with the voltage polarity reversal unit, the phase change unit is connected in series between the second energy storage unit and the positive electrode of the controllable phase-changing valve, the second discharge output unit is connected in series between the second energy storage unit and the positive electrode of the controllable phase-changing valve, and the third energy storage unit is connected in parallel with the controllable phase-changing valve; wherein, The voltage polarity reversal unit is used to adjust the polarity of the voltage on the second energy storage unit; The phase-changing unit is used to adjust the polarity of the voltage applied to the controllable phase-changing valve.

6. The test device for a controllable phase-changing valve according to claim 5, characterized in that: The second switch unit includes a second controllable valve, the second energy storage unit includes a second capacitor, the third energy storage unit includes a third capacitor, and the second discharge output unit includes a third inductor. The positive electrode of the second DC power supply is connected to the positive electrode of the second controllable valve, the negative electrode of the second controllable valve is connected to the first end of the voltage polarity reversal unit, the negative electrode of the second DC power supply is respectively connected to the second end of the voltage polarity reversal unit and the negative electrode of the controllable phase-changing valve, the second capacitor is connected in parallel with the voltage polarity reversal unit, the first end of the phase-changing unit is connected to the first end of the second capacitor, the second end of the phase-changing unit is connected to the first end of the third inductor, the second end of the third inductor is connected to the positive electrode of the controllable phase-changing valve, and the third capacitor is connected in parallel with the controllable phase-changing valve.

7. The test device for a controllable phase-changing valve according to claim 6, characterized in that: The voltage polarity reversal unit includes: a fourth inductor, a third controllable valve, and a fourth controllable valve, wherein the first end of the fourth inductor is connected to the negative electrode of the second controllable valve, the second end of the fourth inductor is respectively connected to the first end of the phase switching unit and the first end of the second capacitor, the second end of the second capacitor is connected to the negative electrode of the second DC power supply, the positive electrode of the third controllable valve is respectively connected to the negative electrode of the fourth controllable valve and the negative electrode of the second DC power supply, and the negative electrode of the third controllable valve is respectively connected to the positive electrode of the fourth controllable valve and the first end of the fourth inductor; The third controllable valve and the fourth controllable valve are used for conducting in a time-sharing manner to adjust the polarity of the voltage on the second capacitor.

8. The test device for a controllable phase-changing valve according to claim 6, characterized in that: The phase-changing unit comprises: a fifth controllable valve and a sixth controllable valve, wherein the positive electrode of the fifth controllable valve is respectively connected to the negative electrode of the sixth controllable valve and the first end of the second capacitor, and the negative electrode of the fifth controllable valve is respectively connected to the positive electrode of the sixth controllable valve and the first end of the third inductor; The fifth controllable valve and the sixth controllable valve are used for time-sharing conduction to adjust the polarity of the voltage applied to the controllable phase-changing valve.

9. The test device for a controllable phase-changing valve according to claim 1, characterized in that: The current source circuit includes: a power supply and a rectifier-inverter circuit, the rectifier-inverter circuit is connected to the power supply and the controllable phase-changing valve respectively, and the rectifier-inverter circuit is used to be equivalent to the current stress of the controllable phase-changing valve under the power supply of the power supply.

10. The test device for a controllable phase-changing valve according to claim 9, characterized in that: The device also includes an isolation valve, which is connected to the rectifier-inverter pair circuit and the controllable phase-changing valve respectively, and is used to isolate the rectifier-inverter pair circuit from the controllable phase-changing valve.

11. The test device for a controllable phase-changing valve according to claim 10, characterized in that: The isolation valve comprises a reverse-blocking integrated gate-commutated thyristor.

12. The test device for a controllable phase-changing valve according to any one of claims 1 to 11, characterized in that: The test device of the controllable phase-changing flow control valve further comprises: The impulse voltage circuit is connected to the controllable phase-changing valve and is used to provide an impulse voltage for the controllable phase-changing valve.

13. The test device for a controllable phase-changing valve according to claim 12, characterized in that: The impulse voltage circuit includes: an impulse generator and an impulse test switch, a spherical gap is provided between the first end of the impulse generator and the first end of the impulse test switch, the second end of the impulse generator is connected to the negative pole of the controllable phase-changing valve, and the second end of the impulse test switch is connected to the positive pole of the controllable phase-changing valve.

14. The test device for a controllable phase-changing valve according to any one of claims 1 to 11, characterized in that: The test device of the controllable phase-changing flow control valve further comprises: The fault current circuit is connected to the controllable phase-changing valve and is used to provide a fault current for the controllable phase-changing valve.

15. The test device for a controllable phase-changing valve according to claim 14, characterized in that: The fault current circuit includes: a fault power supply, a fourth capacitor, a fifth inductor, and a seventh controllable valve. The fault power supply is connected in parallel with the fourth capacitor, the first end of the fifth inductor is connected to the first end of the fourth capacitor, the second end of the fifth inductor is connected to the positive electrode of the seventh controllable valve, the negative electrode of the seventh controllable valve is connected to the positive electrode of the controllable phase-changing valve, and the second end of the fourth capacitor is connected to the negative electrode of the controllable phase-changing valve.

16. A method for testing a controllable phase-changing flow control valve, characterized in that: The method is applied to a test device for a controllable phase-changing valve according to any one of claims 1 to 15, and the method comprises: Controlling the working states of the current source circuit and the voltage source circuit respectively, and simulating a switching disconnection test condition for the controllable phase-changing valve; Respectively controlling the working states of the current source circuit, the voltage source circuit, and the active shutdown circuit, and controlling the controllable phase-changing valve to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable phase-changing valve; Acquiring electrical parameters of the controllable phase-changing valve under a target test condition, wherein the target test condition includes at least one of an active shut-off test condition and a phase-changing shut-off test condition; A test result of the controllable phase-changing valve is determined based on the electrical parameters.

17. The method for testing a controllable phase-changing valve according to claim 16, characterized in that: The active shutdown test condition includes a first conduction stage, an active shutdown stage, and a first commutation stage; the operating states of the current source circuit, the voltage source circuit, and the active shutdown circuit are controlled respectively, and the controllable commutation valve is controlled to actively shut down when the amplitude of the shutdown test current reaches a first set value, so as to simulate an active shutdown test condition for the controllable commutation valve, including: Controlling the current source circuit to provide an on-state current for the controllable phase-changing valve, controlling the active shut-off circuit to provide a shut-off test current for the controllable phase-changing valve, and controlling the controllable phase-changing valve to actively shut down when the amplitude of the shut-off test current reaches a first set value, so as to simulate the first conduction stage; The controllable phase-changing valve is actively shut down, and the active shut-down circuit provides a support voltage for the controllable phase-changing valve to simulate the active shut-down stage; The voltage source circuit is controlled to provide a switching voltage for the controllable switching valve to simulate the first switching stage.

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