Test platform and test method, electronic device

Abstract

This application relates to a test platform and test method, and electronic equipment. The test platform includes: a power supply module providing an initial voltage; an energy storage module outputting a test voltage based on the initial voltage, wherein the test voltage is greater than the initial voltage; a load module for exchanging reactive power with the energy storage element in the energy storage module to form a load current; a data acquisition module for acquiring test signals; and a control module for controlling the power supply module to output the initial voltage to the energy storage module, controlling the energy storage module to output the test voltage based on the initial voltage, and controlling the H-bridge topology to perform polarity reversal processing on the test voltage to form a load current on the load module. The control module is also used to acquire the test signal through the data acquisition module and determine the test result based on the test signal. This application eliminates the need for a high-voltage DC power supply and a high-power active load, reducing test costs.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to a test platform and test method, and electronic equipment. Background Technology

[0002] Active commutation valves, which consist of multiple IGCT (Integrated Gate Commutated Thyristor) devices connected in series, are the core technology for realizing high-voltage, high-capacity applications of IGCTs and have become a research hotspot in the field of power electronics. Before practical engineering applications, IGCT series valves must undergo comprehensive testing to verify their electrical and thermal stress characteristics under various operating conditions to ensure safe and reliable operation.

[0003] However, there is still a lack of high-voltage and high-current testing methods for IGCT series valves in related technologies. Traditional high-voltage testing methods usually require a high-voltage DC power supply with a voltage equivalent to the rated voltage of the IGCT series valve under test as the input, and a high-power active load is required to simulate the actual operating current.

[0004] On the one hand, the high cost, large size, and long construction period of high-voltage DC power supplies lead to high construction costs for test platforms for IGCT series valves; on the other hand, the energy consumption of high-power active loads is huge, requiring a large amount of electrical energy to be consumed during the test, further increasing the test cost.

[0005] It is evident that the high-pressure, high-current testing methods for IGCT series valves in the relevant technologies suffer from the technical problem of high testing costs. Summary of the Invention

[0006] Therefore, it is necessary to provide a test platform, test method, and electronic equipment to address the above-mentioned technical problems, so as to achieve high-pressure and high-current testing of IGCT series valves at a lower test cost.

[0007] Firstly, this application provides a testing platform.

[0008] The test platform is used to test the first IGCT series valve and / or the second IGCT series valve in the H-bridge topology; the test platform includes:

[0009] The power module is used to provide the initial voltage;

[0010] An energy storage module, wherein the input terminal of the energy storage module is connected to the output terminal of the power supply module, and the output terminal of the energy storage module is used to connect to the DC input terminal of the H-bridge topology;

[0011] The load module is used to connect to the AC output terminal of the H-bridge topology and to exchange reactive power with the energy storage element in the energy storage module to form a load current.

[0012] The acquisition module is used to connect to the test signal output terminal of the H-bridge topology and to acquire the test signal of the first IGCT series valve and / or the test signal of the second IGCT series valve when the load current is generated.

[0013] A control module is connected to the power supply module, the energy storage module, and the acquisition module, and is used to connect to the H-bridge topology. The control module controls the power supply module to output the initial voltage to the energy storage module, controls the energy storage module to output a test voltage based on the initial voltage, the test voltage being greater than the initial voltage, and controls the H-bridge topology to perform polarity reversal processing on the test voltage to form the load current on the load module. The control module is also used to acquire test signals through the acquisition module to determine the test results of the first IGCT series valve and / or the second IGCT series valve.

[0014] In one embodiment, the energy storage module includes multiple switched capacitor units, which are connected to the power module. The multiple switched capacitor units are connected in series to form a cascade chain of switched capacitor units, and the cascade chain of switched capacitor units is connected in parallel with the H-bridge topology.

[0015] The control module is also used to control the power module to charge each of the switched capacitor units respectively, so as to charge all the switched capacitor units to a preset voltage.

[0016] In one embodiment, the switched capacitor unit includes an upper switching transistor, a lower switching transistor, and the energy storage element; a first end of the upper switching transistor is connected to a first end of the energy storage element, a second end of the upper switching transistor is connected to a first end of the lower switching transistor, a second end of the lower switching transistor is connected to a second end of the energy storage element, and the power module is connected to the first end of the upper switching transistor and the second end of the lower switching transistor respectively.

[0017] The control module is also used to control both the upper and lower switching transistors to turn off, so that the power module can charge the energy storage element to the preset voltage.

[0018] In one embodiment, in the cascaded chain of switched capacitor units, the second end of the lower switch transistor in the preceding switched capacitor unit is connected to the first end of the lower switch transistor in the following switched capacitor unit, and the second end of the upper switch transistor in the first switched capacitor unit and the second end of the lower switch transistor in the last switched capacitor unit are both connected to the DC input terminal of the H-bridge topology.

[0019] The control module is also used to control the upper switching transistors in each of the switched capacitor units to turn on in a preset turn-on sequence, and to control the lower switching transistors in each of the switched capacitor units to remain off, so as to charge the H-bridge topology.

[0020] In one embodiment, both the first IGCT series valve and the second IGCT series valve are formed by connecting N IGCT power units in series, where N is an even number greater than or equal to 2, and each of the IGCT power units is connected to the control module.

[0021] The control module is also used to repeat a preset first control process after charging the H-bridge topology to balance the terminal voltage of each IGCT power unit.

[0022] The first control process is as follows: acquiring the terminal voltage of each IGCT power unit; sorting the terminal voltages of each IGCT in descending order to obtain the terminal voltage ranking of each IGCT power unit; controlling the IGCT power unit whose terminal voltage ranking is in the first N / 2 positions to be turned on and maintaining it for a preset time.

[0023] In one embodiment, the control module is further configured to repeat a preset second control process after charging the H-bridge topology, so as to adjust the waveform of the test voltage to a positive polarity sine half-wave.

[0024] The second control process is as follows: acquiring the energy storage element voltage of all the energy storage elements; in the first half of a half-wave cycle, sequentially turning on the upper switching transistors in each of the switched capacitor units and turning off the lower switching transistors in each of the switched capacitor units in order of energy storage element voltage from high to low; in the second half of a half-wave cycle, sequentially turning off the upper switching transistors in each of the switched capacitor units and turning on the lower switching transistors in each of the switched capacitor units in order of energy storage element voltage from high to low.

[0025] In one embodiment, the H-bridge topology has four arms, the first IGCT series valve constitutes the first and second arms of the H-bridge topology, and the second IGCT series valve constitutes the third and fourth arms of the H-bridge topology.

[0026] The control module is also used to output an H-bridge pulse to the H-bridge topology after adjusting the waveform of the test voltage to a positive polarity sine half-wave, so as to control the H-bridge topology to perform polarity reversal processing on the test voltage.

[0027] The H-bridge pulse is used to control the first and fourth arms of the H-bridge topology to be turned on during the first half-wave period, and the second and third arms to be turned off during the first half-wave period; and to control the first and fourth arms of the H-bridge topology to be turned off during the second half-wave period, and the second and third arms to be turned on during the second half-wave period; the second half-wave period is the next adjacent half-wave period of the first half-wave period.

[0028] In one embodiment, the control module is further configured to control the initial voltage output by the power module and / or the on-time ratio of the upper switching transistor in each of the switched capacitor units, so as to adjust the load current.

[0029] Secondly, this application provides a testing method applied to the testing platform described in any of the embodiments of the first aspect above, the testing method comprising:

[0030] The control power module outputs an initial voltage to the energy storage module;

[0031] The energy storage module is controlled to output the test voltage based on the initial voltage;

[0032] The H-bridge topology is controlled to reverse the polarity of the test voltage in order to generate the load current on the load module;

[0033] When the load current is generated on the load module, the test signal of the first IGCT series valve and / or the test signal of the second IGCT series valve are acquired by the acquisition module to determine the test result of the first IGCT series valve and / or the test result of the second IGCT series valve.

[0034] Thirdly, this application provides an electronic device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the test method described in the second aspect above.

[0035] The aforementioned test platform, test methods, and electronic equipment utilize a power supply module to provide an initial voltage, which is then boosted by an energy storage module to output the test voltage. This allows for the construction of a high-voltage test environment using a low-voltage power supply, eliminating the need for a high-voltage DC power supply with a voltage equivalent to the rated voltage of the IGCT series valve under test, thus reducing the construction cost of the test platform. Simultaneously, the H-bridge topology reverses the polarity of the test voltage, allowing reactive power exchange between the load module and the energy storage element in the energy storage module to form the load current. Electrical energy can circulate between the load module and the energy storage element, eliminating the need for additional high-power active loads to consume energy, thereby reducing operating energy consumption during the test. Based on this, the acquisition module acquires the test signal of the IGCT series valve under test when a load current is generated, and the control module determines the test result based on the test signal, achieving effective evaluation of the IGCT series valve. Compared to related technologies, this application can complete the performance verification of the IGCT series valve under high-voltage and high-current conditions at a lower test cost, contributing to reduced testing costs. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the H-bridge topology formed by the first IGCT series valve and the second IGCT series valve;

[0038] Figure 2 This is a schematic diagram of the test platform in one embodiment;

[0039] Figure 3 This is a schematic diagram of the test platform in another embodiment;

[0040] Figure 4 This is a waveform diagram of the test voltage, H-bridge pulse, and voltage on the load module in one embodiment;

[0041] Figure 5 This is a flowchart illustrating a testing method in one embodiment.

[0042] Explanation of reference numerals in the attached figures:

[0043] 100, H-bridge topology; 110, First IGCT series valve; 120, Second IGCT series valve; 130, IGCT power unit; 200, Power module; 210, Power supply equipment; 220, Recharge branch; 300, Energy storage module; 310, Cascaded switched capacitor unit; 311, Switched capacitor unit; 400, Load module; 500, Acquisition module; 600, Control module; 700, Soft start module; QB1, First bridge arm; QB2, Second bridge arm; QB3, Third bridge arm; QB4, Fourth bridge arm; T1, Upper switching transistor; T2, Lower switching transistor; C, Energy storage element; R1, Voltage equalizing resistor; R2, Current limiting resistor; S, Bypass switch. Detailed Implementation

[0044] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings, which illustrate embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that the disclosure of this application will be thorough and complete.

[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0046] It is understood that the terms "first," "second," etc., used herein may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0047] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0048] It is understandable that "at least one" refers to one or more, and "multiple" refers to two or more. "At least a part of an element" refers to part or all of an element.

[0049] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0050] In power electronics applications such as high-voltage direct current (HVDC) transmission, flexible direct current (DC) transmission, and renewable energy grid integration, active commutation valves composed of multiple integrated gate commutator (IGCT) devices connected in series are the core technology for realizing high-voltage, high-capacity IGCT applications. Compared to traditional insulated-gate bipolar transistors (IGBTs), IGCTs offer higher withstand voltage, greater current carrying capacity, lower on-state voltage drop, and higher reliability, demonstrating significant advantages in low-frequency applications such as DC grids and renewable energy integration. They have become a research hotspot in the field of power electronics. However, before practical engineering applications, IGCT series valves must undergo comprehensive testing and verification under rated voltage, rated current, and various overload conditions to verify their electrical and thermal stress characteristics under different operating conditions, thereby ensuring the safety and reliability of the IGCT series valves after they are put into actual operation.

[0051] In related technologies, high-voltage, high-current testing methods for IGCT series valves are still relatively lacking. Traditional high-voltage testing methods typically require a high-voltage DC power supply with a voltage equivalent to the rated voltage of the IGCT series valve under test as the input terminal to provide the test platform with a high-voltage DC bus voltage equivalent to the actual operating conditions. At the same time, a high-power active load is also required to simulate the actual operating current in order to verify the switching characteristics, voltage equalization performance, and heat dissipation capability of the IGCT series valve under load conditions.

[0052] However, high-voltage DC power supplies are expensive, bulky, and have long manufacturing cycles, resulting in high initial construction costs for the test platform. Furthermore, high-power active loads continuously consume large amounts of electrical energy during testing, further increasing the long-term operating costs of the test platform. Therefore, existing high-voltage, high-current testing methods for IGCT series valves suffer from high testing costs.

[0053] Based on this, the embodiments of this application provide a test platform designed to achieve high-pressure, high-current testing of IGCT series valves at a lower testing cost.

[0054] This application provides a testing platform for testing a first IGCT series valve 110 and / or a second IGCT series valve 120. (Refer to...) Figure 1 The first IGCT series valve 110 and the second IGCT series valve 120 are both formed by connecting N IGCT power units 130 in series, where N is an even number greater than or equal to 2. During testing, the first IGCT series valve 110 and the second IGCT series valve 120 are connected to form an H-bridge topology 100. Specifically, the first IGCT series valve 110 and the second IGCT series valve 120 together constitute the four arms of the H-bridge topology 100. For example, the first IGCT series valve 110 constitutes the first arm QB1 and the second arm QB2 of the H-bridge topology 100, and the second IGCT series valve 120 constitutes the third arm QB3 and the fourth arm QB4 of the H-bridge topology 100. The connection points of the first arm QB1 and the second arm QB2, and the connection points of the third arm QB3 and the fourth arm QB4, serve as the two AC output terminals of the H-bridge topology 100 (e.g., ...). Figure 1 Out1 and Out2), the connection point of the first bridge arm QB1 and the third bridge arm QB3, and the connection point of the second bridge arm QB2 and the fourth bridge arm QB4 serve as the two DC input terminals of the H-bridge topology 100 (e.g., Out1 and Out2 in the diagram), are used as the two DC input terminals of the H-bridge topology 100. Figure 1 (In1 and In2 in the text).

[0055] Reference Figure 2 The test platform provided in this application includes a power module 200, an energy storage module 300, a load module 400, a data acquisition module 500, and a control module 600.

[0056] The power module 200 is used to provide the initial voltage.

[0057] For example, the power module 200 can be a power supply device with DC voltage output function, such as an adjustable DC power supply, a switching power supply, a linear regulated power supply, or an AC-DC converter. As an optional implementation, the input terminal of the power module 200 is connected to the mains power. The power module 200 may be equipped with a rectification unit and a voltage regulation unit, which output an adjustable DC voltage in the range of 0 to 3000V after rectification and voltage regulation, thereby providing the initial voltage.

[0058] By setting the power module 200 to an adjustable DC power supply, the initial voltage can be flexibly adjusted according to the needs of different test conditions.

[0059] The input terminal of the energy storage module 300 is connected to the output terminal of the power supply module 200, and the output terminal of the energy storage module 300 is used to connect to the DC input terminal of the H-bridge topology 100. The energy storage module 300 is used to receive the initial voltage provided by the power supply module 200, and outputs a test voltage based on the initial voltage, wherein the test voltage is greater than the initial voltage.

[0060] The energy storage module 300 has a voltage boosting function, which can convert the lower initial voltage provided by the power supply module 200 into a higher test voltage and then output it to the H-bridge topology 100. For example, the energy storage module 300 can be a capacitor array formed by connecting multiple energy storage capacitors in series, or a cascade chain 310 of multiple switched capacitor units 311 connected in series, or other circuit structures with energy storage and voltage superposition functions.

[0061] By setting up an energy storage module 300 to achieve voltage boosting, the test platform only needs to be configured with a power supply module 200 with a lower rated voltage to build a high-voltage test environment, without the need for an expensive high-voltage DC power supply, thus significantly reducing the construction cost of the test platform.

[0062] The load module 400 is used to connect to the AC output terminal of the H-bridge topology 100. The load module 400 is used to exchange reactive power with the energy storage element in the energy storage module 300 to form a load current in the test circuit.

[0063] For example, the load module 400 can employ components with inductive load characteristics, such as AC reactors, inductors, or the equivalent impedance of a transformer. When the H-bridge topology 100 outputs the test voltage to the load module 400 after polarity reversal, periodic energy exchange occurs between the inductor in the load module 400 and the energy storage capacitor in the energy storage module 300. This periodic energy exchange means that during half a cycle, electrical energy is transferred from the energy storage capacitor to the inductor and stored as magnetic field energy; during the other half cycle, the inductor releases magnetic field energy and feeds it back to the energy storage capacitor.

[0064] This reactive power exchange method allows for the generation of a continuous load current in the circuit without the need for additional high-power active loads to consume electrical energy. Therefore, during testing, the primary energy is circulated between the load module 400 and the energy storage module 300. The power module 200 only needs to replenish a small amount of active power, such as switching losses and line losses, in the test circuit to maintain the continuous existence of the load current, thus significantly reducing operating energy consumption and electricity costs during testing.

[0065] The acquisition module 500 is used to connect to the test signal output terminal of the H-bridge topology 100. The acquisition module 500 is used to acquire the test signal of the first IGCT series valve 110 and / or the test signal of the second IGCT series valve 120 when a load current is generated.

[0066] In some embodiments, the test signals include electrical test signals and thermodynamic test signals. The electrical test signals are used to characterize the electrical stress characteristics of the first IGCT series valve 110 and the second IGCT series valve 120, while the thermodynamic test signals are used to characterize the thermal stress characteristics of the first IGCT series valve 110 and the second IGCT series valve 120. Based on the analysis of the electrical and thermodynamic test signals, the first IGCT series valve 110 and the second IGCT series valve 120 are tested.

[0067] In some embodiments, the test signal output terminal of the H-bridge topology 100 refers to the output terminal of any one of the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100 that can output a test signal. For example, when acquiring electrical test signals, the test signal output terminal of the H-bridge topology 100 can be the input terminal, output terminal, or control terminal of the IGCT power unit 130 in the first IGCT series valve 110 and the second IGCT series valve 120. As another example, when acquiring thermodynamic test signals, the test signal output terminal of the H-bridge topology 100 can be any heating location of the IGCT power unit 130 in the first IGCT series valve 110 and the second IGCT series valve 120.

[0068] For example, the acquisition module 500 may include at least one of the sensing elements such as a voltage sensor, a current sensor, a fiber optic thermometer, a thermistor, or a thermocouple. The voltage sensor and current sensor are used to acquire the voltage stress (such as peak voltage and turn-off overvoltage) and current stress (such as peak current and current change rate) experienced by the IGCT series valve during testing. The fiber optic thermometer, thermistor, or thermocouple is used to acquire the temperature changes of the chip or heat sink of the IGCT series valve during operation to evaluate its thermal stress characteristics. The acquisition module 500 transmits the acquired test signals to the control module 600 for subsequent analysis and judgment.

[0069] The control module 600 is connected to the power module 200, the energy storage module 300, and the acquisition module 500, and is also used to connect to the H-bridge topology 100. The control module 600 controls the power module 200 to output an initial voltage to the energy storage module 300, controls the energy storage module 300 to output a test voltage based on the initial voltage, and controls the H-bridge topology 100 to perform polarity reversal processing on the test voltage to generate a load current on the load module 400. The control module 600 is also used to acquire test signals through the acquisition module 500 to determine the test results for the first IGCT series valve 110 and / or the second IGCT series valve 120.

[0070] For example, the control module 600 may be any one or more combinations of valve controllers, industrial controllers, field programmable gate arrays (FPGAs), digital signal processors (DSPs), and microcontrollers (MCUs).

[0071] As an optional implementation, the control module 600 and the energy storage module 300, as well as the control module 600 and the H-bridge topology 100, are connected by optical fiber communication to achieve electrical isolation between high and low voltage and signal transmission that resists electromagnetic interference, ensuring reliable signal transmission under high voltage and high current test environment.

[0072] Under the control of the control module 600, the working process of the test platform is roughly as follows: First, the control module 600 controls the power module 200 to start and outputs an initial voltage to the energy storage module 300, which receives the initial voltage and stores energy. Second, after the energy storage module 300 completes energy storage, the control module 600 controls the energy storage module 300 to output the stored electrical energy to the DC input terminal of the H-bridge topology 100 in the form of a test voltage, wherein the amplitude of the test voltage is greater than the amplitude of the initial voltage, realizing the boost conversion of the initial voltage. Then, the control module 600 controls the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100 to turn on and off according to the set commutation sequence. The DC input test voltage is reversed to convert it into an AC voltage output to the load module 400. Then, the load module 400 exchanges reactive power with the energy storage element in the energy storage module 300, forming a continuous AC load current in the test circuit, thereby enabling the first IGCT series valve 110 and the second IGCT series valve 120 to operate under load. During the formation of the load current, the acquisition module 500 acquires the test signals of the first IGCT series valve 110 and the second IGCT series valve 120 in real time and transmits them to the control module 600. Finally, the control module 600 analyzes and processes the acquired test signals to determine the test results of the first IGCT series valve 110 and the second IGCT series valve 120.

[0073] Based on the test platform provided in this application, the initial voltage provided by the power module 200 is boosted by the energy storage module 300 to output the test voltage. A high-voltage test environment can be constructed using a low-voltage power supply, eliminating the need for a high-voltage DC power supply equivalent to the rated voltage of the IGCT series valve under test, thus reducing the construction cost of the test platform. Simultaneously, the H-bridge topology 100 reverses the polarity of the test voltage, allowing the load module 400 and the energy storage element in the energy storage module 300 to exchange reactive power to form a load current. Electrical energy can circulate between the load module 400 and the energy storage element, eliminating the need for additional high-power active loads to consume energy, thereby reducing operating energy consumption during the test. Furthermore, the acquisition module 500 acquires the test signal of the IGCT series valve under test when a load current is formed, and the control module 600 determines the test result based on the test signal, achieving effective evaluation of the IGCT series valve. Compared to related technologies, this application can complete the performance verification of the IGCT series valve under high-voltage and high-current conditions at a lower test cost, contributing to reduced testing costs.

[0074] In some of these embodiments, reference is made to Figure 3 The energy storage module 300 includes multiple switched capacitor units 311, which are connected to the power module 200. The multiple switched capacitor units 311 are connected in series to form a switched capacitor unit cascade chain 310, which is connected in parallel with the H-bridge topology 100.

[0075] The control module 600 is also used to control the power module 200 to charge each switched capacitor unit 311 respectively, so as to charge all switched capacitor units 311 to a preset voltage.

[0076] The number of switched capacitor units 311 can be flexibly configured according to the voltage level required for actual testing, for example, it can be 2, 3, 4, 5, 6, 8, 10 or more. The specific number of switched capacitor units 311 depends on the magnitude of the initial voltage provided by the power supply module 200 and the target amplitude of the test voltage that the test platform needs to output. The higher the required test voltage, the more switched capacitor units 311 need to be connected in series; conversely, the fewer switched capacitor units 311 need to be connected in series.

[0077] Multiple switched capacitor units 311 are connected in series to form a cascaded chain 310, which is then connected in parallel with the H-bridge topology 100. Specifically, the positive output terminal of the cascaded chain 310 is connected to the positive terminal of the DC input terminal of the H-bridge topology 100, and the negative output terminal is connected to the negative terminal of the DC input terminal of the H-bridge topology 100. By connecting multiple switched capacitor units 311 in series, the voltages output by each switched capacitor unit 311 are sequentially superimposed, resulting in a total output voltage of the cascaded chain 310 that is the sum of the voltages of each switched capacitor unit 311. In this way, even if each switched capacitor unit 311 can only withstand a low voltage, the combined voltage output can be much higher than that of a single switched capacitor unit 311, thus achieving high-voltage output with a relatively low withstand voltage device, reducing the difficulty of device selection and procurement costs.

[0078] The control module 600 is also used to control the power module 200 to charge each switched capacitor unit 311 separately. For example, the power module 200 may include a power supply device 210 and multiple charging branches 220. The power supply device 210 is a DC output power supply, and the multiple charging branches 220 are all connected to the output terminal of the power supply device 210. Each charging branch 220 is connected to one switched capacitor unit 311, so that the power supply device 210 charges the corresponding switched capacitor unit 311 independently through each charging branch 220. By setting independent charging branches 220 to charge each switched capacitor unit 311 separately, each switched capacitor unit 311 can independently receive charging energy, minimizing the problem of uneven charging of different switched capacitor units 311 and ensuring that each switched capacitor unit 311 can be charged to a preset voltage.

[0079] During the charging process, the control module 600 monitors the voltage of each switched capacitor unit 311 in real time. When all switched capacitor units 311 are charged to the preset voltage, the control module 600 determines that the charging of the energy storage module 300 is complete. For example, let the voltages of X switched capacitor units 311 be V_sm1, V_sm2, ..., V_smX, and the preset voltage be V_ref. Then the flag K indicating that charging is complete can be expressed as K=(V_sm1>V_ref)∧(V_sm2>V_ref)∧…∧(V_smX>V_ref), that is, when the voltage of all switched capacitor units 311 is greater than V_ref, K=1, indicating that charging is complete. By monitoring the charging status of each switched capacitor unit 311, the energy storage module 300 ensures that the energy storage module 300 enters the subsequent discharge stage only after all switched capacitor units 311 have reached the expected energy storage state. This avoids voltage imbalance between units caused by insufficient charging of some switched capacitor units 311 and ensures the accuracy and consistency of the test voltage.

[0080] In some of these embodiments, reference continues. Figure 3 The switched capacitor unit 311 includes an upper switching transistor T1, a lower switching transistor T2, and an energy storage element C; the first end of the upper switching transistor T1 is connected to the first end of the energy storage element C, the second end of the upper switching transistor T1 is connected to the first end of the lower switching transistor T2, the second end of the lower switching transistor T2 is connected to the second end of the energy storage element C, and the power module 200 is connected to the first end of the upper switching transistor T1 and the second end of the lower switching transistor T2 respectively.

[0081] The control module 600 is also used to control both the upper switch T1 and the lower switch T2 to be turned off, so that the power module 200 charges the energy storage element C. When the energy storage element C is charged to the preset voltage, the charging of the switched capacitor unit 311 is completed.

[0082] Both the upper switch T1 and the lower switch T2 are fully controllable power semiconductor switching devices. For example, the upper switch T1 and the lower switch T2 can be integrated gate commutated thyristors (IGCTs), insulated gate bipolar transistors (IGBTs), metal-oxide-semiconductor field-effect transistors (MOSFETs), or a combination of the above devices and an anti-parallel diode. Each of the upper switch T1 and the lower switch T2 has a control terminal, which is connected to the control module 600 to receive drive pulse signals from the control module 600, thereby independently controlling the turn-on and turn-off of the upper switch T1 and the lower switch T2 respectively.

[0083] The upper switching transistor T1 and the lower switching transistor T2 are connected in series to form a series branch. The energy storage element C is connected in parallel to this series branch to form a switched capacitor unit 311. As an example, the energy storage element C can specifically be a capacitor.

[0084] The connection point between the first end of the upper switching transistor T1 and the first end of the energy storage element C forms the first external port of the switched capacitor unit 311, the connection point between the second end of the upper switching transistor T1 and the first end of the lower switching transistor T2 forms the second external port of the switched capacitor unit 311, and the connection point between the second end of the lower switching transistor T2 and the second end of the energy storage element C forms the third external port of the switched capacitor unit 311.

[0085] It should be noted that the "first terminal" and "second terminal" in the above description are relative to the current path of the switching transistor. For IGCT or IGBT, the first terminal can be the collector or anode, and the second terminal can be the emitter or cathode; for MOSFET, the first terminal can be the drain, and the second terminal can be the source.

[0086] In one optional embodiment, the power module 200 is connected to the first terminal of the upper switching transistor T1 and the second terminal of the lower switching transistor T2, that is, the output terminal of the power module 200 is connected between the first external port and the third external port of the switched capacitor unit 311.

[0087] When charging the energy storage module 300, the control module 600 controls both the upper switch transistor T1 and the lower switch transistor T2 of the switched capacitor unit 311 to turn off, and the power supply module 200 charges the energy storage element C in the switched capacitor unit 311. Charging of the switched capacitor unit 311 is completed when the energy storage element C in the switched capacitor unit 311 is charged to a preset voltage.

[0088] In one embodiment, continue to refer to Figure 3 In the cascaded chain of switched capacitor units 310, the second terminal of the lower switch transistor T2 in the previous switched capacitor unit 311 is connected to the first terminal of the lower switch transistor T2 in the next switched capacitor unit 311. The second terminal of the upper switch transistor T1 in the first switched capacitor unit 311 and the second terminal of the lower switch transistor T2 in the last switched capacitor unit 311 are both connected to the DC input terminal of the H-bridge topology 100.

[0089] The control module 600 is also used to control the upper switching transistor T1 in each switched capacitor unit 311 to turn on in a preset turn-on sequence, and to control the lower switching transistor T2 in each switched capacitor unit 311 to remain off, so as to charge the H-bridge topology 100.

[0090] Specifically, taking the preceding switched capacitor unit 311 and the following switched capacitor unit 311 as examples, the second terminal of the lower switching transistor T2 in the preceding switched capacitor unit 311 is connected to the first terminal of the lower switching transistor T2 in the following switched capacitor unit 311, that is, the third external port of the preceding switched capacitor unit 311 is connected to the second external port of the following switched capacitor unit 311. The various switched capacitor units 311 are connected in series in the above manner to form a cascaded switched capacitor unit chain 310.

[0091] The second terminal of the upper switching transistor T1 in the first switched capacitor unit 311 of the switched capacitor unit cascade chain 310 (i.e., the second external port of the first switched capacitor unit 311) is connected to the positive terminal of the DC input terminal of the H-bridge topology 100. The second terminal of the lower switching transistor T2 in the last switched capacitor unit 311 of the switched capacitor unit cascade chain 310 (i.e., the third external port of the last switched capacitor unit 311) is connected to the negative terminal of the DC input terminal of the H-bridge topology 100. In this way, the two ends of the entire switched capacitor unit cascade chain 310 are connected to the positive and negative terminals of the DC input terminal of the H-bridge topology 100, respectively, realizing the parallel connection between the switched capacitor unit cascade chain 310 and the H-bridge topology 100.

[0092] It should be noted that the first switched capacitor unit 311 in the switched capacitor unit cascade chain 310 refers to the switched capacitor unit 311 located at one end of the switched capacitor unit cascade chain 310, and this first switched capacitor unit 311 does not have a preceding switched capacitor unit 311. The last switched capacitor unit 311 in the switched capacitor unit cascade chain 310 refers to the switched capacitor unit 311 located at the other end of the switched capacitor unit cascade chain 310, and this last switched capacitor unit 311 does not have a following switched capacitor unit 311.

[0093] After confirming the completion of charging of each switched capacitor unit 311, the control module 600 controls the upper switching transistor T1 in each switched capacitor unit 311 to turn on according to a preset conduction sequence, and controls the lower switching transistor T2 in each switched capacitor unit 311 to remain off. At this time, the energy storage element C in each switched capacitor unit 311 is sequentially connected to the H-bridge topology 100 and sequentially discharges into the H-bridge topology 100.

[0094] As the number of energy storage elements C connected to the H-bridge topology 100 increases, the test voltage output by the cascaded switching energy storage elements C to the H-bridge topology 100 also increases. Finally, when all the energy storage elements C in the switched capacitor units 311 are discharged, the test voltage output by the cascaded switching energy storage elements C is the sum of the energy storage element voltages of the energy storage elements C in each switched capacitor unit 311.

[0095] The control module 600 turns on the upper switching transistor T1 in each switched capacitor unit 311 according to a preset turn-on sequence, so as to realize the gradual connection of the energy storage element C in each switched capacitor unit 311. As an example, the preset turn-on sequence can be that each switched capacitor unit 311 is turned on sequentially from the first to the last in physical order, or sequentially from the last to the first in physical order.

[0096] In some embodiments, the switched capacitor unit 311 further includes a voltage equalization resistor R1, which is connected in parallel across the energy storage element C. When the energy storage element C of each switched capacitor unit 311 discharges, the voltage equalization resistor R1 equalizes the discharge voltage of each energy storage element C to ensure that the terminal voltage of the energy storage element C in each switched energy storage element C module is basically the same.

[0097] In this embodiment, by controlling the lower switching transistor T2 of each switched capacitor unit 311 to remain off and only sequentially turning on the upper switching transistor T1 of each switched capacitor unit 311, the energy storage elements C of each switched capacitor unit 311 are connected in series and jointly output electrical energy, thus realizing high-voltage charging of the H-bridge topology 100. This charging method does not require an additional step-up transformer or high-voltage charging device; it only needs to utilize the series voltage superposition characteristics of the cascaded switched capacitor unit chain 310 itself to achieve high-voltage output, which helps to reduce testing costs.

[0098] In one embodiment, the first IGCT series valve 110 and the second IGCT series valve 120 are both formed by connecting N IGCT power units 130 in series, where N is an even number greater than or equal to 2, and each IGCT power unit 130 is connected to the control module 600.

[0099] The control module 600 is also used to repeat a preset first control process after charging the H-bridge topology 100 in order to balance the terminal voltage of each IGCT power unit 130.

[0100] The first control process is as follows:

[0101] The terminal voltage of each IGCT power unit 130 is obtained; the terminal voltages of each IGCT are sorted in descending order to obtain the terminal voltage ranking of each IGCT power unit 130; the IGCT power unit 130 whose terminal voltage ranking is in the first N / 2 positions is turned on and maintained for a preset time.

[0102] The first IGCT series valve 110 and the second IGCT series valve 120 are both formed by connecting N IGCT power units 130 in series. Each IGCT power unit 130 includes at least an IGCT chip, a freewheeling diode connected in anti-parallel to the IGCT chip, and a gate drive circuit connected to the gate of the IGCT chip. The gate drive circuit is connected to the control module 600. Of course, the IGCT power unit 130 can also be constructed using other topologies. Those skilled in the art can add additional functional units according to actual needs, which will not be elaborated here.

[0103] The gate drive circuits of each IGCT power unit 130 are connected to the control module 600 to receive turn-on or turn-off commands from the control module 600. Based on the turn-on command, the gate drive circuit outputs a turn-on pulse to the corresponding IGCT chip to control the IGCT power unit 130 to turn on; based on the turn-off command, it outputs a turn-off pulse to the corresponding IGCT chip to control the IGCT power unit 130 to turn off. Simultaneously, the gate drive circuits also report the terminal voltage of the IGCT power unit 130 to the control module 600. In some other examples, the gate drive circuits may also synchronously report other operating parameters of the IGCT power unit 130 to the control module 600, so that the control module 600 can monitor the operating status of the IGCT power unit 130.

[0104] After the H-bridge topology 100 is fully charged, the control module 600 controls each IGCT power unit 130 and repeats the first control process to achieve voltage balancing of each IGCT power unit 130.

[0105] Specifically, the control module 600 first obtains the terminal voltage of each IGCT power unit 130 through the gate drive circuit of each IGCT power unit 130, assuming that the terminal voltages of each IGCT power unit 130 are V_IGCT1, V_IGCT2, ..., V_IGCTN. Then, the control module 600 sorts the obtained N terminal voltages in descending order to obtain an ordered sequence V_IGCT1≥V_IGCT2≥…≥V_IGCTN, and records the index number of the IGCT power unit 130 corresponding to each terminal voltage. Next, the IGCT power units 130 ranked in the first N / 2 positions by the control terminal voltage of the control module 600 are turned on, that is, the gate drive circuits of the IGCT power units 130 ranked from the 1st to the N / 2nd position are controlled to send on pulses, so that these IGCT power units 130 are in the on state; at the same time, the IGCT power units 130 ranked in the last N / 2 positions by the control terminal voltage are turned off, that is, the gate drive circuits of the IGCT power units 130 ranked from the N / 2+1th to the Nth position are controlled not to send on pulses or to send off pulses, so that these IGCT power units 130 are in the off state.

[0106] Based on the above control, since the IGCT power unit 130 is in the on-state, its terminal voltage decreases slightly due to the on-state voltage drop; while the off IGCT power unit 130 continues to receive charging current from the energy storage module 300, and its terminal voltage gradually increases. After maintaining this state for a preset time, the terminal voltage distribution of each IGCT power unit 130 changes—the IGCT power units 130 that were originally ranked higher (higher voltage) experience a decrease in voltage due to being turned on, while the IGCT power units 130 that were originally ranked lower (lower voltage) experience a increase in voltage due to continued charging. The terminal voltage of each IGCT power unit 130 continuously changes, ultimately achieving voltage balance.

[0107] Simultaneously, only the first N / 2 IGCT power units 130 with higher terminal voltages are turned on, while the last N / 2 IGCT power units 130 with lower terminal voltages are turned off. At this time, the current N / 2 IGCT power units 130 evenly share the test voltage output by the energy storage module 300, thereby raising the terminal voltage of the IGCT power units 130.

[0108] As an example, the first control process is maintained for a preset duration. The preset duration can be adaptively set by those skilled in the art based on the actual operating parameters of the IGCT power unit 130 and testing requirements, for example, it can be set to 5 milliseconds or 10 milliseconds.

[0109] In some implementations, the first control process ends when the terminal voltages of all IGCT power units 130 converge to 2U_dc / N. U_dc is the amplitude of the test voltage output by the energy storage module 300.

[0110] In this embodiment, voltage balancing of each IGCT power unit 130 is achieved by controlling the IGCT power unit 130. There is no need to set up an independent equalizing resistor R1 or clamping circuit for each IGCT power unit 130; dynamic voltage balancing of the series-connected IGCT power units 130 can be achieved solely through software control strategies. This avoids breakdown damage caused by excessively high voltage at some IGCT power units 130 or deterioration of switching characteristics caused by excessively low voltage.

[0111] In some implementations, the control module 600 is further configured to acquire the fault detection results of all IGCT power units 130 before performing the first control process, and to perform the first control process if all the fault detection results of all IGCT power units 130 are normal.

[0112] Specifically, after the IGCT power unit 130 is powered on, the gate drive circuit performs fault detection on the IGCT power unit 130. Fault detection may include bus undervoltage fault detection, drive abnormality fault detection, power supply fault detection, etc. After completing the fault detection, the fault detection results are sent to the control module 600. The control module 600 only continues to execute the first control process when it determines that the fault detection results of all IGCT power units 130 are normal.

[0113] In some implementations, the gate drive circuit of the IGCT power unit 130 performs fault detection on the corresponding IGCT power unit 130 Z seconds after the H-bridge topology 100 has finished charging.

[0114] Specifically, since the time it takes for the gate drive circuit and the control module 600 to establish communication after each IGCT power unit 130 is not consistent, the fault detection of the IGCT power unit 130 is set to start after a delay of Z seconds.

[0115] In one embodiment, the control module 600 is further configured to repeat a preset second control process after charging the H-bridge topology 100, so as to adjust the waveform of the test voltage to a positive polarity sine half-wave.

[0116] The second control process is as follows:

[0117] Obtain the energy storage element voltage of all energy storage elements C; in the first half of a half-wave cycle, turn on the upper switch transistor T1 in each switched capacitor unit 311 in descending order of energy storage element voltage, and turn off the lower switch transistor T2 in each switched capacitor unit 311; in the second half of a half-wave cycle, turn off the upper switch transistor T1 in each switched capacitor unit 311 in descending order of energy storage element voltage, and turn on the lower switch transistor T2 in each switched capacitor unit 311.

[0118] After the energy storage module 300 completes charging of the H-bridge topology 100 and the terminal voltages of each IGCT power unit 130 are basically balanced, the control module 600 controls the test platform to enter the normal operation / test phase.

[0119] During this stage, the control module 600 controls the energy storage module 300 to output a test voltage waveform that meets the requirements to the DC input terminal of the H-bridge topology 100, so that the H-bridge topology 100 can further perform polarity reversal processing and output a complete AC waveform to the load module 400.

[0120] Since the energy storage module 300 adopts a cascaded chain 310 structure of switched capacitor units, its output voltage can be adjusted by controlling the on and off combinations of the upper switching transistor T1 and the lower switching transistor T2 in each switched capacitor unit 311. The control module 600, by repeatedly executing the second control process, controls each switched capacitor unit 311 to be switched on or off according to a specific timing sequence, thereby adjusting the waveform of the test voltage to a positive polarity sinusoidal half-wave. A positive polarity sinusoidal half-wave refers to a voltage waveform whose amplitude is always greater than or equal to zero and whose shape is a sinusoidal half-wave; that is, the voltage value of this waveform changes sinusoidally between zero and the positive peak value, without any negative values.

[0121] For example, the test voltage mentioned above is the sum of the energy storage element voltages of the energy storage elements C in each switched capacitor unit 311. During the operation of the test platform, the energy storage elements C in each switched capacitor unit 311 store electrical energy. When the switched capacitor unit 311 is in the on state (i.e., the upper switch T1 is on and the lower switch T2 is off), its energy storage element voltage is output to the total output voltage of the cascade chain; when the switched capacitor unit 311 is in the off state (i.e., the upper switch T1 is off and the lower switch T2 is on), its energy storage element voltage is not output to the total output voltage of the cascade chain.

[0122] Therefore, by controlling whether each switched capacitor unit 311 is in the on or off state at any given time, the total output voltage of the cascaded switched capacitor unit 310 can be controlled. When more switched capacitor units 311 are on, the total output voltage is higher; when fewer switched capacitor units 311 are on, the total output voltage is lower. By dynamically adjusting the number of switched capacitor units 311 on according to a sinusoidal pattern within one half-wave period, a stepped sinusoidal half-wave voltage waveform can be constructed.

[0123] Specifically, in the first half of a half-wave cycle, the control module 600 sequentially turns on the upper switching transistor T1 in each switched capacitor unit 311 in descending order of energy storage element voltage, while simultaneously turning off the lower switching transistor T2 in each switched capacitor unit 311.

[0124] Taking the aforementioned X switched capacitor units 311 as an example, the control module 600 first obtains the energy storage element voltages of the X energy storage elements C, and then sorts them in descending order according to the energy storage element voltages, to obtain an ordered sequence V_sm1≥V_sm2≥…≥V_smX, with the corresponding index numbers of the switched capacitor units 311 being a1, a2, …, aX.

[0125] At the beginning of the half-wave cycle, the control module 600 controls the upper switch T1 of the switched capacitor unit 311 with index number a1 to turn on and the lower switch T2 to turn off, so that the switched capacitor unit 311 is engaged, and the total output voltage of the cascaded switched capacitor unit 310 jumps from zero to V_sm1. As the rising edge of the sine half-wave advances, the control module 600 engages the subsequent switched capacitor units 311 in sequence according to the sorting result, that is, it sequentially turns on the upper switch T1 of the switched capacitor units 311 with index numbers a2, a3, ..., aX, and keeps the engaged switched capacitor units 311 in the on state, so that the total output voltage of the cascaded switched capacitor unit 310 gradually increases, becoming V_sm1+V_sm2, V_sm1+V_sm2+V_sm3, ..., until all X switched capacitor units 311 are engaged, and the total output voltage reaches the sum of the voltages of all energy storage elements ∑V_smi, corresponding to the vicinity of the peak value of the sine half-wave.

[0126] In the latter half of a half-wave cycle, the control module 600 sequentially turns off the upper switching transistor T1 in each switched capacitor unit 311 and turns on the lower switching transistor T2 in each switched capacitor unit 311 in descending order of energy storage element voltage.

[0127] Specifically, after the peak of the sine half-wave, the control module 600 sequentially disconnects the switched capacitor units 311 that have been connected, following the same order as the connection sequence. The control module 600 first turns off the upper switch T1 of the switched capacitor unit 311 with index a1, while simultaneously turning on its lower switch T2, thus bypassing the switched capacitor unit 311 and causing the total output voltage to drop from ∑V_smi to ∑Vsm_i-V_sm1. Then, it turns off the upper switch T1 of the switched capacitor unit 311 with index a2 and turns on its lower switch T2, further reducing the total output voltage. This process continues until all switched capacitor units 311 are disconnected, and the total output voltage drops to zero, corresponding to the end of the sine half-wave.

[0128] In this embodiment, through the second control process described above, within a complete half-wave cycle, the total output voltage of the cascaded switched capacitor unit 310 gradually rises from zero to its maximum value, and then gradually decreases from its maximum value back to zero, thereby constructing a positive sinusoidal half-wave waveform for the test voltage. By adjusting the waveform of the test voltage to a positive sinusoidal half-wave, the voltage waveform output by the energy storage module 300 matches the commutation characteristics of the subsequent H-bridge topology 100. The H-bridge topology 100 only needs to alternately flip once every half-cycle to flip the positive sinusoidal half-wave into a complete bipolar sinusoidal wave, thereby forming a load current.

[0129] In one embodiment, the H-bridge topology 100 has four arms, with the first IGCT series valve 110 forming the first arm QB1 and the second arm QB2 of the H-bridge topology 100, and the second IGCT series valve 120 forming the third arm QB3 and the fourth arm QB4 of the H-bridge topology 100.

[0130] The control module 600 is also used to output an H-bridge pulse to the H-bridge topology 100 after adjusting the waveform of the test voltage to a positive polarity sine half-wave, so as to control the H-bridge topology 100 to perform polarity reversal processing on the test voltage.

[0131] The H-bridge pulse is used to control the first and fourth arms of the H-bridge topology to be turned on during the first half-wave period, and the second and third arms to be turned off during the first half-wave period; and to control the first and fourth arms of the H-bridge topology to be turned off during the second half-wave period, and the second and third arms to be turned on during the second half-wave period.

[0132] The second half-wave period is the next adjacent half-wave period of the first half-wave period.

[0133] In the first IGCT series valve 110, the first N / 2 IGCT power units 130 are connected in series to form the first bridge arm QB1, and the last N / 2 IGCT power units 130 are connected in series to form the second bridge arm QB2. Similarly, in the second IGCT series valve 120, the first N / 2 IGCT power units 130 are connected in series to form the third bridge arm QB3, and the last N / 2 IGCT power units 130 are connected in series to form the fourth bridge arm QB4. The series connection point of the first bridge arm QB1 and the second bridge arm QB2 is led out as one AC output terminal of the H-bridge topology 100, and the series connection point of the third bridge arm QB3 and the fourth bridge arm QB4 is led out as the other AC output terminal of the H-bridge topology 100. One end of the load module 400 is connected to one AC output terminal of the H-bridge topology 100, and the other end is connected to the other AC output terminal of the H-bridge topology 100.

[0134] The control module 600 sends H-bridge pulses to the H-bridge topology 100 to control the four arms of the H-bridge topology 100. An H-bridge pulse refers to the set of drive pulse signals sent by the control module 600 to the gate drive circuits of each IGCT power unit 130 in the H-bridge topology 100. This set of drive pulse signals includes multiple pulse signals corresponding to each IGCT power unit 130 in the first arm QB1, second arm QB2, third arm QB3, and fourth arm QB4, respectively. The timing sequence of each pulse signal is uniformly planned by the control module 600 according to the test frequency and commutation period to ensure that the four arms are turned on or off in a set order.

[0135] After the energy storage module 300 outputs a positive sinusoidal half-wave voltage to the DC input terminal of the H-bridge topology 100, the control module 600 outputs an H-bridge pulse to the H-bridge topology 100. The specific waveform of the H-bridge pulse is as follows: Figure 5 As shown.

[0136] During the first half-wave cycle, the control module 600 controls all IGCT power units 130 in the first bridge arm QB1 and the fourth bridge arm QB4 to turn on, while simultaneously controlling all IGCT power units 130 in the second bridge arm QB2 and the third bridge arm QB3 to turn off. At this time, current flows out from the positive output terminal of the switched capacitor unit cascade chain 310, enters the first bridge arm QB1 through the positive terminal of the DC input terminal of the H-bridge topology 100, passes through each IGCT power unit 130 in the first bridge arm QB1, flows into one end of the load module 400, flows through the load module 400 into the fourth bridge arm QB4, then returns through the fourth bridge arm QB4 to the negative terminal of the DC input terminal of the H-bridge topology 100, and finally flows back to the negative output terminal of the switched capacitor unit cascade chain 310, thus forming a current in one direction on the load module 400.

[0137] During the second half-wave cycle, the control module 600 turns off all IGCT power units 130 in the first bridge arm QB1 and the fourth bridge arm QB4, while simultaneously turning on all IGCT power units 130 in the second bridge arm QB2 and the third bridge arm QB3. At this time, current flows out from the positive output terminal of the switched capacitor unit cascade chain 310, enters the third bridge arm QB3 through the positive terminal of the DC input terminal of the H-bridge topology 100, passes through each IGCT power unit 130 in the third bridge arm QB3, flows into the other end of the load module 400, flows through the load module 400 and enters the second bridge arm QB2, then returns to the negative terminal of the DC input terminal of the H-bridge topology 100, and finally flows back to the negative output terminal of the switched capacitor unit cascade chain 310, thus forming a current in the load module 400 in the opposite direction to the previous one.

[0138] For reference Figure 5 The waveform of the test voltage input to the H-bridge topology 100 is a positive polarity sinusoidal half-wave. Based on the above control process of the H-bridge topology 100, the H-bridge topology 100 alternately flips the current path once in each half-wave cycle, so that the waveform of the voltage on the load module 400 is a complete bipolar sinusoidal wave. Under the action of the bipolar sinusoidal voltage, the load module 400 generates a load current, which flows through the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100, so that each IGCT power unit 130 operates under load.

[0139] In this embodiment, the H-bridge topology 100 is composed of the first IGCT series valve 110 and the second IGCT series valve 120 under test. Therefore, during the polarity reversal process, each IGCT power unit 130 is in a real switching working state. Its conduction loss, switching loss, voltage stress and current stress are all generated under actual load conditions. Based on this, the test results can truly reflect the performance of the IGCT series valve in actual engineering applications.

[0140] In one embodiment, the control module 600 is also used to control the initial voltage output by the power module 200 and / or the on-time ratio of the upper switching transistor T1 in each switched capacitor unit 311, so as to adjust the load current.

[0141] The control module 600 can adjust the load current by adjusting the initial voltage output by the power supply module 200.

[0142] The power supply module 200 is an adjustable DC power supply. Its initial output voltage can be continuously adjusted within a certain range under the control of the control module 600, for example, from 0 to 3000V. When the initial output voltage of the power supply module 200 increases, each switched capacitor unit 311 in the energy storage module 300 can be charged with a higher voltage during the charging phase. Since the test voltage output by the energy storage module 300 is the sum of the energy storage element voltages of each switched capacitor unit 311, the amplitude of the test voltage also increases accordingly. As the amplitude of the test voltage increases, the voltage amplitude applied across the load module 400 also increases accordingly, causing a corresponding change in the load current.

[0143] For example, if the initial voltage adjustment range of the power supply module 200 is 0 to 3000V, the control module 600 can adjust the initial voltage from 1000V to 2000V to increase the load current from 50% to 100% of the rated value, thereby simulating the operating conditions under different voltage levels.

[0144] The control module 600 can also adjust the load current by adjusting the on-time ratio of the upper switching transistor T1 in each switched capacitor unit 311.

[0145] The on-time ratio refers to the ratio of the on-time of the upper switch transistor T1 within one switching cycle to the total on-time of the entire switching cycle. The control module 600 controls the upper switch transistor T1 of each switched capacitor unit 311 to turn on and off according to the set timing sequence, thereby forming a stepped sinusoidal half-wave voltage waveform at the output of the cascaded switched capacitor unit chain 310.

[0146] When the on-time percentage of the upper switch transistor T1 increases, it means that the proportion of time each switched capacitor unit 311 is in the active state (i.e., upper switch transistor T1 is on and lower switch transistor T2 is off) increases within one switching cycle. Therefore, the average value of the test voltage output by the cascaded switched capacitor unit chain 310 increases within one cycle. After this test voltage is applied to the load module 400, the effective value of the load current generated by the load module 400 also increases due to the increase in the average voltage across the load module 400. Conversely, when the on-time percentage decreases, the load current decreases accordingly.

[0147] When the load current on the load module 400 changes, the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100 operate under different conditions. Through this load current adjustment method, the test platform can flexibly adjust the load current over a wide range without replacing specific components of the load module 400 or reconfiguring the circuit topology, achieving rapid switching between different test conditions and effectively improving the applicability and efficiency of the test platform.

[0148] In one embodiment, the test platform further includes a heat dissipation module connected to the energy storage module 300 and the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100, for dissipating heat from the energy storage module 300 and the first IGCT series valve 110 and the second IGCT series valve 120 during the test. As an example, the heat dissipation module may specifically be a water chiller.

[0149] In one embodiment, the test platform further includes a soft starter module 700. The energy storage module 300 is connected to the H-bridge topology 100 via the soft starter module 700. Specifically, the soft starter module 700 is connected in series between the output terminal of the energy storage module 300 and the DC input terminal of the H-bridge topology 100.

[0150] The soft start module 700 includes a current-limiting resistor R2 and a bypass switch S, which are connected in parallel. For example, the bypass switch S can be a contactor, relay, thyristor, or fully controlled power semiconductor switching device, etc., with controllable on / off functionality. The control terminal of the bypass switch S is connected to the control module 600 to receive on / off commands from the control module 600. One end of the current-limiting resistor R2 is connected to the output terminal of the energy storage module 300 (i.e., the positive output terminal of the switched capacitor unit cascade 310), and the other end of the current-limiting resistor R2 is connected to the positive terminal of the DC input terminal of the H-bridge topology 100. The two ends of the bypass switch S are connected in parallel across the two ends of the resistor, i.e., one end of the bypass switch S is connected to the output terminal of the energy storage module 300, and the other end of the bypass switch S is connected to the positive terminal of the DC input terminal of the H-bridge topology 100.

[0151] In some embodiments, the control module 600 is also used to control the bypass switch S to open when the energy storage module 300 outputs a test voltage to the H-bridge topology 100, so that the energy storage module 300 charges the H-bridge topology 100 through the current-limiting resistor R2. When the energy storage module 300 outputs a test voltage to the H-bridge topology 100, the current-limiting resistor R2 prevents instantaneous inrush current from damaging the devices in the first IGCT series valve 110 and the second IGCT series valve 120 in the H-bridge topology 100.

[0152] In some embodiments, the control module 600 is also used to close the bypass switch S to short-circuit the current-limiting resistor R2 after charging the H-bridge topology 100. After the bypass switch S is closed, the current flows through the bypass switch S, and the current-limiting resistor R2 is short-circuited and no longer participates in the charging circuit. Therefore, the power loss on the current-limiting resistor R2 is eliminated, and the power loss on the current-limiting resistor R2 is prevented from affecting the test results.

[0153] This application also provides a testing method that can be applied to the testing platform described in any of the above embodiments. Specifically, the testing method can be executed by the control module 600. (Refer to...) Figure 5 The test method specifically includes the following steps S510 to S540.

[0154] S510: Controls the power supply module 200 to output the initial voltage to the energy storage module 300.

[0155] S520: Controls the energy storage module 300 to output a test voltage based on the initial voltage.

[0156] S530: Controls the H-bridge topology 100 to reverse the polarity of the test voltage in order to generate a load current on the load module 400.

[0157] S540: When a load current is generated on the load module 400, the test signal of the first IGCT series valve 110 and / or the test signal of the second IGCT series valve 120 are acquired by the acquisition module 500, and the test results of the first IGCT series valve 110 and / or the second IGCT series valve 120 are determined.

[0158] Using the above testing method, the initial voltage provided by the power module 200 is boosted by the energy storage module 300 to output the test voltage. A high-voltage testing environment can be constructed using a low-voltage power supply, eliminating the need for a high-voltage DC power supply equivalent to the rated voltage of the IGCT series valve under test, thus reducing the construction cost of the testing platform. Simultaneously, the H-bridge topology 100 reverses the polarity of the test voltage, allowing the load module 400 and the energy storage element in the energy storage module 300 to exchange reactive power to form a load current. Electrical energy can circulate between the load module 400 and the energy storage element, eliminating the need for additional high-power active loads to consume energy, thereby reducing operating energy consumption during the test. Based on this, the acquisition module 500 acquires the test signal of the IGCT series valve under test when a load current is formed, and the control module 600 determines the test result based on the test signal, achieving effective evaluation of the IGCT series valve. Compared to related technologies, this application can complete the performance verification of the IGCT series valve under high-voltage and high-current conditions at a lower testing cost, contributing to reduced testing costs.

[0159] This application also provides an electronic device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the test method described in the above method embodiments.

[0160] In the description of this specification, references to terms such as "some embodiments," "other embodiments," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0161] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0162] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A testing platform, characterized in that, The test platform is used to test the first IGCT series valve and / or the second IGCT series valve in the H-bridge topology; the test platform includes: The power module is used to provide the initial voltage; An energy storage module, the input terminal of which is connected to the output terminal of the power supply module, and the output terminal of which is used to connect to the DC input terminal of the H-bridge topology; The load module is used to connect to the AC output terminal of the H-bridge topology and to exchange reactive power with the energy storage element in the energy storage module to form a load current. The acquisition module is used to connect to the test signal output terminal of the H-bridge topology and to acquire the test signal of the first IGCT series valve and / or the test signal of the second IGCT series valve when the load current is generated. A control module is connected to the power supply module, the energy storage module, and the acquisition module, and is used to connect to the H-bridge topology. The control module controls the power supply module to output the initial voltage to the energy storage module, controls the energy storage module to output a test voltage based on the initial voltage, the test voltage being greater than the initial voltage, and controls the H-bridge topology to perform polarity reversal processing on the test voltage to form the load current on the load module. The control module is also used to acquire test signals through the acquisition module to determine the test results of the first IGCT series valve and / or the second IGCT series valve.

2. The testing platform according to claim 1, characterized in that, The energy storage module includes multiple switched capacitor units, which are connected to the power module. The multiple switched capacitor units are connected in series to form a cascade chain of switched capacitor units, and the cascade chain of switched capacitor units is connected in parallel with the H-bridge topology. The control module is also used to control the power module to charge each of the switched capacitor units respectively, so as to charge all the switched capacitor units to a preset voltage.

3. The testing platform according to claim 2, characterized in that, The switched capacitor unit includes an upper switching transistor, a lower switching transistor, and the energy storage element; the first end of the upper switching transistor is connected to the first end of the energy storage element, the second end of the upper switching transistor is connected to the first end of the lower switching transistor, the second end of the lower switching transistor is connected to the second end of the energy storage element, and the power module is connected to the first end of the upper switching transistor and the second end of the lower switching transistor respectively. The control module is also used to control both the upper and lower switching transistors to turn off, so that the power module can charge the energy storage element to the preset voltage.

4. The testing platform according to claim 3, characterized in that, In the cascaded chain of switched capacitor units, the second end of the lower switch transistor in the preceding switched capacitor unit is connected to the first end of the lower switch transistor in the following switched capacitor unit. The second end of the upper switch transistor in the first switched capacitor unit and the second end of the lower switch transistor in the last switched capacitor unit are both connected to the DC input terminal of the H-bridge topology. The control module is also used to control the upper switching transistors in each of the switched capacitor units to turn on in a preset turn-on sequence, and to control the lower switching transistors in each of the switched capacitor units to remain off, so as to charge the H-bridge topology.

5. The testing platform according to claim 4, characterized in that, Both the first IGCT series valve and the second IGCT series valve are formed by connecting N IGCT power units in series, where N is an even number greater than or equal to 2, and each of the IGCT power units is connected to the control module. The control module is also used to repeat a preset first control process after charging the H-bridge topology to balance the terminal voltage of each IGCT power unit. The first control process is as follows: acquiring the terminal voltage of each IGCT power unit; sorting the terminal voltages of each IGCT in descending order to obtain the terminal voltage ranking of each IGCT power unit; controlling the IGCT power unit whose terminal voltage ranking is in the first N / 2 positions to be turned on and maintaining it for a preset time.

6. The testing platform according to claim 4, characterized in that, The control module is also used to repeat a preset second control process after charging the H-bridge topology, so as to adjust the waveform of the test voltage to a positive polarity sine half-wave. The second control process is as follows: acquiring the energy storage element voltage of all the energy storage elements; in the first half of a half-wave cycle, sequentially turning on the upper switching transistors in each of the switched capacitor units and turning off the lower switching transistors in each of the switched capacitor units in order of energy storage element voltage from high to low; in the second half of a half-wave cycle, sequentially turning off the upper switching transistors in each of the switched capacitor units and turning on the lower switching transistors in each of the switched capacitor units in order of energy storage element voltage from high to low.

7. The testing platform according to claim 6, characterized in that, The H-bridge topology has four arms. The first IGCT series valve constitutes the first and second arms of the H-bridge topology, and the second IGCT series valve constitutes the third and fourth arms of the H-bridge topology. The control module is also used to output an H-bridge pulse to the H-bridge topology after adjusting the waveform of the test voltage to a positive polarity sine half-wave, so as to control the H-bridge topology to perform polarity reversal processing on the test voltage. The H-bridge pulse is used to control the first and fourth arms of the H-bridge topology to be turned on during the first half-wave period, and the second and third arms to be turned off during the first half-wave period; and to control the first and fourth arms of the H-bridge topology to be turned off during the second half-wave period, and the second and third arms to be turned on during the second half-wave period; the second half-wave period is the next adjacent half-wave period of the first half-wave period.

8. The testing platform according to claim 4, characterized in that, The control module is also used to control the initial voltage output by the power module and / or the on-time ratio of the upper switching transistor in each of the switched capacitor units, so as to adjust the load current.

9. A testing method, characterized in that, The test platform is applied to any one of claims 1 to 8; the test method includes: The control power module outputs an initial voltage to the energy storage module; The energy storage module is controlled to output the test voltage based on the initial voltage; The H-bridge topology is controlled to reverse the polarity of the test voltage in order to generate the load current on the load module; When the load current is generated on the load module, the test signal of the first IGCT series valve and / or the test signal of the second IGCT series valve are acquired by the acquisition module to determine the test result of the first IGCT series valve and / or the test result of the second IGCT series valve.

10. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the test method of claim 9.

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