Performance test equipment and test method for thyristor and IGBT (Insulated Gate Bipolar Translator) series system

Abstract

The invention relates to a device and a method for testing the performance of a thyristor and IGBT series system, and the device comprises a combination wave generator, the output end of which is connected to the series system, the series system comprises a thyristor and an IGBT module which are connected in series; the voltage divider is connected with the series system in parallel; the current sensor is connected in series with the series system; the input end of the oscilloscope is connected with the output end of the voltage divider and the output end of the current sensor; the input end of the IGBT trigger is connected with the output end of the voltage divider, and the output end of the IGBT trigger is connected with the signal input end of the IGBT module to control the on-off of the IGBT module; the combined wave generator is configured to generate and send an impact voltage signal to the series system when the IGBT module is disconnected, and generate and send an impact current signal to the series system when the IGBT module is connected. Compared with the prior art, the device has the advantages that the size can be reduced, and subsequent signal processing can be simplified.

Description

Technical Field

[0001] The invention relates to the field of grounding network testing of power systems, and in particular to performance testing equipment and a testing method for a thyristor and IGBT series system. Background Art

[0002] Traditional grid-commutated high voltage direct current (LCC-HVDC) transmission systems mostly use thyristors as converters. This method is prone to commutation failure in the event of AC system failure, resulting in a surge in DC current and a rapid and large loss of DC transmission power, affecting the stable and safe operation of the power grid. The controllable-line-commutated converter (CLCC) valve technology based on thyristors and IGBTs in series can achieve 100% resistance to commutation failures, and this technology has begun engineering implementation.

[0003] At present, the test of a single thyristor or IGBT is relatively mature, and the low-voltage test technology for the entire CLCC system has also been developed. However, the key component of the CLCC converter valve is the series structure of thyristors and IGBTs, which will be subjected to high voltage and large current during operation. However, there is a lack of overall test equipment for the series structure of thyristors and IGBTs. If the combination of independent test devices for thyristors and IGBTs in the existing technology is used, on the one hand, the size of the test device will be too large, and on the other hand, the test efficiency will be too low, and the signal processing will be difficult. Summary of the invention

[0004] The purpose of the present invention is to provide a performance testing device and a testing method for a thyristor and IGBT series system.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A performance test device for a thyristor and IGBT series system, comprising:

[0007] A combination wave generator, the output end of which is connected to a series system, wherein the series system includes a thyristor and an IGBT module connected in series;

[0008] A voltage divider, connected in parallel with the series system;

[0009] The current sensor is connected in series with the series system;

[0010] An oscilloscope, the input end of which is respectively connected to the output end of the voltage divider and the output end of the current sensor;

[0011] An IGBT trigger, whose input end is connected to the output end of the voltage divider, and whose output end is connected to the signal input end of the IGBT module to control the on and off of the IGBT module;

[0012] The combination wave generator is configured to generate and send an impulse voltage signal to the series system when the IGBT module is disconnected, and to generate and send an impulse current signal to the series system when the IGBT module is turned on.

[0013] The combination wave generator comprises:

[0014] Impact signal output terminal;

[0015] An impulse voltage generating unit, whose output end is connected to the impulse signal output end;

[0016] An impulse current generating unit, whose output end is connected to the impulse signal output end;

[0017] A controller and a load sampling unit, wherein the input end of the load sampling unit is connected to the impulse signal output end, and the output end is connected to the controller, the controller is respectively connected to the impulse voltage generating unit and the impulse voltage generating unit, and the controller is configured to: when the load sampling unit detects that the load is open-circuited, control the impulse voltage generating unit to generate an impulse voltage signal and output it from the impulse signal output end, and when the load sampling unit detects that the load is short-circuited, control the impulse current generating unit to generate an impulse current signal and output it from the impulse signal output end.

[0018] The load sampling unit is a current sampling unit.

[0019] The load sampling unit includes a first comparator, a second comparator, an AND gate, a first low-voltage power supply, a second low-voltage power supply and a third low-voltage power supply. The inverting input of the first comparator is connected to the first low-voltage power supply, and the non-phase input is connected to the impact signal output and the second low-voltage power supply. The inverting input of the second comparator is connected to the impact signal output and the second low-voltage power supply, and the non-phase input is connected to the third low-voltage power supply. The two inputs of the AND gate are respectively connected to the inputs of the two comparators, and the output is connected to a controller. The voltage of the first low-voltage power supply is lower than that of the second low-voltage power supply, and the voltage of the second low-voltage power supply is lower than that of the third low-voltage power supply.

[0020] The current sensor is a Rogowski coil or a series shunt.

[0021] The current sensor is in a socket connection form.

[0022] The oscilloscope has a bandwidth of 500 MHz.

[0023] A testing method based on the above-mentioned testing device comprises:

[0024] Step S1: When the test starts, the IGBT module is in a disconnected state, and the combination wave generator generates and sends an impulse voltage signal to the series system;

[0025] Step S2: the IGBT trigger monitors the output of the voltage divider, and when the voltage signal output by the voltage divider reaches a peak value, controls the IGBT module to be turned on;

[0026] Step S3: When the IGBT module is turned on, the combination wave generator generates and sends an impulse current signal to the series system;

[0027] Step S4: Obtain the waveform of the oscilloscope, and extract the time t1 from the starting point of the first rising edge to the first peak, and the time t2 from the second rising edge to the second peak;

[0028] Step S5: respectively calculating the difference between t1 and the peak time of the impulse voltage signal as the first deviation error, and the difference between t2 and the impulse current signal as the second deviation error;

[0029] Step S6: If the first deviation error is greater than the first set threshold, or the second deviation error is greater than the second set threshold, it is determined that a fault exists in the series system.

[0030] The first set threshold value and the second set threshold value are equal.

[0031] The peak time of the impulse voltage signal is 1.2 microseconds, and the peak time of the impulse current signal is 8 microseconds.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] 1. By designing a combination wave generator and connecting the IGBT trigger to the output end of the voltage divider, and combining the combination wave generator to generate and send an impulse voltage signal to the series system when the IGBT module is disconnected, and to generate and send an impulse current signal to the series system when the IGBT module is turned on, the voltage signal and the current signal can be separated in the oscilloscope image, thereby reducing the size on the one hand and reducing the difficulty of signal processing on the other hand.

[0034] 2. Based on the load sampling unit, the trigger signal of the working state of the combination wave generator can be obtained. On the one hand, the combination wave generator can automatically generate an impact current signal. On the other hand, the compactness of the signal can be improved and the test efficiency can be improved.

[0035] 3. By using the IGBT module conduction at a specific time, the ability of the thyristor and IGBT series system to withstand high voltage and high current is tested simultaneously in one test, thereby improving the test efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is a structural schematic diagram of the present invention;

[0037] Figure 2 Schematic diagram of signal acquisition for oscilloscope;

[0038] Among them: 1. Combination wave generator, 2. Thyristor, 3. IGBT module, 4. Voltage divider, 5. Current sensor, 6. Oscilloscope, 7. IGBT trigger. DETAILED DESCRIPTION

[0039] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0040] Example 1

[0041] A performance test device for a thyristor and IGBT series system, such as Figure 1 As shown, including:

[0042] A combination wave generator 1, the output end of which is connected to a series system, wherein the series system includes a thyristor 2 and an IGBT module 3 connected in series;

[0043] A voltage divider 4 is connected in parallel with the series system;

[0044] The current sensor 5 is connected in series with the series system;

[0045] An oscilloscope 6, whose input end is respectively connected to the output end of the voltage divider 4 and the output end of the current sensor 5;

[0046] An IGBT trigger 7, whose input end is connected to the output end of the voltage divider 4, and whose output end is connected to the signal input end of the IGBT module 3 to control the on and off of the IGBT module 3;

[0047] The combination wave generator 1 is configured to generate and send an impulse voltage signal to the series system when the IGBT module 3 is turned off, and to generate and send an impulse current signal to the series system when the IGBT module 3 is turned on.

[0048] By designing a combination wave generator 1, connecting the IGBT trigger 7 to the output end of the voltage divider 4, and combining the combination wave generator 1 to generate and send an impulse voltage signal to the series system when the IGBT module 3 is disconnected, and to generate and send an impulse current signal to the series system when the IGBT module 3 is turned on, the voltage signal and the current signal can be separated in the image of the oscilloscope 6, thereby reducing the volume on the one hand and reducing the difficulty of signal processing on the other hand.

[0049] In some embodiments, the combination wave generator 1 comprises:

[0050] Impact signal output terminal;

[0051] An impulse voltage generating unit, the output end of which is connected to the impulse signal output end;

[0052] An impulse current generating unit, the output end of which is connected to the impulse signal output end;

[0053] A controller and a load sampling unit, wherein the input end of the load sampling unit is connected to the impulse signal output end, and the output end is connected to the controller, the controller is respectively connected to the impulse voltage generating unit and the impulse voltage generating unit, and the controller is configured to: when the load sampling unit detects that the load is open-circuited, control the impulse voltage generating unit to generate an impulse voltage signal and output it from the impulse signal output end, and when the load sampling unit detects that the load is short-circuited, control the impulse current generating unit to generate an impulse current signal and output it from the impulse signal output end.

[0054] In this way, a trigger signal of the working state of the combination wave generator can be obtained based on the load sampling unit. On the one hand, the combination wave generator can automatically generate an impact current signal. On the other hand, the compactness of the signal can be improved, thereby improving the test efficiency.

[0055] In some of the embodiments, the load sampling unit is a current sampling unit, and whether the load is short-circuited is determined by whether the current increases. Of course, in other embodiments, a comparator design can also be used, and the load sampling unit includes a first comparator, a second comparator, an AND gate, a first low-voltage power supply, a second low-voltage power supply, and a third low-voltage power supply. The inverting input of the first comparator is connected to the first low-voltage power supply, and the positive input is connected to the impact signal output and the second low-voltage power supply. The inverting input of the second comparator is connected to the impact signal output and the second low-voltage power supply, and the positive input is connected to the third low-voltage power supply. The two inputs of the AND gate are respectively connected to the inputs of the two comparators, and the output is connected to the controller. The voltage of the first low-voltage power supply is less than that of the second low-voltage power supply, and the voltage of the second low-voltage power supply is less than that of the third low-voltage power supply. In this way, when the load is short-circuited, the output of the AND gate is 0, and when the load is disconnected, the output of the AND gate is 1.

[0056] In this embodiment, the current sensor 5 is a Rogowski coil or a series-connected shunt, the current sensor 5 is in a socket-connected form, and the oscilloscope 6 is an oscilloscope with a bandwidth of 500 MHz.

[0057] Example 2

[0058] In addition, the present application also provides a testing method based on the above-mentioned testing device, including:

[0059] Step S1: When the test starts, the IGBT module 3 is in a disconnected state, and the combination wave generator 1 generates and sends an impulse voltage signal to the series system;

[0060] Step S2: the IGBT trigger 7 monitors the output of the voltage divider 4, and when the voltage signal output by the voltage divider 4 reaches a peak value, the IGBT module 3 is controlled to be turned on;

[0061] Step S3: When the IGBT module 3 is turned on, the combination wave generator 1 generates and sends an impulse current signal to the series system;

[0062] Step S4: Obtain the waveform of the oscilloscope 6, and extract the time t1 from the starting point of the first rising edge to the first peak, and the time t2 from the second rising edge to the second peak;

[0063] Step S5: respectively calculating the difference between t1 and the peak time of the impulse voltage signal as the first deviation error, and the difference between t2 and the impulse current signal as the second deviation error;

[0064] Step S6: If the first deviation error is greater than the first set threshold, or the second deviation error is greater than the second set threshold, it is determined that a fault exists in the series system.

[0065] In this embodiment, the first set threshold value and the second set threshold value are equal to each other, both being 20%, the peak time of the impulse voltage signal is 1.2 microseconds, and the peak time of the impulse current signal is 8 microseconds.

[0066] In one embodiment, the signal measured by the oscilloscope during the whole process is as follows Figure 2 As shown. At time t, the IGBT is turned on. Before time t, there is an impulse voltage signal, and after time t, there is an impulse current signal. The waveform rise time t1 of the impulse voltage signal before time t and the waveform rise time t2 of the impulse current signal after time t are calculated. When t1 deviates from 1.2 microseconds ± 20% and t2 deviates from 8 microseconds ± 20%, it is determined that the series system has a fault.

[0067] If the above functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc., which can store program code.

Claims

1. A performance test device for a thyristor and IGBT series system, characterized in that: include: A combination wave generator (1), the output end of which is connected to a series system, wherein the series system comprises a thyristor (2) and an IGBT module (3) connected in series; A voltage divider (4) connected in parallel with the series system; A current sensor (5) is connected in series with the series system; An oscilloscope (6), the input end of which is respectively connected to the output end of the voltage divider (4) and the output end of the current sensor (5); An IGBT trigger (7), the input end of which is connected to the output end of the voltage divider (4), and the output end of which is connected to the signal input end of the IGBT module (3) to control the on and off of the IGBT module (3); The combination wave generator (1) is configured to generate and send an impulse voltage signal to the series system when the IGBT module (3) is disconnected, and to generate and send an impulse current signal to the series system when the IGBT module (3) is turned on.

2. The performance test equipment of a thyristor and IGBT series system according to claim 1, characterized in that: The combination wave generator (1) comprises: Impact signal output terminal; An impulse voltage generating unit, whose output end is connected to the impulse signal output end; An impulse current generating unit, whose output end is connected to the impulse signal output end; A controller and a load sampling unit, wherein the input end of the load sampling unit is connected to the impulse signal output end, and the output end is connected to the controller, the controller is respectively connected to the impulse voltage generating unit and the impulse voltage generating unit, and the controller is configured to: when the load sampling unit detects that the load is open-circuited, control the impulse voltage generating unit to generate an impulse voltage signal and output it from the impulse signal output end, and when the load sampling unit detects that the load is short-circuited, control the impulse current generating unit to generate an impulse current signal and output it from the impulse signal output end.

3. The performance test equipment of a thyristor and IGBT series system according to claim 2, characterized in that: The load sampling unit is a current sampling unit.

4. The performance test equipment of a thyristor and IGBT series system according to claim 2, characterized in that: The load sampling unit includes a first comparator, a second comparator, an AND gate, a first low-voltage power supply, a second low-voltage power supply and a third low-voltage power supply. The inverting input of the first comparator is connected to the first low-voltage power supply, and the non-phase input is connected to the impact signal output and the second low-voltage power supply. The inverting input of the second comparator is connected to the impact signal output and the second low-voltage power supply, and the non-phase input is connected to the third low-voltage power supply. The two inputs of the AND gate are respectively connected to the inputs of the two comparators, and the output is connected to a controller. The voltage of the first low-voltage power supply is lower than that of the second low-voltage power supply, and the voltage of the second low-voltage power supply is lower than that of the third low-voltage power supply.

5. The performance test equipment of a thyristor and IGBT series system according to claim 1, characterized in that: The current sensor (5) is a Rogowski coil or a series-connected shunt.

6. The performance test equipment of a thyristor and IGBT series system according to claim 5, characterized in that: The current sensor (5) is in a socket connection form.

7. The performance test equipment of a thyristor and IGBT series system according to claim 1, characterized in that: The oscilloscope (6) has a bandwidth of 500 MHz.

8. A testing method based on the testing device according to any one of claims 1 to 7, characterized in that: include: Step S1: When the test starts, the IGBT module (3) is in a disconnected state, and the combination wave generator (1) generates and sends an impulse voltage signal to the series system; Step S2: the IGBT trigger (7) monitors the output of the voltage divider (4), and when the voltage signal output by the voltage divider (4) reaches a peak value, controls the IGBT module (3) to be turned on; Step S3: when the IGBT module (3) is turned on, the combination wave generator (1) generates and sends an impulse current signal to the series system; Step S4: Obtain the waveform of the oscilloscope (6), and extract the time t1 from the start of the first rising edge to the first peak, and the time t2 from the second rising edge to the second peak; Step S5: respectively calculating the difference between t1 and the peak time of the impulse voltage signal as the first deviation error, and the difference between t2 and the impulse current signal as the second deviation error; Step S6: If the first deviation error is greater than the first set threshold, or the second deviation error is greater than the second set threshold, it is determined that a fault exists in the series system.

9. The testing method according to claim 8, characterized in that: The first set threshold value and the second set threshold value are equal.

10. The testing method according to claim 9, characterized in that: The peak time of the impulse voltage signal is 1.2 microseconds, and the peak time of the impulse current signal is 8 microseconds.

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