Thyristor tester for converter valve

Abstract

The invention discloses a thyristor tester for a converter valve, which relates to the technical field of thyristor test equipment and comprises a display interaction touch screen, a central processing unit, a blocking test unit, a voltage drop test unit, a resistance-capacitance absorption test unit, a board card trigger capability test unit and a switching unit. The blocking test unit, the voltage drop test unit, the resistance-capacitance absorption test unit and the board card trigger capability test unit are all connected between the central processing unit and the switching unit, and the display interaction touch screen is connected with the central processing unit. The thyristor tester for the converter valve is reasonable in architecture and is composed of a blocking test unit, a voltage drop test unit, an RC resistance-capacitance absorption test unit and a board card communication test unit, all the units are clear in function and cooperate with one another, actual working conditions can be effectively simulated, and key parameters of a thyristor are comprehensively tested.

Description

Technical Field

[0001] The invention relates to the technical field of thyristor testing equipment, in particular to a thyristor tester for a commutator valve. Background Art

[0002] Most of the conventional (UHVDC) projects currently in operation are built based on thyristor commutation technology, and thyristor commutator valves are generally used as the main AC-DC conversion equipment. This type of commutator valve uses thyristors as core components, and is equipped with other components such as damping circuits, anode reactors, and voltage-shaping capacitors to meet the electrical characteristics requirements during transient commutation. It is also equipped with a special valve control device to trigger and control it. Once the commutator valve equipment and its valve control device fail, it will inevitably have a serious impact on the safe and stable operation of the DC transmission project. In recent years, commutator valve failure has become one of the key reasons for the tripping of DC projects.

[0003] The operating years of the earliest projects put into operation in my country have exceeded or approached 20 years, and the aging problem of converter valve equipment has gradually become prominent. However, there are relatively few studies on the aging failure mechanism of converter valves and valve control equipment. What is more difficult is that the on-site operation and maintenance personnel do not have a deep understanding of the status of the converter valve equipment. The main reasons are as follows: On the one hand, there are serious defects in the on-site detection methods and means for thyristor equipment. For example, at present, thyristors mainly use Siemens thyristor testers as valve-level detection equipment. Although this equipment can detect light-controlled and electric-controlled thyristors, it cannot detect the reverse blocking performance, off-state blocking performance and BOD function of thyristors at rated voltage, which leaves a blank area for fault identification. Moreover, other converter valve equipment is not equipped with special detection devices. Therefore, it is imperative to design and process a set of thyristor key parameter test modules.

[0004] On the other hand, the time available for converter valve inspection is very limited, while a lot of equipment needs to be inspected. According to actual DC maintenance experience, the maintenance time of a single valve hall is only 1-2 days, but there are nearly a thousand thyristor devices alone. Therefore, it is necessary to develop special valve control inspection tools, which can reduce the maintenance burden of on-site personnel, enhance the understanding of the status of converter valve equipment, and improve the reliability of DC operation. In addition, key equipment such as converter valves in the earliest projects already need to be evaluated for their operational reliability and operational life. New HVDC projects also need to evaluate the service life of equipment and operational reliability in various environments from a more scientific and long-term management perspective. Summary of the invention

[0005] In view of this, the present invention aims at the deficiencies in the prior art and provides a thyristor tester for a converter valve.

[0006] In order to solve the above technical problems, the technical solution adopted by the present invention is: a thyristor tester for a converter valve, comprising a display interactive touch screen, a central processing unit, a blocking test unit, a voltage drop test unit, a resistor-capacitor absorption test unit, a board trigger capability test unit and a switching unit, wherein the blocking test unit, the voltage drop test unit, the resistor-capacitor absorption test unit, and the board trigger capability test unit are all connected between the central processing unit and the switching unit, and the display interactive touch screen is connected to the central processing unit.

[0007] Furthermore, the blocking test unit includes two parts: a DC test and a half-wave test, and the DC test is configured as follows:

[0008] Voltage adjustment range parameter V DC :Voltage range 1.00~5.00kV, resolution 0.01kV, accuracy ±3%;

[0009] Current parameter I DC :Current range 1.0~100.0mA, resolution 0.1mA, accuracy ±3%±

[0010] 0.2mA;

[0011] The half-wave test configuration is:

[0012] Off-state and reverse peak voltage adjustment range parameter V DRM / V RRM :Voltage range 1.00~8.50kV, resolution 0.01kV, accuracy ±3%;

[0013] Current parameter I DRM / I RRM :Current range 1.0~20.0mA, resolution 0.1mA, accuracy ±3%±

[0014] 0.2mA.

[0015] Further, the voltage drop test unit is configured as follows:

[0016] Current parameter I: 3A, resolution 1A, accuracy ±3% ±0.2A;

[0017] Voltage parameter range V: 0.50~5.00V, resolution 0.01V, accuracy ±3%±0.02V.

[0018] Furthermore, the RC absorption test unit is configured as follows:

[0019] Resistance parameter R: 10.0~50.0Ω, resolution 0.1Ω, accuracy ±3%±0.5Ω;

[0020] Capacitance parameters C: 1.00~5.00uF, resolution 0.01uF, accuracy ±3%±0.1uF.

[0021] Furthermore, the board trigger capability test unit is used to detect the TCU board trigger capability and transceiver status, the TVM board sending status and the RPU board trigger capability.

[0022] Furthermore, when the blocking test unit is in direct current testing, the waveform is a direct current waveform, the voltage sampling point is at the 5ms position, and the current sampling point is also at the 5ms position;

[0023] The DC test method of a single element is: start outputting from 0, increase the voltage incrementally at a speed of 3% of the set value, and detect the blocking condition;

[0024] The DC test method of the valve assembly is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, maintain it for 200ms after the voltage reaches 1000V, detect the leakage current and calculate the current load resistance; then continue to increase the voltage, and the displayed leakage current becomes the sampling current-(voltage / load resistance); by default, the thyristor leakage current is very small at 1000V; compare the differences of each small valve group horizontally to find out the abnormal thyristor;

[0025] When the blocking test unit performs a half-wave test, the waveform is a sine half-wave, the voltage sampling point is at the 5ms position, the current sampling point is also at the 5ms position, and the current protection point is between 0-5ms;

[0026] The half-wave test method of a single element is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, and detect the blocking condition.

[0027] Further, the voltage drop test unit uses a transformer as a pulse current source for test scheme 3A;

[0028] The test method of the electric control valve body is as follows: provide energy to the TCU board through a 150V / 200W transformer, trigger the thyristor under test through the TCU board at a delay of 5ms after detecting the synchronous rising edge, sample the voltage drop multiple times 100us after triggering, sample the voltage when the 3A current is detected, and detect the feedback of the TCU board after completion. After judging the status of the board, measure the thyristor voltage drop;

[0029] The test method of the light-controlled valve body is as follows: provide energy to the RPU board through a 150V / 200W transformer, and send out an optical signal through the RPU board after a 5ms delay after detecting the synchronous rising edge. After passing through the optical splitter, the light-controlled thyristor in the valve section is triggered. After the triggering, the voltage is sampled when the 3A current is detected. After completion, the feedback from the TVM board is detected, and the status of the TVM board is judged at the same time, completing the voltage drop test and board detection process at one time.

[0030] Furthermore, the test method of the RC absorption test unit is:

[0031] First, use a constant current source to charge the capacitor and measure the loop capacitance:

[0032] I×ΔT=ΔV×C

[0033] The two time intervals ΔT are known, the voltage is sampled twice at the corresponding two times to obtain ΔV, and the constant current I is also known. The size of the capacitor C is calculated according to the formula;

[0034] Then, the CPU controls the high-frequency generator to emit a high-frequency sine wave, which is then passed through the signal amplifier to generate a high-frequency voltage source of a certain power, which is applied to both ends of the RC loop to measure the loop resistance:

[0035] Xc=1 / (2πfC)

[0036] (U / I) 2 =R 2 +Xc 2 .

[0037] Further, the TCU board and the RPU board are tested in the following manner: whether the TCU board and the RPU board can normally trigger the thyristor under test during the voltage drop test unit test is used to determine whether the RPU board functions normally;

[0038] The TVM board test method is: after loading 330V AC power supply voltage on the TVM board, whether the TVM board generates a return check signal is used to determine whether the function is normal.

[0039] Furthermore, it also includes a first box and a second box, the central processing unit, the switching unit and the blocking test unit are installed in the first box, the display interactive touch screen is installed in the box cover of the first box, the voltage drop test unit, the resistance-capacitance absorption test unit and the board triggering ability test unit are installed in the second box, the first box and the second box are connected through a panel-embedded multi-wire plug, and the test line is output from the first box.

[0040] Compared with the prior art, the present invention has the following beneficial effects:

[0041] The thyristor tester for the commutation valve of the present invention is composed of 4 test sub-units. The first test sub-unit is a blocking test unit. This unit undertakes specific blocking test-related tasks in the entire module. It accurately detects and analyzes the blocking conditions of signals or currents, etc. The second is a voltage drop test unit, which is mainly responsible for testing the voltage drop. It can accurately measure the corresponding voltage drop value under a certain current. The third is a resistance-capacitance absorption test unit. This unit focuses on testing the conditions related to resistance-capacitance absorption. For the combination of resistance and capacitance in the circuit, only two lines need to be connected to be able to detect. Compared with the previous resistance test using a resistance meter and then the capacitance test using a capacitance meter, the test time is saved. The last one is a board triggering ability test unit. Its core function is to test the communication conditions between boards, ensure that the data transmission between boards is stable, efficient and accurate, and control the conduction of the tested device through the unit to assist in completing the test of the voltage drop unit. These four test sub-units complement each other and jointly build the architecture system of the entire module, realizing comprehensive and accurate detection of key device thyristors and thyristors containing peripheral related devices.

[0042] The thyristor tester for the converter valve of the present invention adopts a double-box structure, the central processing unit, the switching unit and the blocking test unit are installed in the first box, the display interactive touch screen is installed in the box cover of the first box, the voltage drop test unit, the resistance-capacitance absorption test unit and the board triggering ability test unit are installed in the second box, the two boxes are connected through the panel embedded multi-wire plug, and the test line is output from the first box. It is small in size, easy to carry, and can be used for qualitative or quantitative testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is an overall architecture diagram of an embodiment of the present invention;

[0044] Figure 2 is a circuit diagram of a switching unit in an embodiment of the present invention;

[0045] Figure 3 is a circuit diagram of an automatic boost module in an embodiment of the present invention;

[0046] Figure 4 is a circuit diagram of a voltage drop test unit in an embodiment of the present invention;

[0047] Figure 5 is a structural block diagram of a resistance-capacitance absorption test unit in an embodiment of the present invention;

[0048] Figure 6 It is a structural schematic diagram of the first box body in an embodiment of the present invention. DETAILED DESCRIPTION

[0049] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0050] Example: Refer to Figure 1 A thyristor tester for a converter valve comprises a display interactive touch screen, a central processing unit, a blocking test unit, a voltage drop test unit, a resistor-capacitor absorption test unit, a board trigger capability test unit and a switching unit, wherein the blocking test unit, the voltage drop test unit, the resistor-capacitor absorption test unit and the board trigger capability test unit are all connected between the central processing unit and the switching unit, and the display interactive touch screen is connected to the central processing unit.

[0051] The switching unit is connected to the module under test (thyristor unit or valve assembly) and is used to switch different test units to test the module under test.

[0052] like Figure 2 As shown, the switching unit uses an integrated 8-way relay switching board as the control core. The biggest advantage of this board is that it can be directly connected to the processor output I / O port, has a built-in isolation optocoupler, and has strong anti-interference performance.

[0053] The blocking test unit includes two parts: DC test and half-wave test. The DC test configuration is:

[0054] Voltage adjustment range parameter V DC :Voltage range 1.00~5.00kV, resolution 0.01kV, accuracy ±3%;

[0055] Current parameter I DC :Current range 1.0~100.0mA, resolution 0.1mA, accuracy ±3%±

[0056] 0.2mA;

[0057] The half-wave test configuration is:

[0058] Off-state and reverse peak voltage adjustment range parameter V DRM / V RRM :Voltage range 1.00~8.50kV, resolution 0.01kV, accuracy ±3%;

[0059] Current parameter I DRM / I RRM :Current range 1.0~20.0mA, resolution 0.1mA, accuracy ±3%±

[0060] 0.2mA.

[0061] When the blocking test unit is tested in DC, the waveform is a DC waveform, the voltage sampling point is at the 5ms position, the current sampling point is also at the 5ms position, but the current protection point is all the time except after processing other matters such as the serial port.

[0062] like Figure 3 As shown, the blocking test unit adopts an automatic boost module, which controls the high voltage proportionally through the D / A control of the central processing unit, thereby adjusting the final applied voltage.

[0063] The DC test method of a single device is: the central processor controls the digital-to-analog converter DA to output from 0, and increases the voltage incrementally at a speed of 3% of the set value to detect the blocking condition;

[0064] The DC test method of the valve assembly is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, maintain it for 200ms after the voltage reaches 1000V, detect the leakage current and calculate the current load resistance; then continue to increase the voltage, and the displayed leakage current becomes the sampling current-(voltage / load resistance); by default, the thyristor leakage current is very small at 1000V; compare the differences of each small valve group horizontally to find out the abnormal thyristor;

[0065] When the blocking test unit is in half-wave test, the waveform is a sine half-wave, the voltage sampling point is at 5ms, the current sampling point is also at 5ms, and the current protection point is between 0-5ms;

[0066] The half-wave test method of a single element is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, and detect the blocking condition.

[0067] The voltage drop test unit is configured as:

[0068] Current parameter I: 3A, resolution 1A, accuracy ±3% ±0.2A;

[0069] Voltage parameter range V: 0.50~5.00V, resolution 0.01V, accuracy ±3%±0.02V.

[0070] like Figure 4 As shown, the voltage drop test unit uses a transformer as the 3A pulse current source for the test scheme;

[0071] The test method of the electric control valve body is as follows: provide energy to the TCU board through a 150V / 200W transformer, trigger the thyristor under test through the TCU board at a delay of 5ms after detecting the synchronous rising edge, sample the voltage drop multiple times 100us after triggering, sample the voltage when the 3A current is detected, and detect the feedback of the TCU board after completion. After judging the status of the board, measure the thyristor voltage drop;

[0072] The test method of the light-controlled valve body is as follows: provide energy to the RPU board through a 150V / 200W transformer, and send out an optical signal through the RPU board after a 5ms delay after detecting the synchronous rising edge. After passing through the optical splitter, the light-controlled thyristor in the valve section is triggered. After the triggering, the voltage is sampled when the 3A current is detected. After completion, the feedback from the TVM board is detected, and the status of the TVM board is judged at the same time, completing the voltage drop test and board detection process at one time.

[0073] The RC absorption test unit is configured as follows:

[0074] Resistance parameter R: 10.0~50.0Ω, resolution 0.1Ω, accuracy ±3%±0.5Ω;

[0075] Capacitance parameters C: 1.00~5.00uF, resolution 0.01uF, accuracy ±3%±0.1uF.

[0076] The test method of the resistance-capacitance absorption test unit is:

[0077] First, use a constant current source to charge the capacitor and measure the loop capacitance:

[0078] I×ΔT=ΔV×C

[0079] The two time intervals ΔT are known, the voltage is sampled twice at the corresponding two times to obtain ΔV, and the constant current I is also known. The size of the capacitor C is calculated according to the formula;

[0080] Then, if Figure 5 As shown, the interactive touch screen communicates with the central processor MCU via serial port. The central processor controls the high-frequency generator to emit a high-frequency sine wave, which is then passed through the signal amplifier to generate a high-frequency voltage source with a certain power. The high-frequency voltage source is applied to both ends of the RC loop to measure the loop resistance:

[0081] Xc=1 / (2πfC)

[0082] (U / I) 2 =R 2 +Xc 2 .

[0083] The board trigger capability test unit is used to test the trigger capability and receiving and sending status of the TCU board, the sending status of the TVM board and the trigger capability of the RPU board.

[0084] The test method of TCU board and RPU board is: whether the TCU board and RPU board can normally trigger the thyristor under test during the voltage drop test unit test is used to determine whether the RPU board functions normally;

[0085] The TVM board test method is: after loading 330V AC power supply voltage on the TVM board, whether the TVM board generates a return check signal is used to determine whether the function is normal.

[0086] like Figure 6 As shown, the thyristor tester for the converter valve of the present invention adopts a double-box structure, including a first box and a second box, the central processing unit, the switching unit and the blocking test unit are installed in the first box, the display interactive touch screen is installed in the box cover of the first box, the voltage drop test unit, the resistance-capacitance absorption test unit and the board triggering ability test unit are installed in the second box, the first box and the second box are connected by a panel-embedded multi-wire plug, and the test line is output from the first box.

[0087] The thyristor tester for the converter valve of the present invention has a reasonable structure and consists of four units: blocking test, voltage drop test, RC resistance-capacitance absorption test and board communication test. Each unit has clear functions and cooperates with each other, can effectively simulate actual working conditions, and comprehensively test key parameters of the thyristor.

[0088] The above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, a person skilled in the art can still modify or make equivalent substitutions to the specific implementations of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention are within the scope of protection of the claims of the present invention.

Claims

1. A thyristor tester for a converter valve, characterized in that: The invention comprises a display interactive touch screen, a central processing unit, a blocking test unit, a voltage drop test unit, a resistance-capacitance absorption test unit, a board triggering capability test unit and a switching unit. The blocking test unit, the voltage drop test unit, the resistance-capacitance absorption test unit and the board triggering capability test unit are all connected between the central processing unit and the switching unit, and the display interactive touch screen is connected to the central processing unit.

2. The thyristor tester for converter valve according to claim 1, characterized in that: The blocking test unit includes two parts: a DC test and a half-wave test. The DC test is configured as follows: Voltage adjustment range parameter V DC :Voltage range 1.00~5.00kV, resolution 0.01kV, accuracy ±3%; Current parameter I DC :Current range 1.0~100.0mA, resolution 0.1mA, accuracy ±3%±0.2mA; The half-wave test configuration is: Off-state and reverse peak voltage adjustment range parameter V DRM / V RRM :Voltage range 1.00~8.50kV, resolution 0.01kV, accuracy ±3%; Current parameter I DRM / I RRM :Current range 1.0~20.0mA, resolution 0.1mA, accuracy ±3%±0.2mA.

3. The thyristor tester for converter valve according to claim 1, characterized in that: The voltage drop test unit is configured as follows: Current parameter I: 3A, resolution 1A, accuracy ±3% ±0.2A; Voltage parameter range V: 0.50~5.00V, resolution 0.01V, accuracy ±3%±0.02V.

4. The thyristor tester for a converter valve according to claim 1, characterized in that: The RC absorption test unit is configured as follows: Resistance parameter R: 10.0~50.0Ω, resolution 0.1Ω, accuracy ±3%±0.5Ω; Capacitance parameters C: 1.00~5.00uF, resolution 0.01uF, accuracy ±3%±0.1uF.

5. The thyristor tester for converter valve according to claim 1, characterized in that: The board trigger capability test unit is used to detect the TCU board trigger capability and transceiver status, the TVM board sending status and the RPU board trigger capability.

6. The thyristor tester for converter valve according to claim 2, characterized in that: When the blocking test unit is in direct current test, the waveform is a direct current waveform, the voltage sampling point is at the position of 5ms, and the current sampling point is also at the position of 5ms; The DC test method of a single element is: start outputting from 0, increase the voltage incrementally at a speed of 3% of the set value, and detect the blocking condition; The DC test method of the valve assembly is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, maintain it for 200ms after the voltage reaches 1000V, detect the leakage current and calculate the current load resistance; then continue to increase the voltage, and the displayed leakage current becomes the sampling current-(voltage / load resistance); by default, the thyristor leakage current is very small at 1000V; compare the differences of each small valve group horizontally to find out the abnormal thyristor; When the blocking test unit performs a half-wave test, the waveform is a half-sine wave, the voltage sampling point is at the 5ms position, the current sampling point is also at the 5ms position, and the current protection point is between 0-5ms; The half-wave test method of a single element is: start the output from 0, increase the voltage incrementally at a speed of 3% of the set value, and detect the blocking condition.

7. The thyristor tester for converter valve according to claim 3, characterized in that: The voltage drop test unit uses a transformer as a pulse current source for test scheme 3A; The test method of the electric control valve body is as follows: provide energy to the TCU board through a 150V / 200W transformer, trigger the thyristor under test through the TCU board at a delay of 5ms after detecting the synchronous rising edge, sample the voltage drop multiple times 100us after triggering, sample the voltage when the 3A current is detected, and detect the feedback of the TCU board after completion. After judging the status of the board, measure the thyristor voltage drop; The test method of the light-controlled valve body is as follows: provide energy to the RPU board through a 150V / 200W transformer, and send out an optical signal through the RPU board after a 5ms delay after detecting the synchronous rising edge. After passing through the optical splitter, the light-controlled thyristor in the valve section is triggered. After the triggering, the voltage is sampled when the 3A current is detected. After completion, the feedback from the TVM board is detected, and the status of the TVM board is judged at the same time, completing the voltage drop test and board detection process at one time.

8. The thyristor tester for converter valve according to claim 4, characterized in that: The test method of the resistance-capacitance absorption test unit is: First, use a constant current source to charge the capacitor and measure the loop capacitance: I×ΔT=ΔV×C The two time intervals ΔT are known, the voltage is sampled twice at the corresponding two times to obtain ΔV, and the constant current I is also known. The size of the capacitor C is calculated according to the formula; Then, the CPU controls the high-frequency generator to emit a high-frequency sine wave, which is then passed through the signal amplifier to generate a high-frequency voltage source of a certain power, which is applied to both ends of the RC loop to measure the loop resistance: Xc=1 / (2πfC) (U / I) 2 =R 2 +Xc 2 。 9. The thyristor tester for converter valve according to claim 5, characterized in that: The test method of TCU board and RPU board is: whether the TCU board and RPU board can normally trigger the thyristor under test during the voltage drop test unit test is used to determine whether the RPU board functions normally; The TVM board test method is: after loading 330V AC power supply voltage on the TVM board, whether the TVM board generates a return check signal is used to determine whether the function is normal.

10. The thyristor tester for converter valve according to claim 1, characterized in that: It also includes a first box and a second box, the central processing unit, the switching unit and the blocking test unit are installed in the first box, the display interactive touch screen is installed in the box cover of the first box, the voltage drop test unit, the resistance-capacitance absorption test unit and the board triggering ability test unit are installed in the second box, the first box and the second box are connected through a panel-embedded multi-wire plug, and the test line is output from the first box.

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