A test circuit and device for thyristor voltage monitoring board

Abstract

The present invention discloses a test circuit of a thyristor voltage monitoring board, comprising: a thyristor voltage monitoring board, a high-voltage power supply, a protective resistor, an inductor, a damping resistor, a damping capacitor, a photoelectric conversion board and an oscilloscope. The damping resistor is connected in series with the damping capacitor to form a damping branch, the inductor forms an inductance branch connected in parallel with the damping branch, and the high-voltage power supply is connected in series with the protective resistor and then the damping branch and the inductance branch are connected. The X1 end of the thyristor voltage monitoring board is connected to the midpoint of the damping branch, the X2 end is connected to the protective resistor, the X3 and X4 ends are grounded, and the optical fiber interface C is connected to the optical signal receiving end of the photoelectric conversion board. The CH1 channel of the oscilloscope is connected to the protective resistor, and the CH2 channel is connected to the electrical signal sending end of the photoelectric conversion board. By adopting the embodiment of the present invention, the performance requirements of the test circuit of the thyristor voltage monitoring board on the high-voltage power supply can be effectively reduced, the difficulty of constructing the test circuit can be reduced, and the feasibility of conducting tests in the laboratory can be improved.

Description

Technical Field

[0001] The invention relates to the field of electric power technology, and in particular to a test circuit and a device for a thyristor voltage monitoring board. Background Art

[0002] With the rapid development of power transmission technology, high-voltage thyristor valves are widely used as basic converter units in UHV DC transmission projects. Thyristor valves are converter units composed of thyristors in series and parallel. The safety, reliability and consistency of the trigger signal of each thyristor will affect the working stability of the thyristor valve. Therefore, in order to ensure the safe and reliable operation of the converter valve, each thyristor in the converter valve is equipped with a thyristor voltage monitoring (TVM) board. On the one hand, the TVM board is responsible for the DC voltage equalization of the thyristor, and on the other hand, it detects the voltage at both ends of the thyristor and generates relevant feedback signals to analyze whether the thyristor is faulty.

[0003] If the TVM board does not work properly, it will affect the control safety of the thyristor. Therefore, before it is put into use, the voltage detection function of each TVM board must be fully tested. In the prior art, the feedback signal sent by the TVM board is detected by the thyristor voltage monitoring board test circuit to determine whether the function of the TVM board is normal. However, in the process of implementing the present invention, the inventors found that the prior art has at least the following problems: the existing thyristor voltage detection board test circuit has high requirements on the performance of the high-voltage power supply, and the high-voltage power supply of a general laboratory is difficult to meet the requirements of the test circuit. The cost of purchasing a suitable high-voltage power supply is relatively high; cooperation with manufacturers or laboratories with suitable power supplies requires compliance with the other party's production or research plan arrangements, which is not conducive to carrying out systematic testing. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to provide a test circuit and device for a thyristor voltage monitoring board, which can effectively reduce the performance requirements for a high voltage power supply and greatly reduce the difficulty of performing functional testing on the thyristor voltage monitoring board.

[0005] To achieve the above object, an embodiment of the present invention provides a test circuit of a thyristor voltage monitoring board, comprising: a thyristor voltage monitoring board, a high voltage power supply, a protection resistor, an inductor, a damping resistor, a damping capacitor, a photoelectric conversion board and an oscilloscope; the thyristor voltage monitoring board is provided with electrical ports X1, X2, X3, X4 and an optical fiber interface C;

[0006] The positive electrode of the high-voltage power supply is connected to the first end of the protection resistor, and the negative electrode of the high-voltage power supply is grounded; the second end of the protection resistor is connected to the first end of the inductor, and the second end of the inductor is connected to the negative electrode of the high-voltage power supply; the first end of the damping resistor is connected to the first end of the inductor, the second end of the damping resistor is connected to the first end of the damping capacitor, and the second end of the damping capacitor is connected to the second end of the inductor;

[0007] The electrical port X1 of the thyristor voltage monitoring board is connected to the second end of the damping resistor, the electrical port X2 of the thyristor voltage monitoring board is connected to the second end of the protection resistor, and the electrical ports X3 and X4 of the thyristor voltage monitoring board are grounded; the optical fiber interface C of the thyristor voltage monitoring board is connected to the optical signal receiving end of the photoelectric conversion board;

[0008] The CH1 channel of the oscilloscope is connected to the second end of the protection resistor, and the CH2 channel of the oscilloscope is connected to the electrical signal sending end of the photoelectric conversion board.

[0009] Compared with the prior art, the test circuit of a thyristor voltage monitoring board disclosed in the present invention reduces the power supply current by connecting an inductor in parallel on the damping branch, thereby solving the problem in the prior art that the current requirement for the high-voltage power supply is high, resulting in great difficulty in carrying out functional testing of the thyristor voltage monitoring board. The test circuit of the thyristor voltage monitoring board effectively reduces the performance requirement of the high-voltage power supply for the test circuit, reduces the difficulty of constructing the test circuit, and improves the feasibility of conducting tests in the laboratory.

[0010] As an improvement of the above solution, the test circuit of the thyristor voltage monitoring board further includes a constant temperature and humidity test chamber;

[0011] The thyristor voltage monitoring board is arranged in the constant temperature and humidity test box.

[0012] As an improvement of the above solution, the constant temperature and humidity test box is provided with reserved holes; the electrical ports X1, X2, X3, X4 and the optical fiber interface C on the thyristor voltage monitoring board are connected to the external circuit through the reserved holes of the constant temperature and humidity test box.

[0013] Compared with the prior art, the test circuit of a thyristor voltage monitoring board disclosed in the present invention controls the operating environment of the thyristor voltage monitoring board by adding a constant temperature and humidity test chamber, making the test environment more in line with actual operating conditions, expanding the applicability of the test circuit, and thus improving the reliability and accuracy of the functional test results of the thyristor voltage monitoring board.

[0014] As an improvement of the above solution, the test circuit of the thyristor voltage monitoring board also includes a multimeter and a voltage-equalizing resistor;

[0015] The voltage-equalizing resistor is installed on the thyristor voltage monitoring board, the first measurement node of the voltage-equalizing resistor is connected to the red test lead of the multimeter, and the second measurement node of the voltage-equalizing resistor is connected to the black test lead of the multimeter.

[0016] As an improvement of the above solution, the first measurement node and the second measurement node of the voltage-equalizing resistor are connected to the multimeter via a silicone high-voltage wire.

[0017] Compared with the prior art, the test circuit of a thyristor voltage monitoring board disclosed in the present invention evaluates the surface insulation condition of the thyristor voltage monitoring board by detecting the surface insulation resistance of the thyristor voltage monitoring board, which is beneficial to analyzing the functional failure mechanism of the thyristor voltage monitoring board and further improving the safety and stability of the thyristor voltage monitoring board.

[0018] As an improvement of the above solution, the voltage amplitude of the high voltage power supply is 8kV.

[0019] As an improvement of the above solution, the inductance value of the inductor is 7.24H.

[0020] As an improvement of the above solution, the resistance of the protection resistor is 2.5 kΩ to 7.5 kΩ.

[0021] As an improvement of the above solution, the resistance of the protection resistor is 5 kΩ.

[0022] An embodiment of the present invention further provides a test device for a thyristor voltage monitoring board, comprising a test circuit for a thyristor voltage monitoring board as described in any one of the above items. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of a test circuit of a thyristor voltage monitoring board provided in Embodiment 1 of the present invention;

[0024] Figure 2 It is a structural schematic diagram of a test circuit of a thyristor voltage monitoring board provided in the second embodiment of the present invention;

[0025] Figure 3 It is a structural schematic diagram of a test circuit of a thyristor voltage monitoring board provided in Embodiment 3 of the present invention;

[0026] Figure 4 It is a partial connection diagram of the thyristor voltage monitoring board and the multimeter in the third embodiment of the present invention;

[0027] In the figure: 1-thyristor voltage monitoring board, 2-high voltage power supply, 3-protection resistor, 4-inductor, 5-damping resistor, 6-damping capacitor, 7-photoelectric conversion board, 8-oscilloscope, 9-constant temperature and humidity test chamber, 10-multimeter, 11-equalizing resistor, 12-silicone high voltage wire. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Embodiment 1

[0030] See also Figure 1 , is a schematic diagram of the structure of the test circuit of the thyristor voltage monitoring board provided in the first embodiment of the present invention. A test circuit of a thyristor voltage monitoring board provided in the first embodiment of the present invention comprises a thyristor voltage monitoring board 1, a high voltage power supply 2, a protection resistor 3, an inductor 4, a damping resistor 5, a damping capacitor 6, a photoelectric conversion board 7 and an oscilloscope 8. The thyristor voltage monitoring board 1 is provided with electrical ports X1, X2, X3, X4 and an optical fiber interface C.

[0031] The positive electrode of the high-voltage power supply 2 is connected to the first end of the protection resistor 3, and the negative electrode of the high-voltage power supply 2 is grounded; the second end of the protection resistor 3 is connected to the first end of the inductor 4, and the second end of the inductor 4 is connected to the negative electrode of the high-voltage power supply 2; the first end of the damping resistor 5 is connected to the first end of the inductor 4, the second end of the damping resistor 5 is connected to the first end of the damping capacitor 6, and the second end of the damping capacitor 6 is connected to the second end of the inductor 4. The electrical port X1 of the thyristor voltage monitoring board 1 is connected to the second end of the damping resistor 5, the electrical port X2 of the thyristor voltage monitoring board 1 is connected to the second end of the protection resistor 3, and the electrical ports X3 and X4 of the thyristor voltage monitoring board 1 are grounded; the optical fiber interface C of the thyristor voltage monitoring board 1 is connected to the optical signal receiving end of the photoelectric conversion board 7. The CH1 channel of the oscilloscope 8 is connected to the second end of the protection resistor 3, and the CH2 channel of the oscilloscope 8 is connected to the electrical signal sending end of the photoelectric conversion board 7.

[0032] Specifically, the high-voltage power supply 2 is used to provide the energy required by the test circuit of the thyristor voltage monitoring board during operation, simulating the high-voltage working conditions of the thyristor voltage monitoring board during operation. In an embodiment of the present invention, in order to test the overvoltage detection function of the thyristor voltage monitoring board 1, the voltage amplitude of the high-voltage power supply 2 needs to reach 8kV. The protective resistor 3 mainly plays a role in current limiting, preventing excessive current in the circuit from damaging the equipment. The high-voltage power supply 2 and the protective resistor 3 are connected in series to ensure the safe operation of the test circuit of the thyristor voltage monitoring board.

[0033] The resistance value of the protection resistor can be set and adjusted according to the actual operation of the test circuit of the thyristor voltage monitoring board. As a preferred embodiment, the resistance value of the protection resistor is 2.5 kΩ to 7.5 kΩ.

[0034] As a more preferred implementation, the resistance of the protection resistor is 5 kΩ.

[0035] Furthermore, the damping resistor 5 and the damping capacitor 6 are connected in series to form a damping branch. The inductor 4 forms an inductor branch and is connected in parallel with the damping branch. The high-voltage power supply 2 and the protective resistor 3 are connected in series and then connected in parallel with the damping branch. The damping branch is used to simulate the electrical environment in which the thyristor voltage monitoring board 1 works. The damping resistor 5 and the damping capacitor 6 are consistent with the structure when the thyristor is actually running, and play a role in voltage balancing during the opening and closing of the thyristor. Among them, the resistance value of the damping resistor 5 is 36Ω, and the capacitance value of the damping capacitor is 1.4μF.

[0036] The port X2 of the thyristor voltage monitoring board 1 is connected to the positive electrode of the high voltage power supply 2, and the ports X3 and X4 are connected to the negative electrode of the high voltage power supply 2; the port X1 of the thyristor voltage monitoring board 1 is connected in parallel between the damping resistor 5 and the damping capacitor 6 in the damping branch. Then, by connecting the photoelectric conversion board 7 and the oscilloscope 8, the test circuit of the thyristor voltage monitoring board is formed.

[0037] During the operation of the thyristor voltage monitoring board 1, the high-voltage power supply 2 provides energy for the test circuit, the photoelectric conversion board 7 converts the optical pulse signal from the thyristor voltage monitoring board 1 into an electrical signal and sends it to the oscilloscope 8. The oscilloscope 8 monitors the power signal of the high-voltage power supply 2 through the CH1 channel and monitors the electrical signal converted by the photoelectric conversion board 7 through the CH2 channel, thereby judging the functional status of the thyristor voltage monitoring board and realizing the analysis of the overvoltage monitoring function of the thyristor voltage monitoring board 1.

[0038] In the application process of the test circuit of the thyristor voltage monitoring board, since the voltage amplitude of the high-voltage power supply is 8kV, and the impedance of the damping branch is about 2274Ω, without the inductor 4 connected in parallel, the power supply current needs to reach 3.5A, and the power supply performance requirements of the high-voltage power supply 2 are too high. The high-voltage power supply of a general laboratory is difficult to meet the requirements of the test circuit, resulting in greater difficulty in carrying out functional testing of the thyristor voltage monitoring board. To solve the above problem, the embodiment of the present invention increases the impedance of the main circuit by connecting the inductor 4 in parallel at both ends of the damping branch, thereby reducing the current demand of the high-voltage power supply and reducing the performance requirements for the high-voltage power supply.

[0039] Furthermore, the inductance value of the inductor 4 is determined according to the capacitance value of the damping capacitor 6 in the damping branch. As a preferred embodiment, the inductance value of the inductor 4 is 7.24H. By connecting the inductor 4 in parallel, the impedance of the main circuit can be increased to 143.6kΩ, so that the power supply current only needs to reach 0.056A to meet the working requirements of the test circuit of the thyristor voltage monitoring board. The high-voltage power supply of a general laboratory can meet the requirements of the test circuit of the thyristor voltage monitoring board, which greatly reduces the performance requirements for the high-voltage power supply 2 and greatly reduces the difficulty of carrying out functional testing of the thyristor voltage monitoring board.

[0040] Embodiment 1 of the present invention provides a test circuit for a thyristor voltage monitoring board. By connecting an inductor in parallel to a damping branch, the power supply current is reduced, thereby solving the problem in the prior art that the current requirement for the high-voltage power supply is high, resulting in great difficulty in carrying out functional testing of the thyristor voltage monitoring board. The test circuit of the thyristor voltage monitoring board is effectively reduced in terms of the performance requirement for the high-voltage power supply, the difficulty in constructing the test circuit is reduced, and the feasibility of conducting tests in the laboratory is improved.

[0041] Embodiment 2

[0042] As a preferred embodiment, see Figure 2 , is a schematic diagram of the structure of the test circuit of the thyristor voltage monitoring board provided in the second embodiment of the present invention. The second embodiment of the present invention is implemented on the basis of the first embodiment, and the test circuit of the thyristor voltage monitoring board also includes a constant temperature and humidity test box 9. The thyristor voltage monitoring board 1 is arranged in the constant temperature and humidity test box 9. The constant temperature and humidity test box 9 is used to control the test environment of the test circuit of the thyristor voltage monitoring board.

[0043] Furthermore, the constant temperature and humidity test box 9 is provided with reserved holes; the electrical ports X1, X2, X3, X4 and the optical fiber interface C on the thyristor voltage monitoring board 1 are connected to the external circuit through the reserved holes of the constant temperature and humidity test box 9.

[0044] In actual projects, the working environment conditions of the thyristor voltage monitoring board 1 are relatively complex. For example, under normal operating conditions, the ambient humidity is usually below 55% RH, while during the commissioning process, the ambient humidity usually reaches 70% RH. At the same time, the ambient temperature and humidity in different regions are also different. The existing thyristor voltage monitoring board test circuit usually carries out functional tests in a natural environment, which is quite different from the actual operating conditions of the thyristor voltage monitoring board, resulting in functional test results of the thyristor voltage monitoring board being different from the actual operating conditions. In addition, the test results of different manufacturers and laboratories may also have different test results due to different test environments, which seriously affects the accuracy of the functional detection of the thyristor voltage monitoring board.

[0045] To solve the above problems, in an embodiment of the present invention, the constant temperature and humidity test box 9 is arranged on the test circuit of the thyristor voltage monitoring board, and the thyristor voltage monitoring board 1 is placed in the constant temperature and humidity test box 9. The electrical ports X1, X2, X3, X4 and the optical fiber interface C on the thyristor voltage monitoring board 1 are connected to the external circuit through the reserved holes of the constant temperature and humidity test box 9. By adjusting the temperature and humidity of the constant temperature and humidity test box 9, the test environment of the test circuit of the thyristor voltage monitoring board is controlled, so that the operating environment of the thyristor voltage monitoring board 1 can be simulated according to actual conditions.

[0046] Embodiment 2 of the present invention provides a test circuit for a thyristor voltage monitoring board. By adding a constant temperature and humidity test chamber to control the operating environment of the thyristor voltage monitoring board, the test environment is made more in line with actual operating conditions, the applicability of the test circuit is expanded, and the reliability and accuracy of the functional test results of the thyristor voltage monitoring board are improved.

[0047] Embodiment 3

[0048] As a preferred embodiment, see Figure 3 , is a schematic diagram of the structure of the test circuit of the thyristor voltage monitoring board provided in the third embodiment of the present invention. The third embodiment of the present invention is implemented on the basis of the first embodiment or the second embodiment, and the test circuit of the thyristor voltage monitoring board also includes a multimeter 10. The multimeter 10 is connected to the thyristor voltage monitoring board 1 and is used to monitor the surface insulation of the thyristor voltage detection board 1.

[0049] The existing thyristor voltage monitoring board test circuit can only determine whether the function of the thyristor voltage monitoring board 1 is normal, but cannot reflect the cause of the abnormal function of the thyristor voltage monitoring board 1, and cannot reflect the internal mechanism of the functional problem of the thyristor voltage monitoring board 1, which is not conducive to further improvement and research on the thyristor voltage monitoring board.

[0050] To solve the above problem, in an embodiment of the present invention, the multimeter 10 is arranged on the test circuit of the thyristor voltage monitoring board, and the functional failure mechanism of the thyristor voltage detection board 1 is further analyzed by monitoring the surface insulation of the thyristor voltage detection board 1.

[0051] As a preferred embodiment, see Figure 4, is a partial connection diagram of the thyristor voltage monitoring board and the multimeter in the third embodiment of the present invention. The test circuit of the thyristor voltage monitoring board also includes a voltage-equalizing resistor 11, which is installed on the thyristor voltage monitoring board 1, and the first measurement node of the voltage-equalizing resistor 11 is connected to the red test lead 101 of the multimeter 10, and the second measurement node of the voltage-equalizing resistor 11 is connected to the black test lead 102 of the multimeter 10.

[0052] Preferably, the first measurement node of the voltage-equalizing resistor 11 is connected to the red test lead 101 of the multimeter 10 through a silicone high-voltage wire 12 ; the second measurement node of the voltage-equalizing resistor 11 is connected to the black test lead 102 of the multimeter 10 through a silicone high-voltage wire 12 .

[0053] The deterioration of the surface insulation of the thyristor voltage monitoring board is one of the reasons leading to its functional failure. In the embodiment of the present invention, a multimeter 10 is used in the test circuit of the thyristor voltage monitoring board to measure the resistance of the grading resistor 11 on the surface of the thyristor voltage monitoring board 1 in real time. The decrease in the resistance value reflects the decrease in the surface insulation performance of the thyristor voltage monitoring board 1. Combined with the functional test results, the failure mechanism of the thyristor voltage monitoring board is analyzed to further improve the safety and stability of the thyristor voltage monitoring board.

[0054] Embodiment 3 of the present invention provides a test circuit for a thyristor voltage monitoring board, which uses a multimeter to detect the surface insulation resistance of the thyristor voltage monitoring board to evaluate the surface insulation condition of the thyristor voltage monitoring board, which is beneficial to analyzing the functional failure mechanism of the thyristor voltage monitoring board and further improving the safety and stability of the thyristor voltage monitoring board.

[0055] Embodiment 4

[0056] Embodiment 4 of the present invention further provides a test device for a thyristor voltage monitoring board, and the test device for the thyristor voltage monitoring board includes the test circuit of the thyristor voltage monitoring board as described in any one of the above embodiments 1 to 3. The test device for the thyristor voltage monitoring board includes all the structural components, working principles and beneficial effects of the test circuit of the thyristor voltage monitoring board, which will not be described in detail here.

[0057] The above is a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements and modifications without departing from the principle of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A test circuit for a thyristor voltage monitoring board, characterized in that: include: Thyristor voltage monitoring board, high voltage power supply, protection resistor, inductor, damping resistor, damping capacitor, photoelectric conversion board and oscilloscope; The thyristor voltage monitoring board is provided with electrical ports X1, X2, X3, X4 and an optical fiber interface C; The positive electrode of the high-voltage power supply is connected to the first end of the protection resistor, and the negative electrode of the high-voltage power supply is grounded; the second end of the protection resistor is connected to the first end of the inductor, and the second end of the inductor is connected to the negative electrode of the high-voltage power supply; the first end of the damping resistor is connected to the first end of the inductor, the second end of the damping resistor is connected to the first end of the damping capacitor, and the second end of the damping capacitor is connected to the second end of the inductor; The electrical port X1 of the thyristor voltage monitoring board is connected to the second end of the damping resistor, the electrical port X2 of the thyristor voltage monitoring board is connected to the second end of the protection resistor, and the electrical ports X3 and X4 of the thyristor voltage monitoring board are grounded; the optical fiber interface C of the thyristor voltage monitoring board is connected to the optical signal receiving end of the photoelectric conversion board; The CH1 channel of the oscilloscope is connected to the second end of the protection resistor, and the CH2 channel of the oscilloscope is connected to the electrical signal sending end of the photoelectric conversion board.

2. The test circuit of the thyristor voltage monitoring board according to claim 1, characterized in that: The test circuit of the thyristor voltage monitoring board also includes a constant temperature and humidity test chamber; The thyristor voltage monitoring board is arranged in the constant temperature and humidity test box.

3. The test circuit of the thyristor voltage monitoring board according to claim 2, characterized in that: The constant temperature and humidity test box is provided with reserved holes; the electrical ports X1, X2, X3, X4 and the optical fiber interface C on the thyristor voltage monitoring board are connected to the external circuit through the reserved holes of the constant temperature and humidity test box.

4. The test circuit of the thyristor voltage monitoring board according to claim 1, characterized in that: The test circuit of the thyristor voltage monitoring board also includes a multimeter and a voltage-equalizing resistor; The voltage-equalizing resistor is installed on the thyristor voltage monitoring board, the first measurement node of the voltage-equalizing resistor is connected to the red test lead of the multimeter, and the second measurement node of the voltage-equalizing resistor is connected to the black test lead of the multimeter.

5. The test circuit of the thyristor voltage monitoring board according to claim 4, characterized in that: The first measurement node and the second measurement node of the voltage-equalizing resistor are connected to the multimeter through a silicone high-voltage wire.

6. The test circuit of the thyristor voltage monitoring board according to claim 1, characterized in that: The voltage amplitude of the high voltage power supply is 8 kV.

7. The test circuit of the thyristor voltage monitoring board according to claim 1, characterized in that: The inductance value of the inductor is 7.24H.

8. The test circuit of the thyristor voltage monitoring board according to claim 1, characterized in that: The resistance of the protection resistor is 2.5 kΩ to 7.5 kΩ.

9. The test circuit of the thyristor voltage monitoring board according to claim 8, characterized in that: The resistance of the protection resistor is 5 kΩ.

10. A test device for a thyristor voltage monitoring board, characterized in that: A test circuit comprising a thyristor voltage monitoring board as claimed in any one of claims 1 to 9.

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