Test loop for voltage distribution non-uniform coefficient of high-voltage high-power resistor

Abstract

The test loop for the non-uniform voltage distribution coefficient of the high-voltage and high-power resistor provided by the utility model is used for solving the problem that the insulation margin of the existing high-voltage and high-power resistor is usually designed by adopting the conventional empirical data as the non-uniform voltage distribution coefficient of the high-voltage and high-power resistor; and the technical problem that the long-term safe operation of the high-voltage and high-power resistor has great uncertain factors is solved. The test loop for the voltage distribution non-uniform coefficient of the high-voltage high-power resistor provided by the utility model is provided with the impulse voltage generator, the first voltage measuring device and the plurality of second voltage measuring devices, and the impulse voltage is applied to the high-voltage high-power resistor through the impulse voltage generator; and when the impulse voltage is applied, the first voltage measuring device and the plurality of second voltage measuring devices are used for measuring the voltage at different positions of the high-voltage high-power resistor, so that the maximum non-uniform coefficient of the voltage distribution of the high-voltage high-power resistor under the transient voltage can be accurately obtained.

Description

Technical Field

[0001] This utility model relates to high-voltage, high-power resistors, and more particularly to a test circuit for the voltage distribution non-uniformity coefficient of high-voltage, high-power resistors. Background Technology

[0002] High-voltage, high-power resistors are widely used in flexible DC transmission due to their high energy absorption and insulation capabilities. However, due to the special structure of high-voltage, high-power resistors, there are certain parasitic inductances and stray capacitances inside. The presence of these parasitic inductances and stray capacitances causes the voltage distribution of the resistive elements inside the high-voltage, high-power resistor to have a large non-uniformity coefficient under transient voltage.

[0003] Because the insulation margin design of high-voltage, high-power resistors is closely related to their voltage distribution non-uniformity coefficient, and current insulation margin designs typically use empirical data as the voltage distribution non-uniformity coefficient, this method fails to obtain a true non-uniformity coefficient. This results in unreliable theoretical calculations of transient voltages, introducing significant uncertainties to the long-term safe operation of high-voltage, high-power resistors. Therefore, a reliable test circuit is needed to measure the voltage distribution non-uniformity coefficient, and the measurement results should serve as a valid basis for the insulation margin design of high-voltage, high-power resistors. Utility Model Content

[0004] The purpose of this invention is to address the technical problem that the insulation margin of existing high-voltage, high-power resistors is usually designed using past experience data as the voltage distribution non-uniformity coefficient, which leads to significant uncertainties in the long-term safe operation of high-voltage, high-power resistors. This invention provides a test circuit for the voltage distribution non-uniformity coefficient of high-voltage, high-power resistors.

[0005] To achieve the above objectives, the technical solution provided by this utility model is as follows:

[0006] A test circuit for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor, comprising N metal housings, where N≥2; each metal housing contains a first resistor unit, a second resistor unit, inductors L1 and L2, capacitors C1 and C2, and a first and a second outlet sleeve respectively located at both ends of the outer side of the metal housings; the first resistor unit, inductor L1, the second resistor unit, and inductor L2 are connected in series, with one end of the first resistor unit connected to the terminal block inside the first outlet sleeve, and the other end of inductor L2 connected to the terminal block inside the second outlet sleeve; one end of capacitor C1 is connected to the inner wall of the metal housing, and the other end is connected to the terminal block inside the first outlet sleeve; one end of capacitor C2 is connected to the inner wall of the metal housing, and the other end is connected to the terminal block inside the second outlet sleeve; its special feature is that it includes an impulse voltage generator, a first voltage measuring device, and 2N-1 second voltage measuring devices;

[0007] The output terminal of the impulse voltage generator is connected to the terminal block at the outer end of the first outgoing bushing on the first metal housing, and is used to apply the impulse voltage to the high-voltage, high-power resistor.

[0008] The input terminal of the first voltage measuring device is connected to the wiring terminal at the outer end of the first outgoing bushing on the first metal housing, and is used to measure the total voltage on the high-voltage, high-power resistor;

[0009] The input terminals of N of the 2N-1 second voltage measuring devices are respectively connected between the inductor L1 inside the N metal boxes and the second resistor unit. The input terminals of the remaining N-1 second voltage measuring devices are respectively connected to the wiring terminals at the outer end of the second outgoing sleeve on any of the first N-1 metal boxes.

[0010] The impulse voltage generator, the first voltage measuring device, and the second voltage measuring device are all grounded.

[0011] Furthermore, both the first voltage measuring device and the second voltage measuring device employ transient impulse voltage dividers.

[0012] Furthermore, the impulse voltage generator is a CDYH model impulse voltage generator.

[0013] The advantages of this utility model compared to the prior art are as follows:

[0014] This invention provides a test circuit for measuring the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor. An impulse voltage is applied to the high-voltage, high-power resistor using an impulse voltage generator. While the impulse voltage is applied, the voltage at different locations on the high-voltage, high-power resistor is measured using a first voltage measuring device and multiple second voltage measuring devices. This allows for the accurate determination of the maximum voltage distribution non-uniformity coefficient of each high-voltage, high-power resistor under transient voltage conditions, providing a good guarantee for the insulation margin design and subsequent safe operation of the high-voltage, high-power resistor. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of a test circuit embodiment of the present invention for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor.

[0016] The specific attached figures are labeled as follows:

[0017] 1-Metal housing; 2-First outgoing sleeve; 3-Second outgoing sleeve; 4-Impulse voltage generator; 5-First voltage measuring device; 6-Second voltage measuring device; 7-Wire; 8-First resistance unit; 9-Second resistance unit. Detailed Implementation

[0018] To make the advantages and features of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 As shown, a test circuit for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor includes an impulse voltage generator 4, a first voltage measuring device 5, and three second voltage measuring devices 6.

[0020] In this embodiment, the high-voltage, high-power resistor to be measured includes two metal housings 1, therefore, the number of second voltage measuring devices 6 is three. Each metal housing 1 is equipped with a first resistor unit 8, a second resistor unit 9, an inductor L1, an inductor L2, a capacitor C1, and a capacitor C2. A first lead-out sleeve 2 and a second lead-out sleeve 3 are respectively provided at both ends of the outer side of the metal housing 1. The first resistor unit 8, inductor L1, second resistor unit 9, and inductor L2 are connected in series. The other end of the first resistor unit 8 is connected to the terminal block inside the first lead-out sleeve 2 on the corresponding metal housing 1, and the other end of the inductor L2 is connected to the terminal block inside the second lead-out sleeve 3 on the corresponding metal housing 1. One end of the capacitor C1 is connected to the inner wall of the metal housing 1, and the other end is connected to the terminal block inside the first lead-out sleeve 2. One end of the capacitor C2 is connected to the inner wall of the metal housing 1, and the other end is connected to the terminal block inside the second lead-out sleeve 3.

[0021] The terminal block at the outer end of the second outgoing sleeve 3 on the first metal enclosure 1 is connected to the terminal block at the outer end of the second outgoing sleeve 3 on the second metal enclosure 1 via a wire 7. The terminal block at the outer end of the first outgoing sleeve 2 on the second metal enclosure 1 is grounded. The wire 7 between the first metal enclosure 1 and the second metal enclosure 1, and the two metal enclosures 1 are respectively grounded through a grounding capacitor C3.

[0022] The impulse voltage generator 4 is used to output lightning impulse voltage waveforms, operational impulse voltage waveforms, or other types of impulse voltage waveforms. The output terminal of the impulse voltage generator 4 is connected to the terminal block at the outer end of the first outgoing bushing 2 on the first metal housing 1, and is used to apply the impulse voltage to the high-voltage, high-power resistor through the terminal block at the outer end of the first outgoing bushing 2 on the first metal housing 1. The peak voltage output of the impulse voltage generator 4 depends on the inter-terminal insulation level of the high-voltage, high-power resistor. In this embodiment, the impulse voltage generator 4 is a CDYH model impulse voltage generator with a voltage range of 300kV to 4000kV.

[0023] The input terminal of the first voltage measuring device 5 is connected to the terminal block at the outer end of the first outgoing sleeve 2 on the first metal housing 1, and is used to measure the total voltage applied to the high-voltage, high-power resistor.

[0024] The input terminal of the first second voltage measuring device 6 is connected between the inductor L1 and the second resistor unit 9 inside the first metal housing 1, i.e., position ① in the figure. The input terminal of the second second voltage measuring device 6 is connected between the inductor L1 and the second resistor unit 9 inside the second metal housing 1, i.e., position ② in the figure. The input terminal of the third second voltage measuring device 6 is connected to the terminal block at the outer end of the second outgoing sleeve 3 on the first metal housing 1, i.e., position ③ in the figure. These devices are used to measure the voltage at different positions on the high-voltage, high-power resistor.

[0025] In this embodiment, both the first voltage measuring device 5 and the second voltage measuring device 6 preferably employ transient impulse voltage dividers, and their measurement range is determined based on the impulse voltage level of the high-voltage, high-power resistor. The impulse voltage generator 4, the first voltage measuring device 5, and the three second voltage measuring devices 6 are all grounded.

[0026] Since the capacitors C1, C2, and grounding capacitor C3 within each metal housing 1 of the high-voltage, high-power resistor are stray capacitors, and the inductors L1 and L2 are parasitic inductors, they will significantly affect the voltage distribution of the high-voltage, high-power resistor under transient conditions. Therefore, the voltage distribution non-uniformity coefficient of the high-voltage, high-power resistor in this embodiment is determined using the test circuit of this invention. The specific measurement process is as follows:

[0027] Three impulse voltages are applied to a high-voltage, high-power resistor using an impulse voltage generator 4. The peak voltage values ​​measured by the first voltage measuring device 5 and the three second voltage measuring devices 6 are recorded for each impulse voltage application. The three peak voltage values ​​measured by the first voltage measuring device 5 are denoted as U1-1, U1-2, and U1-3, respectively; the three peak voltage values ​​measured by the first second voltage measuring device 6 are denoted as U2-1, U2-2, and U2-3, respectively; the three peak voltage values ​​measured by the second second voltage measuring device 6 are denoted as U3-1, U3-2, and U3-3, respectively; and the three peak voltage values ​​measured by the third second voltage measuring device 6 are denoted as U4-1, U4-2, and U4-3, respectively. The average of the three measurement data from the first voltage measuring device 5 and the three second voltage measuring devices 6 is taken to obtain UO, U1, U2, and U3, respectively. The measured voltages of the first resistor unit 8 and the second resistor unit 9 in the first metal housing 1, and the first resistor unit 8 and the second resistor unit 9 in the second metal housing 1, are UO-U1, U1-U2, U2-U3, and U3, respectively. Therefore, the non-uniformity coefficients of the first resistor unit 8 and the second resistor unit 9 in the first metal housing 1, and the first resistor unit 8 and the second resistor unit 9 in the second metal housing 1, are (UO-U1) / UO / 4, (U1-U2) / UO / 4, (U2-U3) / UO / 4, and U3 / UO / 4, respectively. The maximum value among the four non-uniformity coefficients is selected as the maximum non-uniformity coefficient of each high-voltage, high-power resistor, which is used for the insulation margin design of the high-voltage, high-power resistor.

[0028] The above description is only used to illustrate the technical solution of this utility model, and is not intended to limit it. For those skilled in the art, modifications can be made to the specific technical solutions described in the above embodiments, or equivalent substitutions can be made to some of the technical features. However, these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions protected by this utility model.

Claims

1. A test circuit for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor, wherein the high-voltage, high-power resistor comprises N metal housings (1), N≥2; a first resistor unit (8), a second resistor unit (9), an inductor L1, an inductor L2, a capacitor C1, and a capacitor C2 are provided inside the metal housings (1), and a first outlet sleeve (2) and a second outlet sleeve (3) are respectively provided at both ends of the outer side of the metal housings (1); the first resistor unit (8), the inductor L1, the second resistor unit (9), and the inductor L2 are connected in series, the other end of the first resistor unit (8) is connected to the terminal block inside the first outlet sleeve (2), and the other end of the inductor L2 is connected to the terminal block inside the second outlet sleeve (3); one end of the capacitor C1 is connected to the inner wall of the metal housing (1), and the other end is connected to the terminal block inside the first outlet sleeve (2), and one end of the capacitor C2 is connected to the inner wall of the metal housing (1), and the other end is connected to the terminal block inside the second outlet sleeve (3); characterized in that: It includes an impulse voltage generator (4), a first voltage measuring device (5), and 2N-1 second voltage measuring devices (6); The output terminal of the impulse voltage generator (4) is connected to the terminal block at the outer end of the first outgoing sleeve (2) on the first metal housing (1) to apply the impulse voltage to the high-voltage high-power resistor. The input terminal of the first voltage measuring device (5) is connected to the terminal block at the outer end of the first outgoing sleeve (2) on the first metal housing (1) to measure the total voltage on the high voltage high power resistor; The input terminals of N of the 2N-1 second voltage measuring devices (6) are respectively connected between the inductor L1 and the second resistor unit (9) inside the N metal boxes (1), and the input terminals of the remaining N-1 second voltage measuring devices (6) are respectively connected to the wiring terminals at the outer end of the second outgoing sleeve (3) on the first N-1 metal boxes (1); The impulse voltage generator (4), the first voltage measuring device (5), and the second voltage measuring device (6) are all grounded.

2. The test circuit for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor according to claim 1, characterized in that: Both the first voltage measuring device (5) and the second voltage measuring device (6) adopt transient impulse voltage dividers.

3. The test circuit for the voltage distribution non-uniformity coefficient of a high-voltage, high-power resistor according to claim 2, characterized in that: The impulse voltage generator (4) is a CDYH-type impulse voltage generator.

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