Novel thyristor-grade impedance testing device for direct-current converter valve

Abstract

The invention provides a novel realization method for testing thyristor-grade impedance. According to the method, the testing reliability, the testing precision and the testing efficiency can be improved effectively. By adopting the testing system, the direct-current voltage, and the alternating-current voltages of 100Hz and 10kHz are acted on the thyristor-grade sample; subsequently the thyristor-grade voltage and thyristor-grade current can be measured; the impedance is calculated; and the testing result can be transmitted to a controlling and displaying system by a CAN bus, thus facilitating the judgment on the testing results.

Description

technical field [0001] The invention relates to the field of power system devices, in particular to a novel thyristor-level impedance testing device for DC converter valves. Background technique [0002] As the most basic unit of the converter valve, the thyristor stage may encounter various operating conditions in the actual operation process. This experimental method simulates the three main operating conditions, and the influence of the external source of DC, power frequency and impact Thyristor stage damping loop parameters below. By using the impedance test system, apply DC, 100Hz, and 10kHz excitation sources to the thyristor-level test products, respectively test the thyristor-level impedance values ​​under these three sources, and compare with the calculated values. If it is within the required error range If within, the thyristor-level test product is considered qualified, otherwise it is considered unqualified. [0003] The thyristor-level circuit is the most bas...

AI Technical Summary

Problems solved by technology

The traditional test method for thyristor-level impedance is relatively simple, and most of them use multimeters, capacitor bridges, etc. to directly test the thyristor-level damping resistance, damping capacitance, DC voltage sharing resistance, etc.

This method is cumbersome, time-consuming, and inefficient to operate. Most importantly, this method cannot provide an excitation source and cannot reflect the working conditions of the thyristor stage during actual operation. This invention proposes a novel Using the bus method to achieve

[0005] Chinese patent application CN200910241741.8 discloses the use of impedance tester LCR unit to complete the measurement of damping resistance, damping capacitance value and DC voltage equalization resistance value. The measurement frequency is the method of frequency sweep, and the frequency range is 0-1MHz. The test results are communicated with the industrial computer through the GPIB bus, and the test results are displayed to the industrial computer. This test method relies on the impedance tester. Because in actual engineering, it is not necessary to clearly know the specific value of each component of the thyristor level. As long as you know whether the impedance is qualified or not, at the same time, due to the need to use an industrial computer to read the data, the volume, cost, and operation process of the system are too complicated

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