Flexible DC transmission project voltage source converter valve short circuit current test device

Abstract

The invention discloses a flexible DC transmission project voltage source converter valve short circuit current test device. Short circuit current branches are formed by an AC short circuit branch and a DC short circuit branch and are parallelly connected onto two ends of two sample valves respectively. Before the short circuit current test begins, a switch is used for selecting a sample valve for executing the short circuit current test, the sample valve and an assistant sample valve are triggered to be in a stable continuous operation state. Through a control strategy, the sample valve generates a short circuit current DC component through the DC short circuit branch. At a proper control point, a short circuit current AC component is introduced through the AC short circuit branch. The short circuit current DC component and the AC component are overlapped and then flow through the sample valve, and the required short circuit test current flows through the sample. The short circuit current equivalent to an actual fault working condition is adopted to check the short circuit current resisting ability of the sample valve, the DC short circuit current component and the AC short circuit current component are flexible and adjustable, the test capacity is large, and the test device is simple in structure and easy to build.

Description

Technical field: [0001] The invention belongs to the fields of flexible high-voltage direct current transmission, power electronics technology and user electric power technology, and in particular relates to a short-circuit current test device for a voltage source converter valve of a flexible direct current transmission project. Background technique: [0002] With the rapid development of flexible direct current transmission (VSC-HVDC) technology in my country and the construction of flexible direct current transmission projects, voltage source converter valves have been used more and more widely. It has high operating voltage, large conduction current and short circuit The characteristics of large capacity, its performance will directly affect the safe and reliable operation of the flexible direct current transmission system. Electrical test is an important means to evaluate the performance of voltage source converter valves. How to build a suitable electrical test circuit ...

AI Technical Summary

Problems solved by technology

[0004] Due to the limitation of capacitor bank capacity, equipment volume and grid short-circuit capacity, the short-circuit current amplitude of these two test methods cannot be very large

[0005] 1) The back-to-back short-circuit test device needs to use a large number of actual engineering valve groups to build a back-to-back test circuit. It is necessary to redesign other equipment parameters of the test device according to different engineering valve parameters. connected grid restrictions;

[0006] 2) The capacitor bank short-circuit current test device needs to invest a large number of capacitor banks to generate short-circuit current, and the short-circuit current generated by each capacitor bank needs to be accurately synchronized. The test device is bulky, the control system is complicated, and it is not easy to expand and upgrade

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