Chain Static Synchronous Compensator Igct Valve Test Method

The rapid development of power electronics has led to extensive application of power electronics facility in power system. To advance the industrialization of those facilities, the system operating reliability and stability must be insured. So it is necessary for the manufacturers to perform strict and comprehensive acceptance&type tests before the facility is put into operation.Static synchronous Var compensator (STATCOM) is an important member of Flexible AC Transmission System (FACTS) family. Tsinghua University and XuJi Group are developping conjointly a STATCOM with the novel topology of chain circuit. With the background of this engineering, the thesis applies to develop a reasonable test procedure to verify capability of the IGCT valve withstanding the voltage, current and thermal stresses. But the high ratings of the facility make it almost impossible to test the equipment in the real system directly. Thus the equivalent test method must be adopted. The core of the equivalence analyses is finding an alternative test method and accordingly the right test parameter to reproduce the stresses applied on the valves, which are equivalent with that in the real conditions by effect.The equivalence analyses should be based on the understanding of the principle and characteristic of the device. This thesis firstly elaborates the voltage and current stresses of the IGCT valve during steady and transient states. Following, the test purpose, items and equivalent demands are proposed. On the bases of the foregoing work, the test circuit, controlling method and mathematic model are brought forward, the main parameters are concluded, and thus a detailed and comprehensive test scheme is formed.In order to analyze the stresses of the valve and verified the equivalence of the test, substantial simulations were done with EMTDC (some with Saber). Still Further, some tests had also been implemented according to the test scheme proposed, the result of which got to the identical results with the former analyses and simulations, proving the test scheme is right and viable.