±660kV宁东—山东直流输电换流阀最小交流电压运行试验的关键应力

Key Stresses in Minimum AC Voltage Operational Tests of Thyristor Valves for ±660 kV HVDC Transmission Project From Ningdong to Shandong

首先介绍了直流换流阀基本结构与运行特性,分析了换流阀在最小交流电压条件下开通、关断的暂态过程,指出了影响直流换流阀可靠运行的因素,在此基础上总结了最小交流电压运行试验的关键应力,为合成试验装置输出提供了依据。最后通过宁东—山东±660 kV直流换流阀最小交流电压运行试验结果,验证了以关键应力为依据、以合成方法进行的最小交流电压运行试验经济实用、充分等效,能够满足工程要求。

As a part of DC valve operational tests, the minimum AC voltage operation tests aims at examining the firing and extinction characteristics of converter valves under low AC voltage at valve side, so special requirement are put forward to testing devices. To implement test test purposes, it is the key to put forward concrete requirements to testing devices in the viewpoint of equivalence, and its presupposition is to determine the needed key stresses. Firstly, the basic structure an operational characteristic of DC converter valves are presented, and the transient processes of firing and extincting the converter valves under minimum AC voltage are analyzed; then the factors impacting the reliable operation of DC converter valves are pointed out and on this basis the key stresses under minimum AC voltage operational tests are summarized to provide the foundation for the synthesis of testing devices; finally, the results of minimum AC voltage operational tests of DC converter valves for ±660kV transmission project from Ningdong to Shandong are given. It is verified by the results that the minimum AC voltage operational tests, which is based on the key stresses and performed by synthetical method, can be fully equivalent to actual system and meet engineering demands, and it is economical and practicabel.