Application and analysis on ±500kV line arrester in lighting protection of DC transmission line

Installing arresters is an important measure to improve the lighting withstand level of ±500kV DC transmission lines and to reduce the lighting flashover rate. Based on polymeric MOA with no-supporting series gap, arresters were used by a ±500kV DC transmission line, which were developed and manufactured by State Grid Electric Power Research Institute(SGEPRI). And the main properties of the arresters were discussed briefly, security risk, corona performance, arrester sheds and fittings corrosion after operating for a long time were analyzed from the perspective of reliability. At the same time, lighting trip-out failure of the ±500kV DC transmission line installing arresters and not was considering specially. The result shows that, frequent action for this kind of arresters didn´t appear in operation; it isn´t obvious to the corona performance of discharge electrode and fittings; the distribution of overhead line electrical field didn´t change apparently after installing arresters; according to the field monitoring, there is also no abnormal to the arresters external insulation and electrical connections; more than the thunderstorm season, there are no tripping accidents for ±500kV DC transmission line installing the arresters after operating for a long time, and compared with the previous year, the number of lightning trip is down to 0. So it is suggested that this type of arresters have favorable electrical and mechanical properties, and the lightning protection effect is significant, which may provide operating experience support for large-scale application of this type of arresters.