Reliability Assessment on Comment Electrode Sharing of ±800 kV UHV DC Project

Based on the series connection configuration of two 12-pulse converters in ±800 kV UHV DC links and reliability and availability figures of practical operation of HVDC links in China,the philosophy of reliability evaluation model of Xiangjiaba-Shanghai(i.e.XS800) UHV DC system was presented,also the reliability and availability was calculated and the reliability index was proposed based on the calculation result.Based on the model,the influence to XS800 HVDC link arise from sharing the comment electrode was also evaluated.