Study on Fast Analytic Method of Sending-side Wind-turbine Generator Overvoltage under Power Disturbance of Large Capacity HVDC

In recent years, with the rapid development of UHV technology and renewble energy generation, when serious power disturbances occur in the large-capacity HVDC, the wind turbine generator (WTG) in sending systems will be sufferred serious transient overvoltage, which results in large-scale WTG overvoltage tripping. To this problem, the mechanism of WTG transient overvoltage resulted by HVDC large power disturbance was analyzed, a fast analytic method of converter station and WTG overvoltage was proposed, the complete differential sensitivity formula of bus voltage variation due to bus load variation was derived. The results were verified in The Jiuquan-Hunan HVDC with its sending-side AC system. The results show that the proposed method has better engineering applicability and it can be adopted to assess the risk of WTG overvoltage tripping.