Study on lightning overvoltage and commutation failure in UHV AC/DC hybrid system

Abstract

Due to the high UHV AC/DC transmission line tower, the working voltage amplitude on the wire is large, causing lightning accidents. The paper first analyses the impact of lightning strike point on lightning overvoltage of 1000 kV UHV transformer substation and determines the research object of lightning intruding wave overvoltage. Second, the influence of the impact grounding resistance of transformer side lightning arrester and transmission line tower on invaded wave is analysed. Finally, the commutation failure of HVDC system was analysed, and the simulation tests were carried out by CIGER standard model in PSCAD and Simulink, valve voltage and valve current waveform can be used as a new basis for judgment. The conclusion shows that the analysis of UHV AC/DC hybrid system commutation failure should start from the DC system to study, and commutation failure directly related to the failure, operating conditions, and other factors.

Keywords

• poles and towers
• overvoltage
• overvoltage protection
• power transmission lines
• lightning protection
• arresters
• HVDC power transmission
• transformer substations
• lightning overvoltage
• high UHV AC/DC transmission line tower
• working voltage amplitude
• lightning accidents
• paper first analyses
• lightning strike point
• 1000 kV UHV transformer substation
• wave overvoltage
• impact grounding resistance
• transformer side lightning arrester
• invaded wave
• HVDC system
• valve voltage
• valve current waveform
• UHV AC/DC hybrid system commutation failure
• DC system
• voltage 1000.0 kV