Local Fault Mechanism of Multi-Column In-Parallel Surge Arresters in UHV DC Converter Station
In order to meet the energy absorption requirements,the surge arresters in UHV DC converter stations usually adopt the structure of multi column parallel connection.However,due to the non-uni-form current and absorbed energy,multi column parallel surge arresters are prone to local faults,leading to system lockout.In order to clarify the fault mechanism,the author analyzes the operating conditions and structural characteristics of the metal return transfer switch (MRTB)arrester and the neutral bus EM arrester that are prone to local faults in the DC converter station,studies the occurrence process,fault phenomena and troubleshooting results of the unbalanced fault,and summarizes the causes and mecha-nisms of local faults from the microstructure of zinc oxide varistor to the parallel characteristics of the ar-rester group.The corresponding countermeasures are proposed.
万方数据
维普
