Analysis on a False Action Accident of 110kV Line Protection Reclosing and Its Improved Measures

Reclosing is an important technology in relay protection and generally is allowed to act only once. Then the cause of false action of reclosing should be found out as much as quickly, and improved measures should be carried out. An accident on multiple false actions of reclosing after the 110kV Gu\|Kuai line permanent fault occurred in 220kV Gu\|Shan substation and loss of substation electricity is analyzed deeply in this paper, then some security risks exist in reclosing loop circuit, stored energy source of breaker and operating standards are pointed out, and some improved measures are proposed, which can avoid similar accidents to improve security of relay protections and provide some references.