Analysis And Application Of Breaker Failure Protection Fault Characteristics In Dongguan Power Grid

With the continuous development of society and economy,people’s living standards are increasing day by day,and the requirement for security and stability of power supply is getting higher and higher.Relay protection is an important protective barrier for the safe and stable operation of power system.It can remove system faults quickly,sensitively and reliably,but it can not avoid the rejection of circuit breakers.At this time,the near-backup protection of circuit breaker failure protection plays an important role.Through the reliable action of circuit breaker failure protection,other circuit breakers on the bus will be jumped off,so as to carry out the accident.Barrier isolation to prevent the expansion of power grid accidents.However,the application of circuit breaker failure protection in power grid is not mature,and malfunction protection often occurs due to various accidents,which brings huge losses to power grid.Therefore,a detailed analysis of the failure of circuit breakers and corresponding countermeasures are important to improve the correct rate of the failure protection action of circuit breakers.Firstly,this paper briefly introduces the principle and setting principle of circuit breaker failure protection.On the basis of the application of circuit breaker failure protection in Dongguan Power Supply Bureau,it introduces the basic structure and realization mode of three basic components: starting circuit,protection logic and outlet circuit of failure protection.Then,the application status of failure protection device in Dongguan power grid is analyzed.Starting from the three basic components of circuit breaker failure protection starting circuit,protection logic and outlet circuit,this paper selected several typical accident cases which caused circuit breaker failure protection malfunction in Dongguan power grid.It mainly includes: incomplete start-up circuit,defective protection logic,incomplete outlet circuit and so on.It summarizes the risk factors of circuit breaker malfunction protection malfunction,and puts forward improvement measures for the problems existing in the application of circuit breaker malfunction in Dongguan power grid.Finally,the proposed scheme is applied to the optimization of 220 kV Yuyuan station circuit breaker failure protection,and the feasibility of the optimization improvement scheme is verified from the hexagonal diagram to verify the correctness of current circuit and the correctness of failure protection belt load transmission.The results show that the proposed optimization and improvement scheme can ensure the safe and stable operation of circuit breaker failure protection and improve the correct operation rate of failure protection.The research results of this paper have certain guiding value.