High voltage circuit breakers are important protection and control equipment for the power grid. The defects and faults of the circuit breaker seriously affect the safety and stability of the power system. As the key component of the operating mechanism of the circuit breaker

the opening/closing coils contain a large amount of information about the operating status of the mechanism. In order to investigate the cause of the difference in the current waveforms

this paper analyzes the factors affecting the circuit breaker opening/closing coil current through the simulation of the defect and fault in the actual circuit breaker

and distinguishes the fingerprint characteristics difference of the opening/closing current caused by the environmental difference and structural difference. At the same time

the characteristics of coil current changes under four different types of mechanism defects are analyzed. The key points of status evaluation of circuit breaker mechanism base on opening/closing current waveform are proposed

which lays a foundation for the practical application of intelligent status evaluation of circuit breaker.