Research On Condition Monitoring System For High Voltage Circuit Breaker

With the UHV and smart grid proposed in China,it becomes increasingly important to ensure the safe operation and stable operation of power systems and electrical equipment.In this context,experts and scholars pay more attention to condition monitoring and fault diagnosis of electrical equipment.As important primary equipment in power system,high voltage circuit breakers have control and protection functions.And it plays a vital role in the safe operation and stable operation of power systems.Therefore,the fault of high voltage circuit breaker can be detected by condition monitoring and fault diagnosis technology.It can improve the reliability and safety of high-voltage circuit breakers in operation.In addition,predictive maintenance can be achieved by monitoring the operation condition of high-voltage circuit breakers.And it can avoid unnecessary maintenance and power blackouts,which increases equipment maintenance cycles and improve equipment utilization,reduce maintenance costs,which have important economic and social benefits.The paper introduces the basic types of high voltage circuit breakers.Take SF₆ high voltage circuit breaker widely used as an example to analyze its basic structure.Then,it introduces the common faults of high voltage circuit breaker.The basic requirements for high voltage circuit breakers condition monitoring is presented by various fault types.The selected method for mechanical characteristic parameters of high voltage breaker is listed.And each signal characteristic extraction method is presented.Based on the adsorption potential,quantitative description of adsorption effect is taken.The effect of adsorption effect on humidity monitoring is studied.The system structure of high voltage circuit breaker condition monitoring is introduced,also with the function modules and functions.On this basis,solutions to on-line state monitoring for SF₆ gas and mechanical characteristic in high voltage circuit breaker is proposed respectively from the point of condition monitoring principle,hardware structure and software process.Finally,it is applied to the SF₆ high voltage breaker of 500 kV Xin'an substations.The paper contrasts the coil current waveforms measured by the condition monitoring system of circuit breaker with that measured by test table in Xi'an XD Switchgear Electric Co.,Ltd.The result validates that the condition monitoring system of high voltage circuit breaker developed in the paper is effective and feasible.