Research And Design On Online Monitoring System For 10kV Intelligent High Voltage Vacuum Circuit Breaker

High-voltage circuit breaker is an important control and protection equipment in the power system.Maintenance and repair for high voltage circuit breakers to ensure its normal operation is the key of reliable operation of power grid.Online monitoring and fault diagnosis of high-voltage circuit breakers can detect faults in time,and provide conditions for condition based maintenance,meanwhile improve power supply reliability,equipment utilization,and reduce maintenance costs.There are some problems that required further study and discussion of online monitoring system of high-voltage circuit breaker: the monitoring parameters are insufficient,the accuracy of fault diagnosis is affected by the accuracy of sampling precision,signal fault feature points and intelligent diagnosis algorithm,and the ability of anti-interference is inadequate.The paper bases on the problems of monitoring parameters are insufficient and the accuracy of fault diagnosis is affected,presents a design program of online monitoring system of high voltage circuit breaker.The program adopt TMS320C28346 as the system control core,16-bit AD7606 as sampling chip,monitoring parameters includ coil current,energy storage motor current,contact trip,contact temperature.The system can accomplish acquisition,data processing,LCD12864 liquid crystal display,U disk data storage and fault diagnosis,and integrated RS485 communication interface to achieve long-distance data transmission.The fault diagnosis is based on EMD and eigenvalue judgment,coil current and contact travel are decomposed by EMD algorithm to obtain the key points of the fault feature,energy storage motor current is denoised by EMD algorithm to obtain the fault feature,such as energy storage time,finally judge fault according to whether the characteristic value is within the normal threshold.By setting up the experimental platform in the laboratory,taking the ABB vacuum circuit breaker VD4 as the monitoring object,the measurement result of GYT₀7 of Xiamen Guoyi Technology Co.,Ltd as the standard contrast data,paper verifies the accuracy of the online monitoring system of high voltage circuit breaker.Experimental results show that the system of the high voltage circuit breaker on-line monitoring can achieve real-time monitoring of coilcurrent,energy storage motor current,contact trip,contact temperature,can detect faults in time,has the advantages of high measurement accuracy and good real-time performance.