交流中压真空断路器机械特性在线监测装置的研制

Among all the faults of the circuit breaker, the mechanical fault occupies a considerable proportion. It is of great significance to take the on-line monitoring method for mechanical characteristics. This paper is devoted to the investigation of 12 kV AC medium voltage vacuum circuit breaker, develops an on-line monitoring device for it. This device is based on STM32F407 and is equipped with RT-Thread real-time operating system, monitoring the current signal of the opening and closing coils, the angular displacement signal and the vibration signal. HNC-661 Hall current sensor was used to collect the current signal of the opening and closing coils for judging the starting time of the opening and closing operation of circuit breaker. WDD35D4-5kΩ angular displacement sensor is used to measure the travel-time curve of the movable contacts indirectly, contributing to the avoidance of high voltage isolation problems of linear displacement sensors. The vibration signal of the operation process of the circuit breaker is collected by the ADXL001-70BEZ vibration sensor. After the vibration signal is processed by the short-time energy method, the opening and closing instants can be determined, and the mechanical parameter calculation is performed on this basis. This device has the functions of liquid crystal display and data uploading, and realizes online monitoring of the circuit breaker. Compared with the mechanical property tester, the monitoring data of the mechanical characteristic of this device is stable and reliable.