交流中压真空断路器机械特性在线监测装置的研制

Development of On-line Monitoring Device for Mechanical Characteristics of AC Medium Voltage Vacuum Circuit Breaker

在断路器所有故障中,机械故障占有相当大的比重,对其机械特性在线监测具有重要现实意义。文中针对某12 kV交流中压真空断路器,以分合闸线圈电流信号、角位移信号及振动信号为监测对象,研制了一种以STM32F407为主控芯片、搭载RT-Thread实时操作系统的交流中压真空断路器机械特性在线监测装置。该装置采用HNC-661霍尔电流传感器捕获分合闸线圈电流,判断断路器分合闸的动作起始时刻;在低电位处采用WDD35D4-5kΩ角位移传感器替代直线位移传感器间接测量动触头的位移曲线,有效避免了直线位移传感器在高电位处的隔离问题;利用ADXL001-70BEZ振动传感器采集断路器动作过程的振动信号,经短时能量法处理后提取出断路器刚分刚合时刻的振动事件,并在此基础上进行机械参数计算。该装置完成机械特性参数计算后可实现液晶显示、数据上传功能,实现了对断路器机械特性的在线监测。经过与机械特性测试仪对比测试,该装置的机械特性监测数据稳定可靠。

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.WDD35D4-5kΩangular 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.