Bushing maintenance is a normal operation in power substations, but the maintenance cycle is too long in fixed period power outage maintenance schemas which decreasing the maintenance accuracy. In this paper, an on-line brushing monitoring system is proposed to change the situation. A kind of on-line monitoring device for the end shield of the bushing is developed to ensure casing equipment insulation defects in time. According to the structure of the system, the design of the local signal conditioning circuit, the high-speed acquisition circuit and the power function circuit are demonstrated. Finally, the test results show that the on-line monitoring system is effective for monitoring the test results show that the on-line monitoring system is effective for monitoring the running state of high voltage busing in real time.

high voltage bushing,high speed acquisition circuit,insulation defect,on-line monitoring,the vibration test