Research On Full Band Synthetic Partial Discharge Detection In Transformer

The research of partial discharge detection in transformer is one of the key items of transformer on-line monitoring and fault diagnosis.A large number of theories and practices have proved that the single-type partial discharge detection technology has obvious limitations and can not meet the requirements of the field.The joint detection technology based on multiple partial discharge sensors is the focus and trend of future research.From the perspective of solving practical problems.This article used the combination of high frequency current,ultrasonic and ultra-high frequency(UHF)methods,it is of great theoretical and practical significance to study the integrated detection and analysis method of partial discharge in transformer and to develop an integrated detection device fusing multiple detection techniques.Firstly,the propagation modes and characteristics of partial discharge signal in transformer were studied.According to the characteristics of different partial discharge signals,the propagation principle and characteristics of high frequency current,ultrasonic signal and UHF in transformer are studied respectively through modeling simulation,which lay a theoretical foundation for the research of the subject.Secondly,partial discharge signal conditioning unit and power supply unit were designed.Partial discharge of high frequency current,ultrasonic,UHF sensor operating band is different,also the characteristics of the test signal is different.So we need to develop or select the appropriate sensor according to the partial discharge characteristics.In addition,considering the three kinds of sensor detection signals corresponding to the simulation conditioning unit are different,so the conditioning unit for each sensor need to design their own amplification,such as amplifier filtering shaping circuits and so on.Finally,based on the oscilloscope's high-speed acquisition function,a full-band integrated partial discharge detection device using a variety of detection techniques was developed,which can support the detection of three kinds of partial discharge signals.The operating system and programming interface provided by the oscilloscope are used to develop a partial discharge synthesis Analysis of diagnostic software,the system can also realize three kinds of partial discharge signal detection and complete full band comprehensive diagnostic to meet the partial discharge field detection of the actual application needs.