Research And Application Of On-line Monitoring Partial Discharge System For Power Transformer

An important factor in power transformer partial discharge will lead tooil-paper insulation aging and deteriorating even cause breakdown, affecting safeand stable operation of the transformer， The transformer’s inner insulationoperating condition assessments can be performed by the online partialdischarge(PD) monitoring, Early prevention of accidents and problems of growinghas important practical significance， so the PD monitoring becomes a statemaintenance research focus of electrical equipment in recent years. This papersummarizes the inheritance and advanced research experience abroad，Cooperatingwith the UHF sensor, HFCT sensor and AE sensor as the core equipments and usingthe graphical programming language LabVIEW7.1, to develop an on-linemonitoring PD system, the electro-acoustic joint monitoring system for transformer PDsingle has been built. Isolated system can not overcome the traditional internal transformerpartial discharge can not be more comprehensive monitoring of the drawbacks,The systemwith strong anti-interference can improve the measurement sensitivity，positioning accuracyand data processing rate. In addition the system through the internal structure andoptimization of transformer design integration inline installation, reduced electromagneticinterference system balancing transformer itself, improve the sensitivity and anti-jammingcapability.Through the on-line operation of3transformers in one110/10Kv undergroundsubstation, the results show that the system can real time detect the transformer’s PD signal,And the system functions have reached the design requirements，which can provide muchcreditable data for transformer state maintenance.