Design Of On-line Partial Discharge Monitoring System For Transformer

Transformers are an important part in the power system,and partial discharge(PD)is an important parameter which can reflect the insulation state of power transformer.Therefore, on-line partial discharge monitoring can find out the state of the transformer insulation, discover incipient fault in time, avoid the transformer insulation breakdown and short-circuit accident caused by PD, which can improve the operation reliability of transformer.First of all, according to the partial discharge characteristics of the transformer and measurement requirements,a on-line partial discharge monitoring system for transformer is designed. Its hardware system is composed of the wide band current sensor, the signal processing circuit and the PD signal collecting unit. The software system is developed based on the LabVIEW software development platform, which can realize the intelligent control for PD data collection.Secondly, based on the analysis of PD signal characteristics, the types and characteristics of noise and interference, a layered and multi-period cumulative approach is proposed on signal processing, and the simulation results proved that the method is reasonable.At the same time, in order to verify the performance of the designed transformer PD monitoring system, the test platform for measuring PD is built in the lab, and the hardware and software of PD monitoring system are tested and debugged, respectively.Experimental results show that the system can meet the design requirements, the effect of signal acquisition and interference elimination is preferable, which can prove that the system has good on-site application prospect.