Research of On-Line Detection for Power Capacitor

This paper presents an idea that partial discharge event always in initial phase of power capacitor's on-line failure. Based on this idea, a device introduced for on-line detects partial discharge to prevent latter failure. Simulation using wavelet-transform in MATLAB 6.5 for pick up partial discharge signals from collective data was conducted. Another simulation also using wavelet-transform for de-noises collective data in on-line measurement of capacitor's tgdelta was conducted too. Simulations indicated that wavelet can pick up PD signals, and wavelet can reduce error and get further accuracy in tgdelta's on site measurement