Analysis on insulation aging failure of pulse capacitor

The pulse capacitor, as the important energy storage device, its stability will directly influence the dependability of the pulse power system that capacitor located in. Life-span of the capacitor has strong relationship with its working dependability, In this paper, by charging and discharging to the pulse capacitor and testing direct current partial discharge to the capacitors at different stage of life-span, the three curves of relation between life-span and maximal discharge magnitude, mean discharge magnitude, mean discharge frequency were obtained. Observing the surface topography of capacitor film at different stage of life-span by the scanning electron microscopy, analyzing the influence of charge and discharge aging test to its surface topography. Finally referring to the actual situation of capacitor breakdown and summarizing the factors that caused the variation of pulse capacitor partial discharge performance, pointing out that some insulating defect existed in the edge area of electrodes was the main reason that caused the capacitor breakdown.