Development dynamics research of signals from partial discharges in capacitor paper

As a dielectric of sections in power capacitors the impregnated-paper, sheet-impregnated-paper or film insulation imbued with a liquid dielectric is applied. The electric strength of a liquid dielectric is much lower than strength of an imbued paper or film. Therefore partial discharges (PD), most responsible for process of ageing of electrical insulation arise, first of all, in a liquid dielectric. The intensity of electromagnetic radiation near to a dielectric under high voltage was investigated experimentally. It was shown, that the amplitudes of signals relate legibly to field strength in a dielectric and to development of PD. In paper-oil insulation such as KON-1 the signals of electromagnetic radiation from PD can be observed from field strength of the initial PD. The degree of increase of intensity of electromagnetic signals from PD depends on value of field strength in a dielectric. When field strength changes from initial up to a critical level the rate of signals increase from PD amounts to 0.69 dB/(kV/mm), with field strength change from critical up to breakdown value of 1.7 dB/(kV/mm).