Electrical breakdown of polypropylene film

DC electrical breakdown of polypropylene film was investigated experimentally and discussed theoretically. The temperature dependence of electric strengths and other results suggest the electronic breakdown process in the low-temperature region and the thermal and/or electronic process in the high-temperature region. A new breakdown model is proposed by introducing an electronic breakdown criterion into the thermal breakdown caused by the transient current. Computer simulation was made on the transport of both bulk-generated and electrode-injected carriers during the transient state and the local field distortion. This model could successfully explain the breakdown characteristics not only in the low-but also in the high-temperature region.