Intrinsic AC breakdown of low-density polyethylene film above room temperature

The intrinsic AC electrical breakdown of low-density polyethylene film was studied above room temperature under the partial-discharge-free condition using McKeown-type specimens. The dependence of AC electric strength on the temperature, the rise rate, and the frequency of applied electric field suggests that, under AC voltage application, the thermal process might be dominant rather than the electronic process. The results are also discussed in terms of the dependence of the high-field dielectric dissipation factor on the applied electric field and the voltage application time