Study of effect of pre-applied voltage on conduction in polyethylene

The dependence of polyethylene conductivity on preapplied voltage and the way to eliminate the preapplied voltage effect are investigated. Instantaneous conductivity increases with preapplied voltage and the time under the voltage, and is related to the polarity of the voltage. Space charge in polyethylene can be eliminated by an alternating high voltage. However, using a power frequency source is more convenient. Samples of polyethylene should be pretreated with power frequency voltage or high frequency voltage before conductivity measurement, which should be written into test standards for the conductivity of dielectrics.<>