New method for evaluating high-field dielectric properties of polymeric insulating materials

A method for the detection of the AC electric field dependence of tan delta immediately after electric field application is developed. This property is evaluated using the response to rapidly rising ramped sinusoidal applied voltage. The time variation of tan delta can also be evaluated within a few seconds of applying the voltage. This technique is used to measure high-field dielectric properties and their relation to the AC dissipation current waveforms of an LDPE (low-density polyethylene) film.<
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