抄録
Extended chain crystal (ECC) polyethylene subjected to a high voltage exhibits some unique properties. Electrical trees were investigated using a needle to plate electrode system under a lightning impulse voltage, application. The propagation direction of the trees was strongly influenced by the orientation of the ECC polyethylene. When the needle electrode was normal to the orientation, some linear trees with no branches always propagated along the orientation. When the needle electrode was parallel to the orientaion, the tree propagated as a single line without branching along the orientation. The current following tree formation was observed as intermittent sharp pulses in the wave tail of the applied voltage. The number of pulses was dependent on the peak value of the impulse voltage and on the sample's temperature. The tree inception voltage was also dependent on the sample's temperature. These experimental results are represented in the form of an Arrhenius plot for discussion the tree inception process in test samples.
