Research on Time-domain Dielectric Response of Multiple Impulse Voltage Aging Oil-film Dielectric

Power capacitors suffer multiple impulse voltage during their lifetime. With the multiple impulse voltage aging, the insulation - oil-film dielectric, may deteriorate and even fail in the early stage. The time-domain dielectric response of oil-film dielectric with multiple impulse voltage aging is studied in this paper. At first, an aging and testing platform for oil film medium under impulse voltage was built to test the time-domain dielectric response (polarization depolarization current, PDC) of oil-film dielectric with multiple impulse voltage aging. And then, according to tested PDC, extended Debye model and characteristic parameters were obtained by matrix pencil algorithm identification. The results show that with the increase of impulse voltage times, the time-domain dielectric response of oil-film dielectric changes accordingly, as well as the branch parameters and characteristic parameters of the extended Debye model. At last, the test results are discussed.