Research On Key Technologies Of Calibrating Insulating Oil Dielectric Strength Tester

In power electrical system, insulating oil is a kind of insulating material which iswidely used in electrical equipment. Breakdown voltage is an important index thatevaluates the quality of insulating oil dielectric strength which will change afterlong-term operating. The quality degradation of oil will lead to the insulationcharacteristics of electrical equipment decline. In order to ensure the equipmentrunning safely, the insulating oil dielectric strength should be tested regularly. Soinsulating oil dielectric strength tester is widely used in power electrical system.At present there are many kinds of insulating oil dielectric strength testers indomestic market. But the standard of calibration is still up in the air. It is difficult tocalibrate this equipment with enough accuracy as a result of the particularity ofelectrode structure and the approximately calibration method. It is necessary todesign a standard device for calibrating insulating oil dielectric strength tester in orderto solve this technical problem. The target of this paper is to develop a standard devicefor insulating oil dielectric strength tester calibration which has the function of vectormeasurement. It is applied to calibrate insulating oil dielectric strength tester with0-100kV output voltage and with2%accuracy for the best.The main part of this paper introduces the structure and operational principle ofthe calibration device, designs the measuring device of capacitor voltage divider andevaluation of measurement uncertainty. The standard device can fulfill the functionsas following:(1)0-100kV measuring voltage range (2) measurement uncertainty bestthan0.5%(3) vector measurement (4) the impedance match of oil cup.