High-voltage frequency domain dielectric spectrum characteristics of oil-paper insulation bushing at different temperatures

As a key equipment of the power transformer outlet device, the safe and reliable operation of high-voltage bushing is particularly important. Oil-paper insulation type bushing is the most important bushing form in electrical engineering. Testing the dielectric loss factor and capacitance to judge the bushing status is easily affected by temperature and is not sensitive enough; while the conventional frequency domain dielectric spectroscopy test voltage is limited and the anti-interference ability is poor. In order to accurately detect the defects of transformer oil-paper insulation bushing, this paper builds a high-voltage frequency domain dielectric spectrum test platform based on the frequency domain dielectric spectrum theory. By controlling the moisture degree and aging state of the oil-paper insulation bushing samples, the high-voltage frequency domain dielectric spectrum characteristics at different temperatures are analyzed, which provides a theoretical basis for on-site evaluation of bushing defects and improvement of bushing operation reliability.