Key Technologies For Ultra-Wideband Pds Detection In Transformer Under Ac/Dc Withstand Voltage Tests, Part 1: Application Status Of Conventional Pulse Current Method

As the core equipment of the power grid, the operating state of the transformer will directly affect the stable operation of the power grid. Partial discharge (PD) is the main reason for the insulation failure of large transformers, and it is currently the primary means of assessing the degree of insulation degradation. Partial discharge detection is an important indicator for measuring the reliability of the internal insulation structure of electrical equipment. The purpose of PD test is to verify whether there is a discharge source inside the transformer. As the earliest proposed and most developed method, the pulse current method is widely used in actual detection. This paper reviews the detection principle and application scope of the method, as well as the derived ultrasonic or ultra-high frequency (UHF) joint detection methods. Meanwhile, this paper analyzes the principles, advantages and disadvantages of every detection method. Finally, given the research and application situation of pulse current method detection, this paper looks forward to its future development.