Simulation study on the technology of interphase interference and spatial interference in metal oxide arrester (MOA) on-line test

Due to the intensive arrangement of the transformer substation equipment, there is coupling capacitance between conductors, which leads to serious interphase interference and spatial interference in MOA on-line testing. This interference was able to make the leakage current of three-phase arrester in great difference, especially the resistive current, and subsequently, the deterioration situation of arrester valve plate cannot be accurately estimated. In this paper, a simulation model was established based on the interphase interference and spatial interference situation in MOA on-line testing, which aims to analyze the interference mechanism and then to eliminate the interference. Ultimately, the leakage current and phase after filtering out interference can be got by means of interference current calculation with coupling capacitance.