Analysis of Time Domain Characteristic of Transformer On-load Tap-changer

On-load tap-changer is a switching device that provides a constant voltage for a transformer when the load changes. The basic principle is to realize the switching between taps in the transformer winding without interrupting the load current, thereby changing the number of winding turns, that is, the voltage ratio of the transformer, and finally achieving the purpose of voltage regulation. In this paper, the characteristic parameters are collected by time domain analysis method, which provides the basis for discriminating the later fault warning.