Study on Impact Response Characteristics of Capacitive Voltage Transformer

Abstract

Under the impact voltage, the internal capacitive components of the capacitive voltage transformer are subjected to different voltages. Understanding the impulse response characteristics of the capacitive voltage transformer is of great significance for analyzing the internal insulation fault of the capacitive voltage transformer. In this paper, from the disintegration of a 500kV capacitive voltage transformer, based on the actual measurement of the capacitor and its internal components, the distributed parameter model of the capacitive voltage transformer is established. The response of the capacitive voltage transformer to the surge voltage is analyzed under the condition of lightning intruding wave and long line closing. The analysis shows that the capacitive element of the high-voltage side capacitor divider of the capacitive voltage transformer is subjected to the first and last ends of the capacitive voltage transformer. The voltage is higher than other capacitive components; when a partial capacitive component breaks down in the capacitive voltage divider, the voltage drop of the normal component under the same surge voltage increases, which will accelerate the damage of the capacitive component caused by the surge voltage; analysis conclusion and disintegration The results are in agreement and are of great significance for analyzing the internal insulation damage of capacitive voltage transformers.