Research on the inversion calculation method of overvoltage based on the nonlinear model of potential transformer

Monitoring overvoltage is essential to the power system's operating well. Potential transformer is an important measuring instrument in power station. Because of the high amplitude of lightning overvoltage and switching overvoltage, the iron core of potential transformer reaches saturation in a very short time. The iron core shows nonlinear characteristic, so the distortion of secondary voltage and current happens. This article uses a nonlinear model of 10kV potential transformer to restore the primary voltage from the secondary voltage by the inversion calculation.