Analysis of ping-pong type of rotor earth fault protection

In view of the problem of current ping-pong-type of rotor earth fault protection,t his paper does theoretical analysis and simulation on its measuring accuracy from the the aspects of excitation voltage change,the components parameters selecting and AC components,etc.The experimental results show that the accuracy is different when the bridge arm resistance and measurement resistance are different,protection also changes accordingly in accuracy with excitation voltage changed.In order to minimize the impact of the AC component,Fourier algorithm is used to filter the measurements.The simulation results confirm the correctness of theoretical analysis.Measurement data and measurement accuracy can meet the actual demand.