Parameter Identification of Resonant Earthing system Based on Signal Inputting Approach and Fast Fourier Transform

The paper proposes an integrated surveying approach for earth capacitor and arc suppression coil (ASC) inductor in resonant earthing systems based on the signal inputting approach and Fast Fourier Transform (FFT). First of all, the relationship between the normal voltage and the system value is definite. Then, a non-power frequency current source is connected to the normal point, and the frequency formation of the normal point current source is obtained using FFT to remove the power frequency fault. As a result, the equivalent circuit allows for the combined surveying of earth capacitor, inductor of the ASC, achieving a unified metrology approach. In a word, a simulation model is built using Simulink, demonstrating the suitability of this approach for a lot of types of ASCs. Under three-phase asymmetry conditions, the maximum faults of earth capacitor and ASC inductor are 0.1% and 0.11% separately.