Power system nonlinear load power metering method based on improved S transformation

The invention discloses a power system nonlinear load power metering method based on improved S transformation, and the method comprises the following steps: 1, carrying out the extraction of a voltage fundamental component, a current fundamental component and a distortion component based on IST, and obtaining a voltage fundamental part signal, a current fundamental part signal and a distortion part signal respectively; 2, through IST inverse transformation, fundamental wave discrete signals and distortion discrete signals of the voltage and current signals are reconstructed; and step 3, dot product sum operation is carried out on the fundamental wave discrete signals and the distortion discrete signals of the reconstructed voltage and current signals, and power metering of the signals can be completed. When the IST-based decomposition and reconstruction algorithm provided by the invention is used for metering the power under the condition that harmonic waves and nonlinear loads exist, the metering precision