Simulation and Analysis of Fundamental Current Extraction Algorithm based on Simulink

With large number of nonlinear loads connected to the grid, harmonic pollution has become an increasingly serious problem. This paper analyzes the theory of p-q method and ip-iq method based on instantaneous reactive power theory. Results of analysis reflect the difference of the two methods on accuracy of fundamental currents extraction with or without voltage distortion. Simulation models of p-q method and ip-iq method are established respectively on Simulink. Research results show that ip-iq method can accurately detect fundamental currents in both two cases. However, p-q method has significant error when there is voltage distortion. The experimental results validate the theoretical analysis.