An improved adaptive harmonic detection method applied in shunt APF

This paper introduces a new strategy to improve the applicability of adaptive filters for harmonic detection in shunt active power filters (SAPF). Aiming at the traditional fixed-step adaptive harmonic detection has self-contradiction among the convergence rate, time-varying system, tracking speed and convergence precision, an improved adaptive harmonic detection based on a new LSM algorithm with variable step which is researched in this paper. The new algorithm has a fast response while ensuring high precision. The theoretical analysis is proposed and simulations using Matlab/Simulink tools are presented to clarify the algorithm.