Research on Harmonic Detection Method of Multi-function Grid-connected Inverter

Aiming at the functions of active filtering and reactive compensation of multi-function grid-connected inverter, this paper analyzes the advantages and disadvantages and applicable conditions of existing harmonic detection methods. Under different grid voltage conditions, the simulation and analysis of PQ detection method and ip-iq detection and harmonic detection method under FBD power theory are carried out. After comparative analysis, under normal power grid voltage conditions, FBD power theory harmonic detection method is fast and accurate, and under power grid voltage distortion conditions, 1̅_p - 1̅_q harmonic detection method has high precision.