Inverter harmonic suppression based on adaptive resonant controller

With the increment of non-linear loads such as chargers, harmonics caused by those loads make much damage to the grid and other electrical equipment. The rectifier load as one of typical nonlinear load is taken as the research object in this paper. The output waveform optimization in harmonic suppression is the target. Firstly the double closed-loop control scheme is used to control the inverter and harmonics caused by the rectifier loads is analyzed. Then instantaneous reactive power theory is adopted to detect the harmonics. Finally adaptive proportional resonant controller is used to complete harmonic suppression and parameter adaptive adjustment. A simulation model of inverter system is established to analyze the harmonic content of the system under different control schemes. The output voltage harmonic content is reduced from 6.52% to 2.26% in the actual system, effectively improves the inverter output waveform quality. The result verifies the validity of proposed adaptive resonant controller.