Harmonic Suppression of Grid-Forming Inverters Based on QPMR Controller

Based on the presence of numerous nonlinear loads and the resulting harmonics in grid-forming scenarios, a harmonic suppression method for grid-connected inverters was studied. For the double-loop inverter control using QPR, the voltage feedforward was removed to make it suitable for harmonic suppression. The harmonic generation mechanism was analyzed, and the relationship between harmonic impedance and harmonics was derived, shifting the objective towards suppressing harmonic impedance. A comparison between QPMR and QPR was made, demonstrating that QPMR is more effective for harmonic suppression. A simulation model was built to verify the feasibility of harmonic suppression using QPMR.