Reduced Design of PR Controller in Selected Harmonic Elimination APF Based on Magnetic Flux Compensation

Proportional resonance (PR) controller can achieve zero steady-state error control of sinusoidal signal by providing infinite gain at resonance frequency and quasi PR controller enhances the tolerance to grid frequency offset by increasing the controller bandwidth. However, each controller in stationary reference frame (SRF) responds to only one harmonic, so many controllers are necessary when multiple harmonics are compensated at the same time, which will consume a large number of hardware resources and reduce system stability. A reduced design of PR controller for multiple harmonics compensation is presented in this paper. A h
^th
PR controller implemented in a frame rotating at rω
₀
can compensate both (h+r)
^th
and (h-r)
^th
harmonics, which is, each PR controller is characteristic of dual harmonics compensation. The model of a three-phase selected harmonics elimination (SHE) APF was built on MATLAB/Simulink and related simulation results verified the effectiveness of the proposed reduced PR controller design methods on multiple harmonics compensation.