Design Of PI and PR controller in Various Reference Frames for Inverter Control

This paper presents a meticulous comparative analysis of Proportional-Integral (PI) and Proportional-Resonant (PR) controllers, specifically examining their performance in αß and dq reference frames for inverter applications. Highlighting the equivalence of PR controllers in stationary frames to PI controllers in synchronous frames, the study underscores PR controllers' superiority in resonant frequency scenarios. Benefits include improved transient response, lower Total Harmonic Distortion (THD), and minimal or zero steady-state error. Notably, the PR controller's ability to impart infinite gain at the fundamental frequency eliminates the need for direct current injection into the utility grid. Simulation-based evaluations elucidate the controllers' steady-state (SS) responses, offering valuable insights into practical applications.