A Novel PR Controller with Improved Performance for Single-Phase UPS Inverter

Modern uninterrupted power supplies (UPS) are gaining popularity as they can deliver clean and high-quality power under extreme load condition for sensitive devices (like medical, military and communication equipment). Traditional proportional-integral (PI) based control for UPS system provides high-quality output but suffers from the poor dynamic response. In this paper, a novel proportional resonant (PR) controller is proposed for controlling the output voltage of a single-phase inverter. The proposed controller provides a fast-dynamic response, low or zero steady-state error, and reduced total harmonic distortion (THD). A detailed step by step procedure to design the novel controller is presented based on the specific criteria (like steady-state error, overshoot, etc.). Due to the fast response, the proposed PR controller is also suitable for EV charging applications (specifically to the vehicle to load charging). Simulation and experimental results are presented to validate the feasibility and efficacy of the proposed controller.