A Novel Phase Locked Loop based Control Strategy for a Three-phase Grid-tied Solar PV System

Abstract

This paper presents a novel control strategy for a three-phase grid-tied solar photovoltaic (PV) system and the proposed control strategy employs sliding discrete Fourier transform (SDFT) based Phase Locked Loop (PLL) for the extraction of the fundamental grid frequency component to generate accurate reference grid currents. The accurate and precise detection of phase angle and grid frequency defines the effectiveness of the proposed controller. The outer DC voltage control loop can effectively reduce the peak overshoot in DC-link voltage during transients. Multifunctional operation of the grid-connected VSI improves several power quality (PQ) issues and retains the power injection to ensure the consumer requirement. Finally, the performance of the proposed controller is validated by MATLAB®/Simulink and followed by dSPACE-1104 based hardware-in-loop (HIL) simulation results.