Wide bandwidth single and three-phase PLL structures for grid-tied PV systems

Abstract

This paper presents a detailed description of a three-phase PLL (phase-locked loop) structure that fits the requirements of utility connected PV systems. The tuning of the PLL structure is discussed as well as its under utility distorted conditions. A new single-phase PLL topology is introduced. Its dynamic behavior is evaluated and its quasi-instantaneous ability to detect phase, frequency and amplitude of the utility voltage is highlighted. The analysis of the performance of the introduced single-phase PLL topology under islanding condition is also presented. Simulation and experimental results are included to support the theoretical study.