A Three-Phase Frequency-Fixed DSOGI-PLL With Low Computational Effort

Abstract

This paper offers a detailed analysis as well as a tuning and discretization approach of the presented frequency-fixed dual second order generalized integrator based phase-locked loop (FFDSOGI-PLL) for three-phase power systems. The method combines different single- and three-phase PLL approaches by ensuring high phase- and frequency tracking properties. The comparison with the standard frequency-variable DSOGI-PLL and three different recently published three-phase frequency and phase-angle estimation systems shows, that this approach gives a fast and stable phase and frequency detection of the grid voltage with very low computational burden. The results are applicable to, for instance, photovoltaic or frequency converters or active power filters.