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 phaseangle 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.

Parallel filtering scheme for fast symmetrical component extraction based on asynchronous coordinate transformation

“…Another approach to extract a desired symmetrical component is to utilize secondorder filters which can target a specific frequency component of the signal including adaptive notch filtering methods (Yazdani, 2008;Yazdani, 2009;Gonzalez-Espin, 2012;Yin, 2013;Lee, 2014) and second-order generalized integrator (SOGI) methods (Hackl, 2020;Golestan, 2017;Xin, 2016;Reyes, 2012;Rodriguez, 2007). Recently, Hoepfner (2023) presented an SOGI method to reduce the computational burden but without decreasing the time delay. Bamigbade (2022) presented a kind of notch filter with the frequency-adaptive capability based on cascaded integral action, which, however, does not reduce the time delay either.…”