Improvement of harmonic conditions in the AC/DC microgrids with the presence of filter compensation modules

Abstract

The main purpose of this research is to design a new connection of AC/DC microgrids to the grid under power compensation methods to reduce harmonics amplitude by some of the filter compensation devices. The green plug filter compensator (GPFC) is used in the DC side to stabilize the dynamic voltage and reduce the transient voltage. Also, the active power filter module (APFM) is used to reduce the amplitude of current and voltage harmonics in the AC microgrid. Challenges and innovations in this research include optimization of gains coefficients of APFM by some of the heuristic algorithms and applying this setting to the three loops of voltage and current harmonics, as well as controller error to obtain an optimal response to eliminate the current and voltage harmonic range. The optimized coefficients are related to PI controller and the cost function including the controller error, current harmonics, and voltage harmonics. The optimizing coefficients using artificial bee colony (ABC), particle swarm optimization (PSO), harmony search (HS) and differential evolution (DE) algorithms is done to determine the best answer to this problem. Finally, the simulation results show that the use of APFM is essentially effective in reducing system harmonics (more than thirty-percent for current harmonics in the A1 area, and nearly sixty-percent for voltage harmonics) and this effect is more evident by optimizing the APFM control coefficients.