@ARTICLE{Gałecki_A._Grid-tied_2020, author={Gałecki, A. and Michalczuk, M. and Kaszewski, A. and Ufnalski, B. and Grzesiak, L.M.}, volume={68}, number={No. 2 (i.a. Special Section on Computational Intelligence in Communications)}, journal={Bulletin of the Polish Academy of Sciences Technical Sciences}, pages={389-398}, howpublished={online}, year={2020}, abstract={The paper presents a three-phase grid-tied converter operated under unbalanced and distorted grid voltage conditions, using a multi-oscillatory current controller to provide high quality phase currents. The aim of this study is to introduce a systematic design of the current control loop. A distinctive feature of the proposed method is that the designer needs to define the required response and the disturbance characteristic, rather than usually unintuitive coefficients of controllers. Most common approach to tuning a state-feedback controller use linear-quadratic regulator (LQR) technique or pole-placement method. The tuning process for those methods usually comes down to guessing several parameters. For more complex systems including multi-oscillatory terms, control system tuning is unintuitive and cannot be effectively done by trial and error method. This paper proposes particle swarm optimization to find the optimal weights in a cost function for the LQR procedure. Complete settings for optimization procedure and numerical model are presented. Our goal here is to demonstrate an original design workflow. The proposed method has been verified in experimental study at a 10 kW laboratory setup.}, type={Article}, title={Grid-tied converter operated under unbalanced and distorted grid voltage conditions}, URL={http://journals.pan.pl/Content/116287/PDF/25D_389-398_01438_Bpast.No.68-2_25.04.20_K1G.pdf}, doi={10.24425/bpasts.2020.133109}, keywords={grid-tied converter, AC/DC converter, current controller, resonant controller, particle swarm optimization}, }