A new unbalanced voltage compensation method based on Hopf oscillator for three-phase DC/AC inverters with unbalanced loadsA new unbalanced voltage compensation method based on Hopf oscillator for three-phase DC/AC inverters with unbalanced loads Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2023-12-042022enThis work was supported in part by the Program “Bilateral and Multilateral Research and Technology Co-Operation Between Greece and China” under Grant 2017YFGH001164 and Grant eSOLAR/T7ΔKI-00066.In islanded microgrids, distributed generators (DGs) are employed as distributed compensators to improve the power quality on the load side. Due to the access of unbalanced loads, the low-voltage microgrid will naturally exhibit three-phase unbalance, which may cause additional power losses and deteriorate power quality. Therefore, this paper proposes a novel unbalanced-voltage compensation control method based on the Hopf oscillator, which introduces the negative-sequence voltage and current into the traditional Hopf oscillator to achieve the negative sequence voltage droop characteristics. It can not only realize the negative sequence droop control of a single inverter, but it is also capable to support the reactive power automatic distribution between multi-parallel grid-forming inverters. Compared with the traditional unbalanced voltage compensation method based on filtered negative sequence reactive power, the proposed unbalanced voltage compensation method can slightly improve the dynamic response. Experimental results verify the effectiveness of the proposed control strategy.http://creativecommons.org/licenses/by/4.0/IEEE Transactions on Smart Grid1364245-4255 Luo Siyi Wu Weimin Koutroulis Eftychios Κουτρουλης Ευτυχιος Chung Henry Shu-Hung Blaabjerg, Frede, 1963- Institute of Electrical and Electronics Engineers Grid-forming inverters Hopf oscillator Unbalanced-voltage compensation