Fuzzy proportional-resonant control strategy for three-phase inverters in islanded micro-grid with nonlinear loads

Abstract

Conventional proportional-resonant controller is widely accepted and adopted in micro-grid applications. However, it's hard to design a satisfactory conventional proportion-resonant controller due to the contradictory nature of the inverter's stability, dynamic response speed and static tracking accuracy. Therefore, some trade-off strategies proposed in previous works are usually favored. This paper proposes a novel fuzzy proportional-resonant control strategy for a three-phase inverter, which can obtain better outcomes of three contradictory performance characteristics simultaneously. The detailed mathematical models and design procedure of the controller for the studied inverter are also presented. Compared with conventional proportional-resonant control strategy, the superiority of the proposed fuzzy proportional-resonant control strategy is significant for its better system stability, faster dynamic response speed and higher static tracking accuracy. Results from simulation are provided to verify the feasibility and effectiveness of the proposed approach.