Distributed Fixed-Time Secondary Control for DC Microgrids

DC microgrids are considered a promising system structure to integrate various distributed renewable energy sources. To effectively coordinate the integrated distributed generators (DGs), the secondary control strategy of DC microgrids is highly expected to achieve fast dynamics and fewer signal transmissions. To achieve this goal, a novel fixed-time secondary control strategy is designed to achieve a simultaneous DC bus voltage regulation and current sharing among DGs within a fixed-time. Notably, the proposed method only needs to transmit one variable to the neighboring DGs, reducing the communication traffic and benefiting an easier implementation by comparison with the latest methods. Besides, the DC bus voltage measurement is not needed in the proposed method improving system reliability. The stability of the proposed scheme is rigorously analyzed. Simulation and experimental results are provided to verify the effectiveness of the proposed strategy.