Fuzzy Logic Based Droop Control of Bipolar DC Microgrid using Novel SEPIC-Cuk Converter

Bipolar DC microgrids (BDCMGs) are susceptib1e to voltage imbalance resulting from uneven load distribution between the two poles, thereby affecting and reducing the reliability and efficiency of the system. To enhance voltage stability and effective load sharing between resources, it is necessary to mitigate the voltage imbalance problem. A decentralized control architecture allows the system to operate effectively while ensuring overall stability and performance. This paper introduces a novel combination of the SEPIC-Cuk converter topology, enabling power from multiple sources to be fed into the three-wires system of BDCMGs, thereby minimizing the total count of DC-DC converters in the system. For the proposed topology, a droop-based fuzzy logic algorithm is implemented using the Takagi-Sugeno approach, which adapts to dynamic conditions and adjusts droop coefficients based on linguistic rules to optimize power distribution and system stability. Additionally, physical-layer communication is utilized to exchange control information via modulated power signals, eliminating the need for external communication links. Comprehensive simulations and verifications under various load conditions validate the effectiveness of the proposed topology and the control method. Compared with other conventional methods, the novel topology with the fuzzy logic controller achieves a notable improvement, enhancing system efficiency by 3% and reducing response time by 2%.