DC microgrids look attractive in distribution systems due to their high reliability, high efficiency, and easy integration with\nrenewable energy sources. The key objectives of the DC microgrid include proportional load sharing and precise voltage\nregulation. Droop controllers are based on decentralized control architectures which are not effective in achieving these objectives\nsimultaneously due to the voltage error and load power variation. A centralized controller can achieve these objectives using a high\nspeed communication link. However, it loses reliability due to the single point failure. Additionally, these controllers are realized\nthrough proportional integral (PI) controllers which cannot ensure load sharing and stability in all operating conditions. To address\nlimitations, a distributed architecture using sliding mode (SM) controller utilizing low bandwidth communication is proposed\nfor DC microgrids in this paper. The main advantages are high reliability, load power sharing, and precise voltage regulation.\nFurther, the SM controller shows high robustness, fast dynamic response, and good stability for large load variations. To analyze\nthe stability and dynamic performance, a system model is developed and its transversality, reachability, and equivalent control\nconditions are verified. Furthermore, the dynamic behavior of the modeled system is investigated for underdamped and critically\ndamped responses. Detailed simulations are carried out to show the effectiveness of the proposed controller.
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