Proportional current sharing, voltage restoration, and SOCs balancing after ensuring system stability are the leading vital challenges of DC microgrid control algorithms. These aims obtain easily if the control method is implemented based on the communication links and a central controller. However, microgrids under such a control system will encounter many drawbacks. Besides, they are inadequate for geographically dispersed microgrids. Motivated by the above-mentioned, this paper proposes a novel communication-less control method that rectifies the main DC microgrid challenges. In this method, a capacitor and a DC/DC converter are responsible for stabilizing the system and restoring the DC bus voltage. During voltage recovery, the capacitor injects an AC signal into the DC bus. The frequency of the AC signal is set according to the capacitor voltage. All energy storage units set their current based on the frequency and their SOC such that the SOCs are balanced in case of SOCs disparity, and the current is shared properly after they have converged. The droop control is also included in the primary layer of the units to ensure system stability in the case of capacitor failure. The stability analysis proves that the proposed method profits from stability while considering the limitations of the units. As the proposed method does not rely on communication links, it is applicable to widespread microgrids. Simulation results confirm that the proposed method benefits from proper current sharing, voltage restoration, SOCs balancing, and adequate dynamic response.

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