A Critical Review on DC Microgrids Voltage Control and Power Management

Direct current (DC) microgrids are becoming increasingly important due to a number of causes, including the widespread use of DC loads, the integration of solar photovoltaic (PV) and energy storage devices (ESDs), and the absence of frequency and reactive power control issues. The control of DC bus voltage, power management, effective power split among the ESDs, and state of charge (SoC) restorations are important in a DC microgrid. However, DC bus voltage control and power management are difficult since the microgrids connect several distributed generators (DGs), loads, utility grids, and ESDs to the DC bus using power electronic converters. It is imperative to properly control the DC bus voltage and manage power among the sources and loads in order to maintain the stability and reliability of DC microgrids. DC microgrids can be controlled by employing centralized, decentralized, distributed, multi-level, and hierarchical control systems to ensure safe and secure operation. Besides, advanced control techniques, such as nonlinear, robust, model predictive, artificial intelligence, and many others, are employed. This article critically reviews two main aspects of DC microgrids: voltage control and power management. The challenges and opportunities for voltage control and power management in DC microgrids are discussed. The benefits and drawbacks of various voltage control and power management methods have been thoroughly documented, making this a great resource for industry professionals and academics alike. Technical issues related to the voltage control and power management of grid-connected and islanded DC microgrids are discussed. Key research gaps are identified, which could be filled by cutting-edge technologies. Readers will benefit from this review by learning about the current state of DC microgrids voltage control and power management and the need for further research.