A Comprehensive Review on DC Microgrid Controlling Techniques

Nowadays, power systems are shifting towards the DC electrical nature to effectively integrate with the green energy resources. Yet, most of the renewable energy sources are used with the AC grid, which has high power conversion losses. These losses can be minimized using various DC grid controlling techniques based on the network architecture, mathematical model, controlling elements, and hierarchy level of control. Control techniques are used in DC microgrids to mainly manage the power flow, voltage, and frequency of the system. This article outlined primary control for voltage and current regulation; secondary control for error correction in voltage, current, and power sharing in microgrids and their clusters; and tertiary control for power and energy management. It presents a detailed survey of the issues generated by the DC microgrid and a classification of the controlling techniques, which will be helpful for further improvement in the functioning of the standalone DC microgrid.