Distributed Adaptive Power Management for Islanded DC Microgrids: A Case Study for Medium Voltage Ship Power Systems

The growing incorporation of renewable energy sources into the traditional utility system has led to the development of microgrids to efficiently supply power to areas localized at the renewable sources. Similar systems are being developed for power distribution on future navy ships to effectively incorporate advanced systems requiring DC power, though such systems do not contain renewable energy resources, they do however contain load structures that present major challenges to grid stability and functionality. These DC microgrids for naval applications thus require management of power flow throughout the system, and therefore require advanced controls to accurately regulate and stabilize the systems during changing operational conditions. Therefore, adaptive droop control is proposed as a power management layer for these DC microgrids. This method uses adaptation of the controller parameters to account for uncertainty and changes in the system to accurately regulate the power sharing among distributed generation sources and to stabilize the bus voltage of the system. The proposed method is applied to a notional medium voltage direct current (MVDC) ship power system and demonstrated through an operational scenario to test the effectiveness of the control algorithm utilizing controller hardware in the loop.