Hierarchical energy management control for islanding DC microgrid with electric-hydrogen hybrid storage system

In this paper, a hierarchical state machine energy management control method based on minimum cost algorithm is proposed. This method consists two layers, the bottom layer is responsible for the control of each devices while the top layer uses state machine strategy and minimum utilization algorithm to distribute power for each micro sources. Combining the minimum utilization cost theory with the state machine control method, the control system can optimize the utilization cost and energy storage level of the electric-hydrogen hybrid energy storage system under the premise of meeting the requirements of the basic operation of the microgrid. Through the centralized management of the top layer and the control of the bottom layer, the method completes the operation target of the microgrid, thus improving the energy utilization rate and reducing the utilization cost of the system. The real time simulation is carried out through the RT-LAB semi physical system. By a 72 h online operation under actual conditions, the effectiveness of the proposed method is verified, which ensures the low cost and stability of the island DC microgrid with electric hydrogen hybrid energy system. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.