Command-Filtered Backstepping Controller for DC Microgrid with Hybrid Energy Storage Devices

This paper presents a control scheme for command filtering and backstepping for DC microgrid systems with hybrid energy storage devices. The proposed control scheme strictly controls the active power output by each power converter unit (PCU), and stabilizes the DC bus voltage, regardless of load transients. In terms of power distribution, the energy management system performs first-order low-pass filtering according to the required compensation power, where the high-frequency part is borne by the supercapacitor and the low-frequency part is borne by the battery. As to design of the controller, The use of backstepping control easily lead to differential expansion, which makes the design of the controller difficult. The command filter is used to solve this problem. Finally, the simulation is set up in Matlab/Simulink environment. The simulation results show that the designed power distribution strategy and controller have excellent control effect and strong robustness.