Abstract The collaboration of storage units can better solve the randomness and volatility of distributed power generation in DC microgrids. However, the existing hierarchical control based on the DC bus voltage signal doesn’t fully consider the coordination of multiple storage units and the insufficient capacity of islanding systems. Therefore, a coordinated power control strategy for DC microgrid and storage expansion unit based on voltage hierarchical control is proposed. In order to realize the decentralized coordination of multiple storage units under the voltage hierarchical control, the load power boundary corresponding to different operation modes of the existing microgrid is revealed firstly. Then, the improved fuzzy control and droop control based on the SOC of multiple storage units are proposed to realize the adaptive allocation of charging and discharging power. For the insufficient capacity of islanding systems, a power control strategy based on the over/under voltage controller is proposed for storage expansion units according to the capacity calculation, and its influence on the power boundary of the existing system is analyzed, to ensure the safe and reliable operation of DC microgrids. Finally, simulation and experimental results verify the feasibility and effectiveness of the proposed control strategies.
Guo Hui,Wang Fei,Gu Yongwen等. Coordinated Power Control Strategy for DC Microgrid and Storage Expansion Unit Based on Voltage Hierarchical Control[J]. Transactions of China Electrotechnical Society, 2022, 37(12): 3117-3131.
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