Power Distribution Strategy of Microgrid Hybrid Energy Storage System Based on Improved Hierarchical Control

Energies

Zhiquan Tang¹  Linxin Guo²  Lujun Wang³  Tiezhou Wu³  Wenshan Yu³ 

[1] Hydropower Group Co., Ltd., Danjiangkou Hydropower Plant, Danjiangkou 442700, China;;Hanjiang Water Resources &Hubei Key Laboratory for High-efficiency Utilization of Solar Energy and Operation Control of Energy Storage System, Hubei University of Technology, Wuhan 430068, China;

关键词: distributed hybrid energy storage system (D-HESS);    improved low pass filter;    hierarchical control;    power management strategy;    Li-ion battery;    supercapacitors;   

DOI  :  10.3390/en12183498

来源: DOAJ

【 摘 要 】

Traditional hierarchical control of the microgrid does not consider the energy storage status of a distributed hybrid energy storage system. This leads to the inconsistency of the remaining capacity of the energy storage system in the process of system operation, which is not conducive to the safe and stable operation of the system. In this paper, an improved hierarchical control strategy is proposed: the first allocation layer completes the allocation between the distribution energy storage systems considering the state of hybrid energy storage systems, and the second allocation layer realizes the allocation within the hybrid energy storage systems based on variable time constant low-pass filtering. Considering the extreme conditions of energy storage systems, the transfer current is introduced in the second allocation process. The SOC (stage of charge) of the supercapacitor is between 40% and 60%, which ensures that the supercapacitor has enough margin to respond to the power demand. An example of a 300 MW photovoltaic microgrid system in a certain area is analyzed. Compared with the traditional hierarchical control, the proposed control strategy can reduce the SOC change of a hybrid energy storage system by 9% under the same conditions, and make the supercapacitor active after power stabilization, which is helpful to the stable operation of the microgrid.

【 授权许可】

Unknown