Energy Storage Science and Technology ›› 2022, Vol. 11 ›› Issue (1): 147-155.doi: 10.19799/j.cnki.2095-4239.2021.0374

• Energy Storage System and Engineering • Previous Articles     Next Articles

Research on hybrid energy storage power distribution strategy based on parameter optimization variational mode decomposition

Xiaozhi GAO1(), Lei WANG1, Jin TIAN1, Jialu LIU2(), Qinghua LIU3   

  1. 1.School of Electrical Engineering, Hebei University of Science and Technology, Shijiazhuang 050000, Hebei, China, Beijing 102211, China
    2.China Special Equipment Inspection & Research Insstitute, Beijing 100029, China, Beijing 102211, China
    3.National Institute of Clean and Low Carbon Energy, Beijing 102211, China
  • Received:2021-07-23 Revised:2021-09-28 Online:2022-01-05 Published:2022-01-10
  • Contact: Jialu LIU E-mail:gaoxiaozhi@hebust.edu.cn;ljlalice@hotmail.com

Abstract:

Hybrid Energy Storage System (HESS), composed of all-vanadium flow batteries and supercapacitors, can effectively suppress wind power fluctuations. In order to improve the flexibility and safety of the energy storage system, a hybrid energy storage power distribution method based on parameter optimization Variational Mode Decomposition (VMD) is proposed. Firstly, the exponential smoothing method is used to filter the wind power according to the grid connection standard to obtain the required wind power grid flowing into grid, and the wind fluctuation power which needs to be smoothed by energy storage system is calculated. Then, the fitness function is constructed by three signal decomposition evaluation indexes,and a Sparrow Search Algorithm (SSA) is adopted to optimize the mode number K and the secondary penalty factor α for VMD algorithm. Based on the optimized values of K and α, VMD algorithm is used to decompose the fluctuating wind power and then distribute it reasonably between the batteries and the supercapacitors. Finally, a fuzzy controller is employed to optimize the state of charge (SOC) of storage device to realize the secondary distribution of HESS. Example results show that the proposed method can not only adaptively decompose the wind power fluctuation power signal, effectively suppress the wind power fluctuation, reduce modal mixing and complete the reasonable distribution of HESS power, but also optimize the charge and discharge range of energy storage equipment, avoid the occurrence of overcharge and excessive discharge of energy storage equipment, and ensure the charge state of energy storage equipment in a fixed range, which realizes the safe and stable operation of HESS.

Key words: variational mode decomposition (VMD), sparrow search algorithm (SSA), hybrid energy storage system (HESS), fuzzy control, state of charge (SOC)

CLC Number: