An Efficient Equilibrium Strategy Based on the Energy Transfer Among Arbitrary Cells
Liu Zhengyu1,2, Yan Peng1, Wu Yinhang1, Xu Yajuan1
1. School of Mechanical Engineering Hefei University of Technology Hefei 230009 China; 2. Engineering Research Center of Safety Critical Industry Measurement and Control Technology of Ministry of Education Hefei 230009 China
Abstract A novel efficient equilibrium strategy was proposed based on the direct transfer of energy equalization topology among arbitrary cells. The safety coefficient was adopted to redefine the partition of battery state according to the charge-discharge characteristic curve of cell. Then the attribute function of battery remaining capacity and segmented threshold correction factor function were set. Theoretical derivation method was used to find out the changing laws of searching threshold center. Taking the average remaining capacity of the battery as the starting searching point, an efficient way called pre-search was used to quickly determine the searching orientation and the optimal starting value. The transformation matrix and transfer process model were established, and linear programming idea was used to solve the optimal path of energy transfer. In this strategy, the remaining capacity was set as the equilibrium indicator to carry out a comparison experiment of charge-discharge equilibrium on six lithium-ion cells in series. The experimental data show that this scheme can achieve equilibrium target with higher efficiency and lower power consumption, thereby effectively improving the performance of the battery.
Liu Zhengyu,Yan Peng,Wu Yinhang等. An Efficient Equilibrium Strategy Based on the Energy Transfer Among Arbitrary Cells[J]. Transactions of China Electrotechnical Society, 2019, 34(21): 4572-4579.
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2019, Vol. 34 
