Abstract：In view of the un-uniformity with each cell of series-connected traction battery bank in a serial charging scheme, a charge equalization circuit with inductor symmetrically distributed is proposed. The operating principle and equalizing process are analyzed in detail in this paper. Taking advantage of the relationship between the terminal voltage of battery and the state of charge (SOC) based on the reactive battery circuit model, the duty ratio of switching device in the charge-equalizing circuit can be calculated and the uniformity of SOC in each cell should be implemented during charging-time. It is confirmed by the experiment that the energy among the batteries could be dynamically transferred with this method. As a result, this means make up the un-uniformity of battery and improve the performance as well.
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2010, Vol. 25 
