Abstract: Considering the problem of the power batteries equalization control in an electric vehicle, a kind of equalization control method which is based on voltage transformer and constant current circuit was introduced. This method meets the requirement of equalization, and avoids the neglect effect of plus voltage. And then, the whole equalization structure of equalization was also designed, and the detailed design method of voltage transformer was introduced. Furthermore, considering the nonlinear character in the battery charging processing, a kind of close loop feedback control method which is easy to realize and meet the requirement of equalization was given. The experimental result proves that the designed method can equalize the batteries.

Key words: power batteries, equalization control, voltage transformer, close loop feedback