Constant Magnetizing Current Battery Equalizer Based on Multi-Winding Transformer

Automatic battery equalizer has the characteristics of low cost. However, due to the lack of signal feedback in the automatic battery equalizer, self-regulation and topology protection are seriously inadequate. In this paper, a new method based on multi-winding transformer that can achieve constant magnetizing current balancing with a current sensor is proposed. By adjusting the duty cycle of switches (MOSFETs), the constant magnetizing current is controlled, which can achieve fast balancing speed while ensuring circuit safety and reducing cost. The equalizer has multiple modes such as Cell to Cell (C2C), Cell to String (C2S), and String to String (S2S), and the equalizer can be switched in different modes by controlling the MOSFETs.