Bidirectional Converter with Balancing Capacitor using Multi-stage FET Driving Technique

This paper proposes a bidirectional converter with balancing capacitor using multi-stage FET driving technique. The proposed converter is constructed by implementing series-connected low voltage Si-FETs in multi-stages. The balancing capacitor can average the applied voltage on FETs in the transient state of the switching operation and tackle the voltage unbalance between the series-connected FETs. The proposed driving circuit is using multi-stage FET driving technique and can drive all the series-connected FETs using only one power supply. The effect of the balancing capacitor and the proposed driving technique are clarified and presented using the circuit simulator and the converter equivalent circuit. The proposed topology improves the converter power conversion efficiency. The experimental results show that the proposed driving technique allows the bidirectional converter to achieve a maximum power conversion efficiency of 99.2%.