Bidirectional Converter Using Multistage FET Driving technique with voltage balance function

Bidirectional Converter with Multi-stage FETs Featuring Voltage Balance Control Function Using Variable Capacitors

“…The multi-stage FETs driving circuit shown in Fig. 1(b) charges and discharges the boot capacitor in synchronization with the switching operation of the FETs Q 1x and Q 2y (11) . Figures 3(a) and (b) show the equivalent circuit in the charging path of the boot capacitors when the converter is operated in boost mode.…”

“…In order to improve the power conversion efficiency, converters consisting of power semiconductors connected in series have been studied (6)- (11) . However, the drain-source voltages of the series-connected FETs are not exactly the same, and they suffer from voltage unbalance owing to the deviation in electrical characteristics such as parasitic capacitances.…”

“…This converter consists of multiple lowvoltage FETs connected in series, and it improves the drainsource voltage balance of the FETs using the voltage balance control function. Using a performance index FOM (figure of merit) that estimates the power losses of converters before their detailed design (11) , the effectiveness of the proposed converter configuration is shown. In the analysis, the factors of drain-source voltage unbalance are discussed using an equivalent circuit of the simplified converter.…”

Technical trend of power electronics systems for automotive applications

“…There are multiple causes of delays in turn-off timing, such as errors in parasitic elements and errors in device characteristics. 24) The influence from each parameter of the power semiconductor device in the series-connected method is analyzed in conditions of a 500 W boost chopper (input voltage V i = 100 V, output voltage V o = 200 V, switching frequency f s = 50 kHz). Each parameter of the power semiconductor device is defined as illustrated in Fig.…”