A Novel Bidirectional DC-DC Converter With Flyback Snubber For Hybrid Electric Vehicles
Hybrid electric Vehicles combine the benefits of engine, electric motor and batteries to provide improved fuel economy. A converter is needed in hybrid Electric Vehicle for charging and discharging of the batteries. So a charging and discharging can be combined in one circuit topology known as bidirectional DC-DC converter. Here the output is completely isolated from input, so an isolated bidirectional Dc-DC converter is used. In the bidirectional DC-DC converter, there occurs overvoltage and overcurrent stress, which can be reduced by snubber circuits. Various technologies such as RCD, active clamp and flyback snubber for bidirectional DC-DC converter are compared. The bidirectional DC-DC converter with flyback snubber is explained in detail. The simulations are carried out using Simulink/MATLAB 7.6.0 (R2009b) package. The hardware is done using PIC16F877A, a microcontroller to generate the PWM pulses for the MOSFET switches so that harmonics in the circuit can be reduced.
Divya K.Nair, Elizabeth Rajan