A DC-DC converter plays a vital role in the On-Board Charger for Electric
Vehicles (EVs). Also, having the capability for bidirectional power flow for
a DC-DC converter is essential for EVs to transfer power from
Vehicle-to-Grid (V2G) and Vehicle-to-Vehicle (V2V). In this context, this
paper proposes a bidirectional DC-DC converter for the On-Board Charger for
Electric Vehicles (EVs). The proposed DC-DC converter has two paths: a lossy
partial path through two bridges, a high-frequency transformer, and a
lossless direct path directly connecting the source to the output. A 7.8 kW
DC-DC converter is developed in MATLAB/Simulink. The performance of the
converter is analysed for various operating scenarios. Further, a
scaled-down hardware prototype of the proposed converter with a power rating
of 600 W has been developed. The dSPACE controller is used to control the
power flows. The prototype is tested under various operating conditions. The
experimental and simulation results show that the power flow through the
direct path is around 58 % and through the partial path around 42 %. Due to
this, the overall converter efficiency of 97.8% during charging and 95.6 %
during discharging cycles has been achieved. Also, as only 42 % of power
flows through the partial path, all the components' ratings and sizes are
significantly reduced. Also, the distinguishing feature is its bidirectional
power flow capability, making the EV capable of V2V and V2G power transfer.
Hence, the proposed DCDC converter is an efficient and compact solution for
an On-Board Charger for EVs.