A novel transformer-less battery charger for hybrid fuel-cell/photovoltaic electric vehicles based on a new dual-input high step-up DC-DC converter

The hydrogen fuel cell is one of the latest technologies used in fuel cell electric vehicles (FCEVs), which uses hydrogen gas to supply the electrical energy needed by the electric engines. The proposed topology has boost function and uses a novel diodes and switches network, which leads to the creation of an integrated system with high efficiency and high voltage gain. Other advantages of the proposed converter are small size, low voltage and current stresses on all the components, less component count, continuous input current and light weight; which makes it more efficient compared to existing structures. In this regard, theoretical calculations and steady state analysis for the proposed system have been presented. Also, in order to verify the performance of the proposed converter, it has been simulated in the MATLAB/Simulink software environment at the rated power of ۱kW, with an output voltage of ۲۲۰V and an output current of ۴.۵۵A, and the results have been presented in detail. The peak efficiency of the proposed converter reached ۹۷.۴% at half power, and the efficiency at rated power was reported ۹۶%. Moreover, in the proposed structure, the voltage stress of capacitors, diodes and switches reaches the maximum value of ۶۳%, ۸۳% and ۴۱% of the output voltage, respectively; which are promising values. Finally, to verify the performance of the proposed converter and the relationships obtained, a ۱kW prototype is built in the laboratory to demonstrate the efficiency of the proposed converter.

Keywords:

Battery , Charger , DC-DC Converter , Electric vehicles , Fuel Cell , Photovoltaic