Analysis, Design, and Hardware Implementation of a Novel Isolated DC‐DC Converter for Medium‐Power Electric Vehicle Battery Charging

ABSTRACT The rapid depletion of fossil fuels in recent decades has drawn global attention to the need for renewable energy sources. In addition, electric vehicles (EVs) are gaining importance as they are the cleanest form of transportation, contributing to the reduction of pollution and global warming. EV batteries require DC energy to charge. Renewable energy‐powered charging is an environmentally friendly and increasingly feasible method for meeting energy needs while minimizing the negative environmental effects of transportation and electricity production. It is anticipated that the use of renewable energy technology will significantly impact global energy and transportation systems in the future due to its ongoing improvements and decreasing prices. This research introduces a novel approach to developing and implementing an isolated DC‐DC converter with a single‐stage power conversion. To synthesize the proposed isolated DC‐DC converter, a MOSFET H‐bridge, a high‐frequency transformer, and a bridgeless Luo converter were combined, considering the input‐parallel‐output‐parallel (IPOP) configuration. Bridgeless Luo converters significantly reduce the conductive and switching losses of the semiconductor by replacing the full‐bridge diode rectifier. This work details the operating modes of the proposed isolated DC‐DC converter, along with the corresponding dynamic equations. Further, the average large signal and steady‐state models are detailed to obtain the design of storage elements for the desired specifications. The system under consideration is simulated, and waveforms depicting the voltages and currents of various components are provided. A prototype with a 100‐W power output is created to test the performance of the proposed converter to charge a lithium‐ion battery at a voltage of 48 V. The loss components in the converter are analyzed, and the energy buildup in the battery during the hardware implementation is also presented. Silicon carbide (SiC) MOSFETs and diodes are employed in the prototype to enable high switching frequency operation leading to reduced size and weight of the components. The proposed converter is seen to be a novel isolated DC‐DC converter with low output ripples and lower losses, suitable for medium‐power EV battery charging.