Analysis, design, and reliability evaluation of a modified multi-port quasi-resonant converter with high gain

High-gain converters play a vital role in all industrial applications such as automobiles, motor drives, renewable energy systems, and railway transportation sectors. The conventional converters have low gain owing to high-voltage stress on active MOSFET, diode and low efficiency related with high operating pulse ratio. To overcome the limitations associated with the conventional converters, this study proposes a non-isolated configuration of multiport quasi-resonant converter (MP-QRC) with high gain. The proposed MP-QRC has the merits of high-voltage gain, reduced number of components, minimum conduction losses, realization of soft switching in the devices and improved reliability. Moreover, the proposed converter is scalable and can serve as a good candidate in microgrid environment where the integration of more than one input is essential. In this paper, first a comprehensive analysis of various operation modes and design constraints are presented. Further, the study is supported with a reliability evaluation of proposed converter based on component failure. Also, the futuristic behaviour of MP-QRC under continuous conduction mode as a function of operational and environmental variables is investigated to ascertain the reliability. The steady-state operation of the converter is demonstrated for off-board electric vehilce (EV) charging using MATLAB/SIMULINK and experiments performed on a 300-W test rig.