An asymmetrical PWM (APWM) controlled multi-input isolated resonant converter with zero voltage switching (ZVS) for hybrid renewable energy systems

This paper proposes a multi-input isolated resonant converter topology that is able to maintain ZVS for a wide range of load conditions for hybrid renewable energy systems. Each of the input stage of the proposed converter consists of an asymmetrical pulse-width modulation (PWM) controlled halfbridge resonant converter. An output filter is then shared among the input resonant converter modules; with the output inductor operates in continuous conduction mode (CCM) to provide almost constant current to the load. The APWM controlled switch pair in each of the input stage is controlled independently, so that the proposed converter is capable to support individual or simultaneous operations of the input sources. The operating principles of the proposed circuit and its key theoretical waveforms will be explained in this paper. To validate the functionality of the proposed circuit, results will be provided on a 70 kHz, 1kW system.