Two‐ and three‐winding coupled‐inductor‐based high step‐up DC–DC converters for sustainable energy applications

This study proposes two configurations for a non‐isolated, high step‐up, single‐switch, coupled‐inductor‐based DC–DC converter. A coupled inductor and voltage multiplier cells are used in the presented topologies to obtain a high voltage gain. Also, a passive clamp circuit is applied in the topologies to reduce voltage stress of the main power switch. This leads to utilising a power switch with lower on‐state resistance, which decreases the conduction loss. Several advantages such as low operating duty cycle, high voltage conversion ratio, reduced voltage stress of semiconductors, low turn ratio of the coupled inductor, leakage inductance energy recovery and high efficiency operation make the presented structures appropriate for sustainable energy applications. The operational principle and steady‐state analysis of the suggested topologies in continuous conduction mode are expressed in detail. Also, design procedure and theoretical efficiency of the topologies are presented. Then, the suggested topologies are compared with several similar high step‐up topologies to prove their advantages. Finally, the performance and feasibility of the proposed DC–DC converter configurations are confirmed through experimental measurement results of 29 V input and 435 V/213 W and 480 V/238 W output laboratory prototypes at 50 kHz switching frequency.