A Novel Step-up Converter Based on Active Network and Coupled-Inductor Technique with Soft Switching Operation

Abstract

Step-up converters having high voltage gain are one of the essential parts of renewable energy systems. Because the renewable energy systems' output voltage is low, dc-dc converters are generally utilized to produce high output voltage for industrial applications. There are many structures for boosting voltage, such as switched-capacitor (SC) or switched-inductor converters and using transformers. However, each of these converters has some drawbacks, such as high current or voltage spikes on power switches or diodes, transformer leakage inductances, and low efficiency. Combining the coupled-inductors and clamp circuits is a suitable solution to overcome high current and voltage spikes caused by stray inductances. This paper proposes a new soft-switching step-up converter based on an active network and coupled-inductor technique. Zero voltage switching (ZVS) of the main power MOSFETs reduce switching losses and EMI noises and increases the converter efficiency. Consequently, high switching frequency operation is possible to achieve high level of power density. The converter is simulated for wide output power (100 W-1 kW) and wide input voltage (40 V -100 V) to regulate the 400 V output voltage.