Citation: Sayed, K.; Abo-Khalil, A.G. An Interleaved Two Switch Soft-Switching Forward PWM Power Converter with Current Doubler Rectifier. Electronics 2022, 11, 2551. https://doi.org/10.3390/ electronics11162551 Academic Editors: Xiaodong Li, Hao Chen and Thirumarai- Chelvan Ilamparithi Received: 4 July 2022 Accepted: 9 August 2022 Published: 15 August 2022 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affil- iations. Copyright: © 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https:// creativecommons.org/licenses/by/ 4.0/). electronics Article An Interleaved Two Switch Soft-Switching Forward PWM Power Converter with Current Doubler Rectifier Khairy Sayed 1, * and Ahmed G. Abo-Khalil 2,3 1 Faculty of Engineering, Sohag University, Sohag 82524, Egypt 2 College of Engineering, University of Sharjah, Sharjah 27272, United Arab Emirates 3 Department of Electrical Engineering, College of Engineering, Assiut University, Assiut 71515, Egypt * Correspondence: khairy_sayed@eng.sohag.edu.eg Abstract: Forward converters have been broadly used in the power supply industry due to their simplicity, worthy efficiency, and low cost. A novel prototype soft-switched zero-voltage and zero- current ZVZC PWM DC-DC power converter with low voltage/current stresses is introduced for telecommunication power feeding in this paper. A new two-switch interleaved forward converter cir- cuit is introduced to minimalize current circulation with no supplementary auxiliary snubber circuits. This converter circuit includes some outstanding benefits such as reduced components, improved efficiency, high power density and economic circuit configurations for high power conditioning applications. The simple operation principle is demonstrated on the basis of steady-state analysis. Furthermore, the effective feasibility of the proposed circuit topology is evaluated and verified practically for a 500 W–100 kHz prototype breadboard. The operation principle and steady-state characteristics are demonstrated from a theoretical point of view. To verify the practical effectiveness of the proposed power converter, a 500 W–100 kHz prototype converter using ultrafast IGBTs is im- plemented for a distributed telecommunication energy plant. The studied soft-switching converter is evaluated in comparison with the previously-proposed PWM converters in terms of voltage, current stresses, and operating efficiency. Keywords: DC-DC power converter; modified forward converter; high-frequency link; soft-switching PWM interleaved converter; ultrafast IGBT; telecommunication applications 1. Introduction There is an increasing need to achieve higher power densities and efficiencies for power converters. This has increased the use of soft-switched converters due to the benefits of primary switch zero-voltage switching (ZVS) turn-on and zero-current switching (ZCS) turn-off [1]. In particular, half-bridge or full-bridge-based LLC technology [2,3], which is more suitable for medium to high power applications, is broadly used in practical designs. Energy efficiency and power density are very important features of today’s consumer electronics and industrial applications. In addition, high efficiency over a wide range of output power and the ability to operate over a wide input voltage range are important future prospects for DC-DC converters. To achieve high efficiency, it is necessary to reduce switching loss, especially in high frequency power converters. In addition, for light loads where switching loss and gate drive loss dominate [4,5], reducing switching loss is effective in achieving high efficiency. On the other hand, for relatively low power applications such as for PV systems with low power or auxiliary power in electric vehicles, a forward converter is usually recommended due to the simplicity of the design [4]. According to this, some studies on forward type resonant converters were carried out [4–8]. Operation at hard switching of the flyback and forward converters imposes high voltage and current spikes on their switches, due to presence of transformer leakage inductance. Furthermore, switching losses result in low conversion efficiency. A passive Electronics 2022, 11, 2551. https://doi.org/10.3390/electronics11162551 https://www.mdpi.com/journal/electronics