Three-Phase Integrated-Optimized Power Electronic Transformer for Electric Vehicle Charging Infrastructure

This article proposes the high-frequency link three-phase integrated-optimized power electronic transformer (PET) for electric vehicle (EV) charging infrastructure in the distribution network. The structural elements and configuration of PET significantly affect its design and performance. However, the different topologies of PET available in the literature did not consider the influence of the circuit’s structural elements with their parasitic components. Consequently, it violates the value of control variables which fails to accomplish essential control characteristics required for EV charging infrastructure in the smart distribution network. Therefore, in this article, detailed modeling and analysis of the proposed PET are carried out at each stage by incorporating its structural effect to analyze the circuit behavior during different operating conditions. As a result, it provides the design and operating constraints for the proposed PET, employed in the design procedure and control algorithm. Furthermore, the dual-degree control (DDC) method is proposed to utilize the structural framework and dual control variables of the proposed PET to meet out significant aspects of EV charging infrastructure in the distribution network such as wide range of voltage regulation, active control over the power flow, and soft-switching operation. Finally, a 4-kW prototype of the proposed PET is built up, which has a bidirectional power flow feature and isolated dc dual-port output terminals. Hardware testing and experimental results verify the effectiveness of the proposed PET based on the DDC method.