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This study presents a novel quasi‐Z‐source converter integrated isolated multiport bidirectional DC–DC converter topology for a photovoltaic (PV) powered and battery/supercapacitor buffered electric vehicle (EV). The proposed topology can provide uninterrupted power to the electric motor of EV and regain the braking energy with the capability of bidirectional power flow. The system integrates quasi‐Z‐source and H‐bridge converters with an existing switch. Thus, a four‐port converter is achieved without any need for individual converters or additional switches. Besides, the high‐gain quasi‐Z‐source converter allows the reduction of the rated voltages of the battery and supercapacitor packs, as well as allows using a high‐frequency transformer (HFT) with a low turn ratio. The isolation between ports is provided by a secondary centre‐tapped HFT. The secondary side of the HFT is equipped with a controlled full‐wave rectifier to provide bidirectional power flow. In addition, a power flow management and corresponding control scheme are suggested. The performance of the proposed system has been evaluated for different operational changes. Results show that it properly performs the power flow between the ports under steady‐state and transient conditions. The power flow capabilities and efficiency values validate the viability and effectiveness of the proposed system. [ABSTRACT FROM AUTHOR]

This study proposes a novel hybrid energy storage system (HESS) composed of a battery pack and a superconducting magnetic energy storage (SMES) for electric vehicle. Typically, the SMES has a higher power density and lower energy density than other energy storage devices, while battery has higher energy density. Thus, the overall HESS performance can be increased in power and energy density by combining SMES and batteries. The proposed HESS is designed based on bidirectional Z‐source inverter (ZSI). Compared to other SMES/battery‐based HESS topologies that are two stage designs (including DC/DC and AC/DC converters), in this topology, SMES and battery can be incorporated into the Z‐source network which results in lower cost and improved HESS performance. Furthermore, the battery converter has been eliminated due to the buck/boost feature of the ZSI. The fuzzy control method and filters are used to distribute power between the SMES and battery. This study also describes the proposed HESS performance principles and its operation in different modes. [ABSTRACT FROM AUTHOR]