A Fuzzy Logic Based Bidirectional On-Board Charger for Electric Vehicles with Dynamic Multiphase Operation Over All Power and Voltage Level

Modern electric vehicles rely heavily on advanced power electronic devices like on-board chargers (OBCs) and DC–DC converters, which must perform reliably across a wide range of operating conditions. These systems are required to handle variations in phase number, input voltage, and battery output voltage. Meeting high-efficiency and low-cost design goals adds further complexity, especially under modern automotive standards. To address these challenges, this article proposes a novel OBC architecture capable of operating efficiently across both single-phase and three-phase configurations throughout the full output power range. Crucially, this is achieved without adding extra power components or compromising performance. A key enabler in the proposed design is the integration of fuzzy control techniques, which allow the system to adaptively manage diverse and uncertain input conditions, ensuring optimal performance. The result is a universal-charging solution using a single, cost-effective power processor block with high power density and efficiency. This paper also presents the design and implementation of an 11-kW bidirectional prototype for an 800-V battery system compatible with a 400-V (line-to-line) mains supply.