A review of isolated bidirectional DC-DC converters for onboard EV chargers: topologies, trends, and technological suitability
Engineering Science and Technology, an International Journal, cilt.82, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Derleme
- Cilt numarası: 82
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.jestch.2026.102493
- Dergi Adı: Engineering Science and Technology, an International Journal
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, INSPEC, Directory of Open Access Journals
- Anahtar Kelimeler: Bidirectional onboard chargers, Isolated DC–DC converters, Wide voltage range
- Ankara Yıldırım Beyazıt Üniversitesi Adresli: Evet
Özet
The proliferation of electric vehicles (EVs) and the growing adoption of vehicle-to-grid (V2G) technology have established onboard chargers (OBCs) as critical interfaces between the power grid and EV battery systems. Among the constituent power conversion stages, the isolated bidirectional DC–DC converter is pivotal, as it must simultaneously provide galvanic isolation, support bidirectional energy flow, and maintain high efficiency across a wide output voltage range encompassing both 400 V and 800 V battery architectures. This paper presents a systematic review of isolated bidirectional DC–DC converter topologies for OBC applications, covering Dual Active Bridge (DAB), Inductor-Inductor-Capacitor (LLC), Capacitor-Inductor-Inductor-Capacitor (CLLC), and reconfigurable and two-stage configurations. Each topology is analyzed with respect to its operating principles, soft-switching capability, control strategies, voltage gain flexibility, and suitability for V2G operation. A comparative assessment categorizes the design strategies employed to extend the output voltage range, including variable DC-link control, topology reconfiguration, two-stage cascaded architectures, and hybrid modulation schemes. The role of wide-bandgap (WBG) semiconductor technologies—specifically silicon carbide (SiC) and gallium nitride (GaN)—in enabling high-frequency, high-efficiency converter designs is also examined. Key design requirements, regulatory standards, and recent industry trends are addressed. The findings indicate that CLLC resonant converters and reconfigurable topologies are the most promising options for next-generation bidirectional on-board chargers (OBCs). They offer an excellent balance of efficiency, wide voltage adaptability, and compatibility with both 400 V and 800 V battery platforms.