An Improved Interleaved Boost Converter with Enhanced Power Density and Efficiency Using Single Zero Voltage Transition Soft Switching Cell for Fuel Cell Electric Vehicles

This paper proposes an improved interleaved boost converter with a single zero voltage transition (ZVT) soft switching cell (IBSC) to achieve high power density and efficiency. By applying the single ZVT soft switching cell to the interleaved structure, the volume of the converter can be reduced compared to the multi ZVT soft switching cell that has a soft switching cell for each phase. Furthermore, the efficiency of the converter can also be increased because each phase can achieve soft switching regardless of the number of phases. This paper provides a detailed analysis of the operating principle based on the duty of the main switch (S_m) and the design method for resonant parameters using the equivalent circuit of S_m. To verify the feasibility, a 3 kW prototype IBSC is designed and implemented. Based on the experimental results, the volume of the soft switching converter decreased by 29.84%, while its efficiency increased by 0.4% compared to the conventional hard switching converter. Therefore, it is confirmed that the proposed IBSC has advantages in terms of power density and efficiency.