A Comprehensive Analysis for High-Power Density, High-Efficiency 60 kW Interleaved Boost Converter Design for Electrified Powertrains

Abstract

High-power boost converters offer significant benefits to hybrid and electric vehicles, because higher-voltage propulsion power equates to lower motor losses. However, the converters themselves must have high efficiency and high power density in order to make the system-level trade-off beneficial. Thus, this paper presents an optimized design process of high power multi-phase interleaved bidirectional boost converters. In order to achieve a fast and accurate analysis and design, a generalized method is developed for the calculations of required phase inductance and output capacitance. In addition, a genetic algorithm (GA) optimization method is implemented for the inductor design. Using the proposed design process, a 3-phase 60 kW interleaved converter is designed and tested using paralleled SiC MOSFETS. The converter achieves peak efficiency of 99.2% at 10 kW and is >98% efficiency from 5% to 100% load. The resulting power density is 9.4 kW/L, which can be further improved to 12.2 kW/L with alternate terminal connectors.