This paper compares three different dc-dc topologies, i.e. boost converter, three-level flying capacitor multilevel converter (FCMC) and one-cell switching tank converter (STC) for a 100 kW electric vehicle power electronic system. This bidirectional dc-dc converter targets 300 V - 600 V voltage conversion. Total semiconductor loss index (TSLI) has been proposed to evaluate topologies and device technologies. The boost converter and one-cell STC have been fairly compared by utilizing this index. The simulation results of a 100 kW one-cell STC working at zero current switching (ZCS) mode have been provided. A 100 kW hardware prototype using 1200 V 600 A SiC power module has been built. The estimated efficiency is about 99.2% at 30 kW, 99.13% at half load, and 98.64% at full load. The power density of the main circuits is about 42 kW/L
Development of a 100 kW SiC Switched Tank Converter for Automotive Applications
A 300 V to 600 V 100 kW SiC MOSFET based one-cell switched tank converter (STC) is developed as a bidirectional dc-dc power transfer stage between the vehicle battery and the DC-link side of the vehicle dc-ac inverter. A continuous half-load 50 kW and short-period full-load 100 kW operation is targeted. Working principles of the proposed topology are analyzed. Design of the key components such as SiC MOSFET power modules, AC resonant capacitor and inductor is presented. A 100 kW prototype has been assembled and tested. An energy-efficient test platform is designed. The power density of the main power processing part is around 41.7 kW/L. The tested peak and full-load efficiencies are about 98.7% and 97.35%, respectively. The thermal performance has also been evaluated. Both the tested electrical and thermal results are consistent with the theoretical design.
- Award ID(s):
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- 2019 IEEE Energy Conversion Congress and Exposition (ECCE)
- Sponsoring Org:
- National Science Foundation
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