Electro-Thermal, EMI and Reliability Assessment of Post-800 V Traction Inverter Topologies

Abstract

The transition toward electric vehicle (EV) architectures exceeding 800 V offers key advantages, including shorter charging times, lower operating currents, and reduced system weight due to smaller conductor cross-sections, all of which enhance overall vehicle performance. However, identifying suitable traction inverter topologies that meet automotive requirements for efficiency, electromagnetic interference (EMI), and reliability remains critical. This study presents a simulation-based converter-level electro-thermal and conducted-EMI benchmark of 2-Level H-Bridge, 3-Level Active Neutral-Point Clamped (ANPC), and 3-Level T-Type inverters under identical output-power operating conditions. The distinguishing feature of this work is the unified evaluation of these topologies under a common external thermal boundary, enabling a consistent comparison of semiconductor losses, junction-temperature behaviour, cooling-burden indicators, conducted-EMI tendencies, and first-order lifetime-oriented thermal indicators. Within this framework, the required effective thermal resistance is used as a cooling-burden indicator, while junction-temperature swing and mean junction temperature are used as relative thermal-stress indicators. Under the considered simplified R–L loading conditions, the results show that multilevel topologies reduce semiconductor losses, peak junction temperature, conducted-EMI excitation, and relative thermal-stress indicators compared with the 2L H-Bridge. These findings are interpreted as comparative topology-level trends under the defined converter-level simulation framework rather than as final vehicle-level EMI compliance or power-module lifetime predictions.