Benefits of SiC MOSFET technology in powertrain inverter of a Formula E racing car Dr.-Ing. Felipe Filsecker Application Engineer ROHM Semiconductor GmbH
ROHM SiC device development 18 years of experience Fully integrated production system Start of automotive business 2012 2015 2017 2000 2004 2009 2010 4inch World s first 6inch 3inch Trench SiC MOS 6 inch SiC SBD 2inch mass production mass production Started SiC R&D Acquired SiCrystal SiC SBD / MOS Full SiC Module SiC substrate mass production mass production World s first P. 1
Superior material properties of SiC P. 2
VGS=18V 16V 14V 12V 10V 8V 6V 4V 2V 0V What benefits can be obtained on system level? Lower resistance Smaller size / higher efficiency Si SiC Higher frequency operation Smaller passive components Si SiC Higher temp. operation Simpler thermal management Si 200 250 250 200 SiC 150 100 50 0 0 5 10 15 20 P. 3
Inverter Motor CAN Power electronics: a key technology for hybrid and electric vehicles 48 V CAN EMS CAN DC / DC converter 12 V Air compressor Pumps CAN Auxiliaries BMS HV battery LV DC HV DC U V W Steering drive Wireless charger On-board charger High power DC/DC converter Transmission EMS: Energy Management Systems BMS: Battery Management Systems AC charging station Fast charging station (DC) P. 4
Range road map of electrical vehicles To increase the e-mobility market the battery range needs to increase Solution from OEMs Batteries get bigger Range gets longer 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 ~ 140 km > 180 km > 250 km > 400 km 24 kwh > 30 kwh > 40 kwh > 70 kwh To reduce charging time Charging power has to get higher 50 kw Fast DC charging on the highway 150-350 kw 20 kw Charging at commercial places 50 kw 3-6 kw Charging at home or office 11 / 22 kw P. 5
Typical single-phase OBC (3.6 / 7.2 kw) AC input (1-3ph) Two-stage PFC Isolated DC/DC HV battery AC DC DC AC DC DC AC DC ROHM SiC devices already in use since 2012 for on-board charger systems Two-stage PFC: Booster diode: 650V SiC SBD P. 6
SiC solutions in on-board charging systems PFC SiC SBD (650V/1200V) SiC MOS (650V/30mΩ) Power shunt (2512/3W) DC/DC SiC MOS (650V/30mΩ, 60mΩ) Secondary-side rectifier SiC SBD (650V/1200V) Si Fast Recovery Diode (600V/20A) Package THT: TO220, TO247 SMT: TO252, TO263, TO263-7L P. 7
Inverter Motor CAN Power electronics: a key technology for hybrid and electric vehicles 48 V CAN EMS CAN DC / DC converter 12 V Air compressor Pumps CAN Auxiliaries BMS HV battery LV DC HV DC U V W Steering drive Wireless charger On-board charger High power DC/DC converter Transmission EMS: Energy Management Systems BMS: Battery Management Systems AC charging station Fast charging station (DC) P. 8
Technical partnership with Venturi Formula E Team Integrating ROHM's full SiC module decreases inverter size and weight 1200-V G-type module P. 9
Inverter losses 200kW Si-IGBT-based inverter Power devices : Si IGBT + Si FRD 220kW SiC-MOSFET-based inverter Power devices : SiC MOS + SiC SBD Module: ROHM SiC G type module >400W less per switch at max. power operation P. 10
Inverter efficiency 200kW Si-IGBT-based inverter Power devices : Si IGBT + Si FRD >1.3% better efficiency at Max Power operation 220kW SiC-MOSFET-based inverter Power devices : SiC MOS + SiC SBD Module: ROHM SiC G type module 1.1% better maximum efficiency P. 11
Traction inverter comparison Key achievements: Volume reduction (ca. 30%), weight reduction (6kg 40%), Higher power density (>1.5x) Inverter Si-IGBT based SiC-MOSFET based Output Power 200kW 220kW Max SW Frequency 16kHz 24kHz Weight 15.0kg 9.1kg Volume 14.3L 10.0L Power Density 14kW/L 22kW/L P. 12
Inverter Efficiency [%] Inverter efficiency (at maximum torque operation) Efficiency at maximum torque SiC MOS based @ Max Torque Si IGBT based @ Max Torque Inverter Si-IGBT based SiC-MOSFET based Output Power 200kW 220kW Inverter Efficiency 1* Inverter Efficiency 2** Max SW Frequency 98.0% 99.1% 96.9% 98.2% 16kHz 24kHz Weight 15.0kg 9.1kg Volume 14.3L 10.0L Power Density 14kW/L 22kW/L * Max efficiency ** Max Power Operation Output Power [kw] P. 13
Extending cruising distance / Reducing battery capacity Electric vehicle simulation test bench Electric drive system inclunding electric and loss model of the inverter P. 14
[N.m] [rpm] [km/h] Extending cruising distance / Reducing battery capacity Conditions 100kW automotive motor, 3-phase PWM mode Switching frequency = 16kHz Battery capacity = 33kWh, battery voltage = 750V SiC module: BSM600D12P3G001 (dv/dt <10kV/us) IGBT module: SKIM459GD12E4 Mission profile: WLTP Class 3b Results Driving distance (Battery charge from 100% to 10%) BSM600D12P3G001 176.9km +11% SKIM459GD12E4 159.3km P. 15
Economic benefits for SiC vs. Si-based Inverter SiC module + battery reduction cost vs. SiC module cost in 2025 Ref. NEDO: Secondary battery technology development roadmap 2013 Battery cost reduction with SiC power modules for batteries > 40kWh P. 16
Summary Big potential for SiC in automotive applications (OBC, DC/DC converters and powertrain inverters) ROHM SiC module is used in 220kW class traction inverter. Inverter achieves efficiency as high as 99.1% with lower volume (30% less), lower weight (40% less), and higher power density (>1.5times higher) than conventional Si IGBT based inverter. A higher efficiency inverter enables battery cost / capacity reduction thanks to the extension of cruising distance (>10%) P. 17