High-efficiency Inverter Improves Electric Motor Efficiency

Hillcrest Energy Technologies, a clean technology company developing transformative power conversion technologies and control system solutions for next-generation electrical systems, has completed initial internal testing of its high-efficiency inverter with an electric motor and will release the results in an upcoming whitepaper on Thursday, April 21.
Internal tests announced previously have already confirmed the ability of the Hillcrest inverter technology to achieve efficiencies exceeding 99% at switching frequencies up to 60 kHz.
New tests were performed using the 10kW Hillcrest high-efficiency inverter proof of concept on an 80kW electric motor currently used in EV powertrain applications. After running efficiency tests on the motor to establish a performance baseline at the 10kHz switching frequency, the same tests were run at 20kHz, 40kHz and 60kHz. Results showed motor efficiency improvements at each increased switching frequency level, confirming the ability of the Hillcrest technology to leverage higher switching frequencies without generating additional losses/heat, thereby enabling the electric motor to operate at higher efficiency levels.
“Currently, electric motors used in electric vehicle powertrains operate within a switching frequency range of 8kHz to 16kHz due to the historic tradeoff between the best possible switching behavior and acceptable thermal losses,” said Harald Hengstenberger, managing director and founder of Systematec GmbH, a strategic partner to Hillcrest and current power electronics design house to the German automotive industry. “The ability of the Hillcrest high-efficiency inverter to operate at much higher switching frequencies without generating additional losses will now allow motor manufacturers to take advantage of new motor concepts not previously available to them.”
Leveraging the Hillcrest traction inverter to improve motor efficiency in an electric vehicle powertrain has the potential to reduce motor size and cooling requirements and increases power density. In an electric vehicle, this can result in more power, more payload capability and increased range.