Hybrid Powertrain Design Continues to Evolve
SAN DIEGO --- Though hybrid powertrain design presents unique engineering challenges, advances in technology are clearing the way for further improvement.
Opal-RT Technologies Inc. underscored this opportunity when it presented its latest development in real-time hybrid powertrain simulation at the SAE Hybrid Vehicle Technologies Symposium held Feb. 1-2 in San Diego.
Since 1999, Opal-RT Technologies has provided simulation technologies to help engineers reduce the development cycle of power electronics, electric drive control, and energy management systems. Using hardware in-the-loop simulators (HIL), design engineers can use a virtual vehicle based on real-time simulation to prototype new system concepts, validate control systems, and perform initial calibration in the laboratory -- all before a prototype vehicle becomes available.
Opal-RT's HIL simulators now serve OEMs and suppliers developing hybrid electric vehicles and components throughout North America and Asia. Opal-RT's customers include AISIN, DaimlerChrysler, DENSO, Ford, GM, Toyota, and other companies and universities leading the development of hybrid powertrains and vehicles.
Technical specialists from Opal-RT brought two examples to the symposium. The first demonstration was a real-time simulation of a fuel-cell hybrid vehicle. The core of the virtual hybrid powertrain was a high-precision Permanent Magnet Synchronous Motor (PMSM) inverter model running on an HIL simulator at a time step of 10 microseconds, with an IGBT pulse capture resolution of 10 nanoseconds. The simulation provided sufficient accuracy to reproduce typical distortions caused by dead times in switching circuits.
In the second demonstration, a three-phase PMSM model was implemented in Simulink, which compiled and downloaded into a Field Programmable Gate Array (FPGA) chip for execution using the XILINX System Generator. With a 250-nanosecond time step, this chip-based simulation allows upcoming hybrid powertrain components, such as inverters and DC-DC converters with switching frequency upwards of 100 kHz, to be accurately modeled in real-time.
“As hybrid vehicles gain greater acceptance in the marketplace, Opal-RT will continue to develop technologies and practical solutions that allow design engineers to simulate more, accurately, and in real-time," said Jean Belanger, president of Opal-RT Technologies.