Acura will run an all-electric, NSX-inspired EV Concept in the Electric Modified Class at the 2016 Broadmoor Pikes Peak International Hill Climb. The Acura EV Concept features a further evolution of the experimental, all-electric, 4-motor Super Handling All-Wheel Drive (SH-AWD) powertrain that won last year’s Pikes Peak Challenge Exhibition class. Acura will field two production NSX supercars in the event as well.
The Acura EV Concept will be driven by Tetsuya Yamano, who campaigned last year’s CR-Z-based electric prototype. The all-wheel-drive electric SH-AWD powertrain enables four-wheel independent torque allocation. The Acura EV Concept’s Electric SH-AWD powertrain produces three times the total system output of last year’s electric prototype and is mated to the NSX body.
The production SH-AWD is a three-motor hybrid system designed for a sports car and offers high power, lightweight and high response, with high cooling performance for high-load operation such as circuit driving.
The three-motor SH-AWD system features a midship-mounted V6 twin-turbo engine; the direct drive motor of a hybrid system mounted directly on the engine; and a 9-speed dual-clutch transmission (DCT). The front wheels are driven by a twin-motor unit (TMU).
The E-Drive system uses the three motors to enhance cornering performance by torque vectoring and front/rear traction force allocation. Direct acceleration response is achieved by a constant assist according to the accelerator position (AP) utilizing the twin-motor unit (TMU) and compensating lack of low speed torque of the turbocharged engine with the direct drive motor and the high-power battery.
The SH-AWD TMU consists of two independent motors, planetary gear sets and a brake. The TMU can freely allocate the right/left torque in any speed region.
Honda R&D has been developing “super handling” technology for more than 20 years in the pursuit of ideal vehicle handling. By applying separate Twin Motor Units (TMUs), the brains of Sport Hybrid SH-AWD, on each axle in the new EV Concept, Acura is enabling independent torque vectoring to all four corners. Based upon the learnings from last year’s race, the team updated the system management of the powertrain for more precise thrust at each wheel.
Acura’s Sport Hybrid SH-AWD technology utilizes the highly responsive acceleration characteristics and regeneration capability of electric motors to advance the torque vectoring systems currently applied to NSX, and available on RLX and the upcoming 2017 MDX.
The system enables ideal handling characteristics in various driving situations by coordinating and managing all dynamic systems, including Electronic Power Steering (EPS), Vehicle Stability Assist (VSA) and Sport Hybrid SH-AWD.
Tamura, S. and Yoshinari, T. (2016) “Development of Electric Drive System for New Model Super Sports Hybrid Vehicle,” SAE Technical Paper 2016-01-1685 doi: 10.4271/2016-01-1685