|The 46 kW hub motor. Click to enlarge.|
BluWāv Systems LLC, a provider of hub motors, electric propulsion and energy systems for the military, commercial, automotive and industrial markets, exhibited its Roadrunner four-wheel electric drive system applied in a military vehicle at the 2008 SAE Hybrid Vehicle Technology Symposium in San Diego this week.
BluWāv was formerly WaveCrest Laboratories, the developer of the dynamically reconfigurable Adaptive Motor system, which consists of a multiple-phase, DC brushless motor arranged such that the rotor surrounds and rotates around the center-mounted stator, rather than rotor rotating within the outer stator. (Earlier post.)
The WaveCrest stator consists of a series of independently controlled electromagnets driven by a proprietary power electronics module. The electromagnetic cores are identical and isolated.
The RoadRunner system as shown on a 1,500kg off-road military vehicle uses four 46kW (peak) Adaptive Motor hub motors combined with a 5.1 kWh Li-ion battery pack with A123Systems cells to support an electric range of 15 miles (25 km) with a top speed of 75 mpg (121 kph).
The hub motors provide 20 kW of continuous power, with 620 Nm of continuous torque and 1,100 Nm of pea torque. Speed range is 0-900 rpm reversible.
The motor was designed to package into a 17” rim and integrates the hub (and wheel bearings), a disk brake, and motor into a single unit. Four of these motors are capable of propelling a medium-sized automotive vehicle up to 90 mph and up a 30% grade, according to the company. The motors also provide regenerative braking for increased vehicle range, shorter stopping distances, and reduced brake wear.
The motor is a brushless DC, permanent magnet with an integrated gear set, hub, and brake. The power electronics are IGBT-based with an integrated DSP for motor control. BluWāv develops the motor, vehicle control module and pack and battery management system itself.
In January, BluWāv announced that the recently-passed Fiscal Year 2008 Omnibus Appropriations Bill directs $1.2 million to the company to accelerate its research and develop an energy storage system for hydrogen-based and hybrid vehicles.
The system is to take advantage of the unique attributes of fuel cell start, run, and shut down sequences, provide a vehicle with an electric-only range compatible with a majority of commuter drive cycles, and focus on energy absorption through regenerative braking by incorporating electric drives using the latest BluWāv brushless DC motor technology.