The latest application of Protean Electric’s in-wheel electric motor technology has made its US debut at the Management Briefing Seminar in Traverse City, Michigan, where Protean has demonstrated its wheel motors in a front-wheel-drive Vauxhall Vivaro diesel-electric hybrid light commercial vehicle.
Protean Electric outfitted the front-wheel-drive Vivaro with two Protean Electric PD-18 motors attached to the rear axle. The two motors together provide torque assist of up to 1,180 lb.-ft. (1,650Nm) peak and 740 lb.-ft. (1,000Nm) continuous at the rear wheels.
The van was also equipped with a 21 kWh battery, giving it a range of 55 miles. While operating in hybrid mode, the Vivaro managed 114 mpg on the New European Drive Cycle — over three times the fuel economy of the standard vehicle.
The system can also deliver regenerative braking on the rear wheels with no modifications needed to the existing front brakes while retaining the vehicle’s original engine and drive system. This high level of regenerative braking allows manufacturers to use a smaller battery size or extend the range with the same battery size.
The Vivaro retrofit also allows the driver the unique advantage of being able to switch between multiple operating modes: two- or four-wheel drive operation, IC engine-only drive, electric-only drive, or an electric torque assist Through-The-Road-Hybrid.
The vehicle underwent a rigorous testing regime jointly conducted by Millbrook and Protean Electric. Work is now underway to build a Vivaro Plug-In Parallel Through-The-Road-Hybrid test fleet for select fleet customers.
Protean claims its patented direct-drive design ‘bolt-on hybrid’ system has the highest torque and power density of any electric propulsion system. The design has the rotor on the outside and the motor control electronics and regenerative braking on the inside of each motor assembly. Each Protean Drive in-wheel motor can deliver 110hp (81kW) and 590 lb.-ft. (800Nm), weighs only 31kg (68lbs), and fits within the space of a conventional 18-inch road wheel.
Michelin has been showing off versions of the “Active Wheel” since 2004. The system contains virtually all of the components necessary for a vehicle to propel or stop: an electric motor, suspension coils and springs, and braking components.