The EI library in London is temporarily closed, as a precautionary measure in light of the ongoing COVID-19 situation. The Knowledge Service will still be answering email queries via, and is available for live chats on this page during working hours (09:15-17:00 GMT). Our e-library is always open for members here:, for full-text access to over 200 e-books and millions of articles. We are sorry for any inconvenience.

Whisper bus carries motors in its wheels, Professional Engineering, 15 October 2003, p 12

In the Netherlands,the e-Traction company has developed an in-wheel electric motor to drive its Whisper bus. Energy is supplied from nickel-zinc batteries that are recharged through a diesel-fuelled generating set designed to kick in when required to support propulsion. Two electric motor units, known as The Wheel, provide drive to the rear wheels. A tyre is mounted on the exterior of the motor which contains permanent magnets spinning around stationary electromagnets at the centre. A torque of 3634 to 6290 N m can be generated from each 120 kW unit, giving a maximum of 13600 N m. The energy efficiency of The Wheel is claimed as 90%, and the braking is regenerative.

Abstract details

Please login to save this item