The traction motor is what provides the power to the vehicle’s wheels. Traction motors have been around for a long time and have been deployed in electric trains, trams and buses for a hundred years. The technology needed in these applications has been very high power with easy access to electric power (overhead lines or power rails). When looking at the family car the power comes from batteries and is a limited resource. Also the weight of the vehicle has the biggest impact on efficiency. 

 

Small, lightweight, efficient traction motors are available but at a high cost. They tend to be either AC inductance motors requiring sophisticated controllers or permanent magnet DC motors using expensive materials in the magnet design. There are many other types of motors each with their own unique benefits and drawbacks. Simple, easy to manage series wound motors are reliable and easy to control. They are economic and readily available and our current choice. We will continue to monitor the industry and will change our design when we believe the SCWARE factors are right.