Development of Wheel Mounted Direct Drive Traction Motor for Rail Vehicle

Abstract

In the conventional rail vehicle, traction motor is mounted on the truck frame, and the shaft torque is transmitted to the wheel set via flexible coupling and reduction gearing. The reduction gearing is effective to increase the torque, but gives rise to maintenance, noise and transmission loss. To overcome these problems and simplify the truck structure, we conceived an idea of wheel mounted direct drive traction motor system without the reduction gearing, and started the development. In this system, the traction motor is required to produce more torque and reduce the mass. So we introduced permanent magnet synchronous motor for the first time in the rail vehicle. Here, we propose fundamental structures of the wheel mounted direct drive traction motors, and present a prototype wheel mounted traction motor model, which is manufactured by trial as the first step of the development. We overcame the problem of temperature rise of permanent magnet, through analysis and improvement of the magnetic structure. © 2001, The Institute of Electrical Engineers of Japan. All rights reserved.