General Requirement of Traction Motor Drives

This chapter presents the general requirement of traction motor drives. Differences between traction motors and industrial motors are discussed. Classification of traction motors is given and characteristics of each type of motors namely DC (direct current) motor, induction motor, permanent magnet (PM) motor, PM hybrid motor, and switched reluctance motor are discussed and evaluated. The newly developed stator-PM machines are also introduced. Design consideration of traction motors is described with emphasis on sizing equation, selection of electric and magnetic loadings, speed ratings, and so on. Moreover, system-level consideration in traction motor design, including single or multi-motor configurations, fixed- or variable-gearing transmissions, geared or gearless, voltage level, and so on, are also presented. Power devices and power converters for traction motor drives are discussed and evaluated. Control strategies for traction motor drives, including field-oriented control (FOC), direct torque control (DTC), artificial intelligent control (AIC), and position-sensorless control (PSLC), are presented and compared. Keywords: traction motor drive; general requirement; DC motor; induction motor; permanent magnet motor; switched reluctance motor; power converter; control; FOC ; DTC