Evaluation of induction motor speed sensorless control for railway vehicle traction system

This paper evaluates the control performance of a speed sensorless induction motor control method for railway vehicles traction, compared to vector control system with pulse generators as speed sensors, from the view points of flux behavior. The speed sensorless strategy is based on the rotor flux induced voltage and is expected its high performance as well vector control system with pulse generators. The control performance is verified from the viewpoint of the rotor flux, because the speed sensor is used for controlling the rotor flux with the indirect vector control strategy. This paper provides the way how to evaluate the speed sensorless control on the railway vehicle traction system. First, the proposed speed sensorless control strategy for railway vehicles is presented. Then, its basic control characteristic is evaluated by numerical simulation and further control functions that are peculiar to the railway traction application are rated by the experiments