PUBLICATIONS

 This paper presents the sensorless control of interior permanent magnet synchronous motor (IPMSM) for the wide-speed-range operation of railway traction motors. For the low speed range, a continuous high frequency signal injection is applied to the motor to extract the rotor position by the signal processing method using the measure axis. For the middle and high speed range, the rotor position is estimated by using the disturbance observer based on the extended back electro-motive-force (EEMF) model. The previous transition algorithm between two speed ranges is carried out at a specific operation point for the wide-speed-range operation. Such transition algorithm, however, could change the speed transition point due to the parameter variations of IPMSM and occur the speed overshoot during the load changes. Therefore, this paper proposes a new and simple weighting function for the stable transition operation between two speed ranges. The experiments are carried out to show the effectiveness of the proposed algorithm.