sensorless speed control methods for synrm drives suitable for traction applications, an overview

Electric motors are the most important part and one of the main consumers of traction applications. choosing a suitable electric motor will have a significant impact on the efficiency and performance of traction applications. in recent years, synchronous reluctance motor (synrm) has become an attractive option and presents promising technology due to its remarkable features. speed control and identification are one of the most important issues for synrm. conventionally, it is done by the shaft encoder and mechanical sensors. however, using the speed control sensors causes many problems and reduced the whole system reliability. nowadays, the attention and development of sensorless speed control methods have increased and much of the research is devoted to these methods. in the synrm, the rotor position and speed are estimated using measured stator voltages and currents. therefore, based on accuracy, dependence on parameter variations of synrm and required speed, various methods have been proposed for sensorless speed control of the synrm. this paper examines sensorless speed control methods to clarify which kind of these methods is more suitable for synrm.