Sensor-less control of linear induction motor considering its asymmetric parameters

When we achiev a good performance of the field-oriented vector control system, it is necessary to detect the speed and flux of the motor. Usually it is hard to implemment these sensors. Then the sensor-less contro-system techniques using the observer instead of the sensor are being applied. On the other hand, there are also a lot of applications of the linear induction motor into the transportation system because of its simple structure. In these applications, it is required to implement the speed or position sensors along the rail or track in order to obtain a good performance of the control. therefore, the sensor-less field-oriented control system which doesn't need any speed-sensor is suitable to control the linear induction motor in the transportation systems.