Implementation of maximum torque per amperage control using estimation technique of rotor time constant

The spindle motor in machine tool mostly adopt induction motor. In order to achieve dynamic control of the magnetic field and torque, one needs to estimate the synchronous induction motor electrical angle. The calculation is based on the basis of the rotor time constant. The accuracy of the parameter measurements will affect the performance significantly. How to improve the spindle motor torque is also an important object in development indirect control of induction motor. Through the maximum torque per amperage control (MTPA) method, one can effectively maximize the torque. In general, the field current and torque current will be set to the same values. But the simulation is found that when there are severe magnetic saturation phenomenon, torque will be less than expected. Therefore, we will use the exciting flux method to achieve maximum torque. This study performs the rotor time constant identification and exciting flux control method by Simulink simulation.