Motor Optimal Efficiency Direct Torque / Force Control

With the continuous study of AC drives , the technology has been improved greatly, which has already taken the place of DC drives gradually and is applied to numerous fields. Today, AC drives are developed in the way to digital, intelligent, integrated system. Since DTC has been developed for nearly 20 years as a AC drive technology, it has become the most popular technology in the field of AC drive for its advantages of direct control, short adjusting time and unsensitive with the motor parameters.A transient mathematical model of the asynchronous motor is built taking core loss into account to improve the torque performance . A method is proposed to minimize the total loss according to the relation between the efficiency and the rotor flux . A DTC system using this method appear high efficiency in matlab-simulation.The same idea is used to the line induction motor . A method is proposed to minimize the loss by finding the relation between the efficiency and the stator flux . Through simulation , we can find that this method give a higher efficiency.Also some work is done to the hardware.