Direct Torque Control of ALA Synchronous Reluctance Machine Based on Modified Integrator

The axially laminated anisotropic (ALA) rotor motor is a competitive candidate for high performance variable speed drives. However, in the vector control applications, in order to keep the synchronism between the rotor and the flux, a sensor is always required to detect the position of the rotor. But the utilization of sensor will increase the cost and deteriorate the stability, or even be forbidden in some applications. In this paper, the direct torque control (DTC) scheme is employed to control the ALA synchronous reluctance machines (SRM). A modified integrator is developed to solve problems associated with pure integrator and produced due to the structural differences between ALA-SRM and induction motor. The performance of this integrator is studied and verified through simulation and experiment. Finally, the experimental investigation on a DSP-based drive system is presented. It´s validated that the motor with the proposed control strategy has satisfactory starting and operating performance.