Model Reference Adaptive Controlled Application to the Vector Controlled Permanent Magnet Synchronous Motor Drive

Abstract

This paper presents the parameters of permanent magnet synchronous motor i.e. speed (r), stator resistance (RS), q-axis inductance (Lq), and torque (Ts) is to be estimated by using Model Reference adaptive System(MRAS). To improve the performance of speed sensor less permanent magnet synchronous motor drives, especially at low speeds by identifying stator resistance together with speed. Several speed estimation methods for sensor less PMSM drives have been proposed but the Performance is not satisfactory at low speed. Model-based speed and stator resistance estimators are the most common schemes used in the literature. The stator resistance varies with the temperature of the machine, so it should be estimated adaptively. The proposed technique is completely Independent of stator resistance (Rs) and is less parameter sensitive, as the estimation-algorithm is only dependent on q-axis stator inductance (Lq). Also, the method requires less computational effort as the simplified expressions are used in the MRAS. In this proposed scheme sensor less technique is used, the aim at eliminating mechanical sensor, which are rather expensive and delicate, especially if accurate mounting and calibration are necessary, and at obtaining rotor position and angular velocity from the measurement of only electrical quantities. But the precision of position estimation often depends on motor’s parameters. To control PMSM position and speed sensors are indispensable. So the vector control technique is used for the control the PMSM position and speed sensor. MATLAB/ simulink based simulation is discussed.