Comparison of trapezoidal and sinusoidal pwm techniques for speed and position control of pmsm

Abstract

In this article, speed and position controls of Permanent Magnet Synchronous Motor (PMSM) are performed by using a genetic algorithm-based con-troller. Hall Effect sensors have been used to obtain position data of the motor. Since Hall Effect sensors have been mounted, PMSM has been driven as a Brushless DC (BLDC) motor. Sinusoidal and trapezoidal current reference models have been used in the control sys-tem. The proposed control system has been operated for speed control as well as position control of the motor. The developed genetic-based speed and position control method has been tested for both trapezoidal and sinusoidal PWM commutation techniques. The results obtained from these commutation techniques have been compared. Speed and position results of the motor have been obtained under the different load and operating conditions. The results reveal that the proposed control system is reliable, robust and effective. for many industrial variable speed applications that re-quire speed and position control [1] and [2]. However, the performances of the PMSMs are very sensitive to parameter and load variations. To overcome these problems, several modern control strategies, such as PI (Proportional-Integral) or PID (Proportional-Integral-Derivative) control, Fuzzy Logic Control, Neural Network and Genetic Algorithm Control methods are proposed for speed control [3]. In PMSMs, it is crucial to determine the rotor position and to perform commutation exactly at the ac-curate time. Hall Effect sensors and encoders are used to receive the information of position and speed through the rotor. Position and speed data can be received without using sensors; nevertheless, the mi-croprocessor must have both high memory capacity and rapid process time.