An improved method to control the speed and flux of PM-BLDC motors

Permanent Magnet Brushless DC (PM-BLDC) motors have become quite widespread and are utilized to serve for a variety of industrial purposes, because of their simple structure, high reliability and ease of control. Space Vectors theory is one of the most widely used methods which is implemented for controlling PM-BLDC. Supposing that each space vector refers to a unique arrangement of switch states, this theory calculates speed (or torque) error and stator flux error, compared to reference parameters. Consecutively, based on the aforementioned issues the most appropriate voltage vectors are attained to excite the stator phases. Ripples in speed and torque, are the main concerns, such methods try to deal with. In this paper, in addition to speed and flux errors, the speed variation slope is used as an auxiliary control parameter for a more precise speed control and decreasing speed ripples. The simulation results demonstrate a promising efficacy and accuracy of the proposed method.