Improvement of Low Speed Characteristics in Induction Motor Drives by Reduced Order Torque Observer

감소차원 토크관측기를 이용한 유도전동기의 저속운전특성 개선

In the speed control system of motors using the low resolution rotary encoder, the period of encoder pulse becomes longer than the sampling time for speed control in the range of very low speed. Therefore, it is difficult to obtain accurate speed information. In this paper, the speed estimating method at the very low speed region using reduced order torque observer, which has been widely used, is examined. The results of simulation show that the characteristics of the speed control at the very low speed region is improved by using the reduced order torque observer.