A Method for Improving Speed Control Characteristics at Very Low Speed Region by The Least Order Disturbance Observer

Abstract

In the speed control system of motors using the low resolution rotary encoder, the period of the encoder pulses becomes longer than that of the speed control at the very low speed region. It gets impossible to obtain the accurate speed information in the period of the speed control.
So we suggest an easy speed estimating method at the very low speed region using the least order disturbance observer that has been used widely. And we investigate an estimating method of the motor inertia that especially affects the speed estimation.
This paper shows these principle of the method, the simulation result and the experimental one. It makes it clear that the characteristics of the speed control at the very low speed region is improved by using the least order disturbance observer.