automation4me - Drive Tech

The adaptive observer for estimating magnetic flux and speed, which is used to realize high-performance drive with induction motors, will be described in this article.

With adaptive observers, it is desirable in terms of economy to omit the voltage sensor and to replace the stator input voltage, which is needed as input for the reference value and the actual value, some form of correction will be necessary since the estimation accuracy will be affected.	Click to zoom
In our current development, we added a disturbance compensating function to a conventional adaptive observer and in that way attempted the compensation of voltage error. We have been able to confirm by simulation that the use of this method enables the reduction of the influence of offset errors and peak value errors between the reference value and the actual value on the estimates.	Downloadable pdf