Speed Control of Permanent Magnet Synchronous Motors by Adaptive Auto-Tuning

Abstract

An adaptive auto-tuning algorithm for a digital signal processor based permanent magnet synchronous motor drive is proposed in this article. The auto-tuning scheme includes two steps. First, an adaptive load observer is employed to estimate the load inertia. Second, in order to be compatible with conventional drives, we use adaptive two-degree-of-freedom proportional-plus-integral tuning, whose initial gains are individually designed by a Bode diagram and an extension of the frequency-zone method to decouple the tuning gains in a multi-loop control system. Finally, the experimental results of estimating some known load inertias and square-wave speed responses have verified the effectiveness of the proposed auto-tuning algorithm.

Keywords:

• adaptive auto-tuning
• adaptive load observer
• two-degree-of-freedom proportional-plus-integral tuning

Acknowledgment

The authors would like to express their appreciation to NSC for support under contract NSC 93-2622-E-218-018-CC3.