Origins and Remedies for Resonant Activities in Step Motor Systems

摘要

The Hybrid, Permanent-Magnet Step Motor has served well as an incremental positioning device for the last twenty years, and recent advancements in motor design and drive technology promise to extend the efficiency and usefulness of the device as it competes with brushless servos. Nonetheless, there remain the age old problems of resonant sensitivity and the ubiquitous ringing which often consumes more than half of the available torque and creates nuisance vibration in the load. These problems tend to be more pronounced in lightly loaded motors and often become completely unmanageable at higher speeds where the system may actually break into sustained oscillation. If resonance can be brought under control, the throughput for a given motor can sometimes be doubled. This paper treats the theoretical basis for resonance and its limiting effects along with a collection of techniques for gaining control including recently perfected methods for introducing robust damping as an integral, self-contained feature of the drive electronics. We begin with a concise review of basic motor operation and stepping regimens.