The design of small high speed brushless DC drives with precise speed stability

Consideration is given to the design of small brushless DC drives for applications such as laser scanners or gyros in which high speeds are coupled with the requirement for precise speed stability. The design features of these drives are discussed with attention being given to minimization of torque ripple and the control strategies necessary to limit speed oscillations, inherent in this type of drive, to give speed stability to better than five parts per million. Experimental results for speed stability for a commercially available drive are presented and a prototype drive for the application is described.<>