Analysis on the Operating Stability of a Magnetic Bearing

In this paper, the production mechanism of self-excited vibration of a magnetic bearing-rotor system is explained theoretically, and the related operating stability is investigated. A clan of the stable boundary curve derived theoretically is basically in agreement with the experiments. Tqose provide a foundation to choose the parameters of a rotor system, such as the parameters of rotor, damper and magnetic bearing. In this paper, a prototype device could be run up to a high speed(30,000r.p.m.) stably and repeat~dly.This device possesses a rotor which weighs 10 kilogram and is suspended with a controlled magnetic bearing.