Relation between Minimal Speed and Rotational Inertia of Stable PM Maglev Bearing Rotator
The authors’ former works demonstrated that a passive magnetic (PM) rotator supported merely by PM bearings has a minimal speed, above which it can stabilize its equilibrium, under the function of a so-called Gyro-effect. It is unclear, however, by which factors is this minimal speed determined. To investigate the effect of rotor inertia on minimal speed, three same rotors made of different materials were manufactured: rotor A was made of plastic and its rotary inertia is 6.293×10-5 (kg·m2); rotor B was made of aluminum and its inertia is 1.074×10-4 (kg·m2); rotor C was made of steel and its inertia is 2.081×10-4 (kg·m2).The rotors were tested in a model with PM bearings and the maximal eccentric distance of the rotors was measured. In case the maximal eccentric distance of the rotor was smaller than the gap between the rotor and the stator, the rotor could be considered being suspended. In such way the minimal speed for stable levitation of the rotor A, B and C was obtained to be 4597, 3030 and 2222 rpm respectively. It concluded that the minimal speed increases with the square of decreasing inertia according to a formula: y=1/(a+bx+cx2), here y: minimal speed, with unit rad/s; x: rotational inertia, with unit kg·m2; a, b, c are constants: a=3.5367×10-5，b=39.1012，c=－8.8726×104.
PM Bearing Rotational Inertia Minimal Stable Speed Eccentric Distance
Qian Kunxi Xu Zihao Wang Hao
Jiangsu University, Zhenjiang, 212013, China
国际会议
The Twelfth International Symposium on Magnetic Bearings(第十二届国际磁悬浮轴承学术会议)
武汉
英文
429-434
2010-08-22（万方平台首次上网日期，不代表论文的发表时间）