Abstract: Based on summarizing and comparing the methods of calculating the disturb torque acted on electrostatically supported rotor, a proper method, that is calculating the torque caused by electrostatic force relative to rotor’s mass center, is employed to get the torque in device with 6-electrodes onstruction which forms a half-bowl shape. The torque is described in terms of the rotor’s eccentricity relative to the electrodes case, rotor’s non-sphericity, the deviation angle of rotor’s spin axis relative to shell coordinate voltage on electrodes and empty electrodes which is not occupied by electrodes over the entire electrodes case’s surface . Simulation results confirm the range of those parameters by which the disturb torque will be smaller than a certain value. The outcome is helpful to design the balance device for spherical rotor.

Key words: bowl support Disturbing torque Equilibrium