Simulation analysis and experimental study of the diamagnetically levitated electrostatic micromotor

摘要

The diamagnetically levitated electrostatic micromotor (DLEM), in which five degree of freedom of the levitated pyrolytic graphite rotor are stabilized by permanent magnets except its rotational degree of freedom around the main axis, was studied. The DLEMs were fabricated by using Micro-Electro-Mechanical Systems (MEMS) process and precision machining. The levitation properties of DLEM, which have been analyzed by the finite-element method (FEM) software Ansoft Maxwell 3D, were proved by the levitation experiments. Based on our designed measurement and control system, we successfully realized the continuous operation of the axial variable-capacitance motor by open-loop and closed-loop control. For DLEM1 device, under the fixed frequency and variable frequency open-loop logic with driving voltage of 43 V in air, the achieved rotational speed is 15.4 r/ min and 70.0 r/min, respectively. For DLEM2 device, under the variable frequency open-loop and closed-loop control with driving voltage of 30 V in air, the achieved rotational speed is 46.9 r/min and 26.8 r/min, respectively. Experimental results show that the motor presents high reliability under the closed-loop rotational control.