Measurement of permanent maglev turbine´s rotor eccentricity by Hall sensors

To investigate the suspension performance of passive magnetic bearings and measure the minimal speed for suspension, a permanent maglev turbine was designed. A measuring device for rotor eccentricity was assembled and the calculation model of the eccentricity was established. The device used four Hall sensors evenly fixed on the turbine stator to detect rotor´s position, and the rotor´s rotating speed was measured by speed sensor. The results showed that the rotor eccentricity would be less than the gap between the stator and rotor and maintain stable rotation when rotating speed exceeded 1800 rpm. This indicates that stable permanent magnetic levitation in all of six degrees of freedom can be achieved by gyro-effect.