Automated Parameter Identification Platform for Magnetic Levitation Systems: Case Bearingless Machine

This paper presents automated platform that can be used to identify parameters of magnetic levitated systems. Identification platform itself consists of 3-axis force measurement sensors and 2-axis stepper motors driven linear ball screw tracks. This kind of construction enables to measure the force produced by electromagnets in any angle and in any position in the air gap. Measurement system is controllable so the identification process can be automated. As a case study, self and mutual inductances of an interior permanent magnet bearingless machine are identified for the motor control purposes. Force sensors are used to measure the unbalance magnetic pull inflicted by the permanent magnets embedded in the rotor. Automated measuring procedure is used to determine self and mutual inductances of the bearingless motor. System functionality is validated by comparing the measured magnetic pull results to FEM analysis and inductance measurement to different prediction method based on standard motor drive identification process. Based on achieved results presented automated platform can be used to identify parameters of magnetically levitated system.