A Three-Dimensional Measurement System for High-Temperature Superconducting Magnetic Bearings

For stable and safe operation of high-temperature superconducting flywheel energy storage system, adequate levitation force and stiffness of the high-temperature superconducting magnetic bearing (SMB) are necessary. In order to validate the design and research the levitation characteristics further, a three-dimensional measurement system for high-temperature SMB is developed in our laboratory. The measurement system consists of experiment system, motor drivers, data acquisition and processing, automatic control, and auxiliary devices. The measurement system has the following characteristics: high measurement precision and sensitivity, measurement suitable for both axial-type and radial-type SMB with different diameter and height, measurement of the axial and radial levitation forces, stiffness, and time relaxation, and measurement of force with precise displacement in three-dimensional space. The maximal axial and radial levitation forces that the measurement system can measure are 3000 and 2000 N with the precision of 1.5 parts per thousand. The measurement precision is calibrated and the test results for high-temperature SMB are presented.