Principle and Control of Radial AC Hybrid Magnetic Bearing

In the paper, the configuration and principle of the radial AC hybrid magnetic bearings are expounded, and the mathematical models of suspension forces are deduced by using the method of equivalent magnetic circuits. Nonlinearities of suspension forces and cross coupling between the two degrees of freedom are studied further by calculating the suspension forces at different displacements and control currents to validate the feasibility of the mathematical models. Then based on the mathematics models , the digital control system is designed. The hardware based on TMS320F2812 is developed, and the software of control system is developed. The experiments are completed and the test results have shown that the AC hybrid magnetic bearing has good dynamic and static performance.