Abstract:The working principle for active magnetic suspension bearing (AMB) systems was introduced. Its mechanical and electrical equations were established. The electromagnetic parameters design of electromagnet was analyzed in theory, and calculated according to a practical example, for a kind of magnetic suspension bearing system based on the E type structure electromagnet. Moreover, 2D electromagnetic field analysis by ANSYS software for the E-type electromagnet was done to verify. On this basis, the structural form of numerical control system for a magnetic suspension bearing system was illustrated, according to developed a four-degree (4D) of freedom magnetic suspension bearing prototype, and test of example suspension was completed. Experiments validate the theoretic design of this prototype is correct, which provides reference for further design of the magnetic suspension bearing.