Development and Testing of a Four Pole Magnetic Bearing

A 4 pole radial active magnetic bearing actuator has been developed, constructed, and tested. Among the anticipated characteristics of this configuration were: higher specific load capacity, lower power losses, and improved stability as compared to otheT heteropolar configurations. The theoretical basis of each of these aspects will be investigated, and some limitations of the design will be discussed. Testing of the new actuator verified that higher load capacities are achievable. Stability problems with the prototype, due to interaction with the power amplifiers, limited the ability of the testing to investigate actuator stability improvements.