Series-Winding Topology Converter for Active Magnetic Bearing Drive

Active magnetic bearing is a key technology of high-speed rotational machine. As the power amplifier, the performance of power electronics converter is critical to the active magnetic bearing system. This article introduces the topology development progress of active magnetic bearing drive and describes a novel converter with series-winding topology. Compared with the traditional topology, the series-winding topology needs less switches, makes fully use of devices, and reduces the volume and cost of the controller. Compared with the conventional active magnetic bearing drive topology, the series-winding topology provides higher voltage utilization, ensuring better current control capability. The basic properties and control strategies of the series-winding topology are analyzed. The topology can also be expanded to a N-windings system. Experimental work verify the availability of the topology. On test rig, the magnetic bearing has been levitated with position error about 10% of the airgap length in the rotation speed up to 5400 r/min.