Application of Active Magnetic Bearing for Tubular Linear Induction Motor in Oil Pumping

An active magnetic bearing (AMB) to support the shaft of a tubular linear induction motor (TLIM) applied to oil pumping is proposed. Instead of the usual eight-pole AMB, a different concept is adopted where a DC-excited primitive bearingless machine is used as a magnetic bearing. The AMB is a 3-phase one for which a lower number of wires connections and power devices are among its advantages. This paper focuses on the design of the AMB system. A finite element analysis of the flux density and of the relationship between the radial force and the suspension winding current are explored. The magnetic system is modeled and simulation is performed to tune the controller parameters.