Measurement and Calculation of Unbalanced Magnetic Pull in Wound Rotor Induction Machine.

This paper addresses the measurement and calculation of unbalanced magnetic pull (UMP) in a wound rotor induction machine. A new rig for measuring UMP is presented. To our knowledge, this type of rig has not been tested before. This paper details the force calculation method and a method for splitting the UMP and torque. Wound rotor induction machines are now popular as generators in wind turbines. It is important to maintain good operation and low bearing wear, and the UMP in these machines is higher than that of the cage-rotor equivalent because the cage damps the UMP. There is little literature on the UMP in a wound rotor machine. [ABSTRACT FROM AUTHOR]