IEEE Transactions on Energy Conversion, Vol.30, No.3, 1218-1227, 2015
A Study of Unbalanced Magnetic Pull in Brushless Doubly Fed Machines
This paper studies the unbalanced magnetic pull in the brushless doubly fed machine (BDFM) caused by both static and dynamic rotor eccentricities. Several parallel winding designs for the two stator windings are proposed, and the practicality of such designs is discussedwith respect to direct coupling between the stator windings and with rotor undesirable harmonic fields. Once practical parallel winding designs are established, their effects on reducing deflection as a result of static and dynamic eccentricities are shown and compared with series wound stator. This study has been carried out on a prototype D400 250-kW BDFM.
Keywords:Brushless doubly fed machine (BDFM);finite-element (FE) analysis;parallel winding;rotor eccentricity;unbalanced magnetic pull (UMP)