A study of rotor eccentricities effects on brushless doubly fed machines performance

This paper studies the unbalanced magnetic pull (UMP) in the Brushless Doubly-Fed Machine (BDFM). Analytical study is performed to derive the UMP, then, Finite element (FE) analysis, which has been verified experimentally, is used to verify the analytical method. The BDFM with different types of rotor eccentricities including static and dynamic eccentricities, are also modeled in FE method and their resultant UMPs are obtained. The results are compared with the case at which a perfectly constructed rotor is considered. The study has been carried out on a prototype D400 250 kW BDFM