Title :
Calculation of Radial Forces in Cage Induction Motors at Start—The Effect of Rotor Differential
Author :
Dorrell, David G. ; Hsieh, Min-Fu
Author_Institution :
Sch. of Electr., Mech. & Mechatron. Syst., Univ. of Technol. Sydney, Sydney, NSW, Australia
Abstract :
In this paper, the radial forces in an induction motor are calculated using finite element analysis. These radial forces (or unbalanced magnetic pull-UMP) are generated when the rotor is eccentric. The work illustrates the importance of higher winding harmonics and rotor differential leakage in the starting UMP. Examples of a 6 pole machine with 26 and 40 bar rotors show that increasing the bar number and air-gap length will reduce the UMP. Further studies are carried out using parameter variation and a 10-pole machine is also addressed, where experimental results exist, in order to validate the calculation.
Keywords :
finite element analysis; induction motors; machine theory; rotors; 10-pole machine; 6 pole machine; UMP; air-gap length; bar number; bar rotors; cage induction motors; finite element analysis; parameter variation; radial forces calculation; rotor differential leakage; unbalanced magnetic pull; winding harmonics; Air gaps; Bars; Finite element methods; Induction motors; Magnetic analysis; Magnetic flux; Mechatronics; Rotors; Stators; Stress; Induction motors; unbalanced magnetic pull;
Journal_Title :
Magnetics, IEEE Transactions on
DOI :
10.1109/TMAG.2010.2044389
