Harmonic due to slots in electric machines

SLOTS HAVE BEEN a known source of harmonics in electric machines for many years. Almost as long as engineers have been designing synchronous generators, they have attempted to suppress slot harmonics in the output waveform. Because of the complex nature of this problem most of the previous work in this field has been of an empirical or semiempirical nature. Recent developments in the digital computer field have made a direct frontal assault on this long standing problem feasible. Further, use of the digital computer makes it possible to determine the optimum machine from a fairly large number of proposed designs. The approach to this problem developed in this article is particularly designed for solution of the problem by digital techniques which can be handled by most punched-card digital computers.