End effect in linear induction and rotating electrical machines

The finite length of the iron core (stator) has a significant impact on the performance of linear induction machines (LIMs). The performance of a cylindrical symmetric linear induction machine (CSLIM) has been studied considering the impact of the finite stator length. The analytical procedure, originally developed for calculation of plane linear induction machines, has been modified to facilitate the analysis of CSLIM. The procedure is based on Fourier series expansions of the electromagnetic quantities and the air-gap length. This study further provides information on the effect of finite length of tooth in the direction of rotation in rotating electrical machines. As examples, the overheating of the stator core in a 500 MVA synchronous hydrogenerator and the detrimental impact of the end effect on a 506.5 MVA synchronous turbogenerator in a nuclear power station is described.