Redundant performance of multi-primary coupling linear induction motor

In order to improve the redundancy performance, a linear induction motor (LIM) can be designed to have m primaries (m is an integer and m≥2) sharing just one secondary. When anyone of the primaries runs in failure model, other remanent primaries could accomplish the scheduled target. This paper makes a study of the redundant performance of four-primary coupling LIM, the study refers to determination of equivalent circuit and the parameters based on the model of traditional induction motors, presentation of the model and the parameters in normal working conditions and different primary failure working conditions, and the calculation of the overloading current in terms of modeling and parameters of different fault modes. The result indicates that when 1# or 4# primary fails, the current amplitude increases to 1.166 times to maintain the thrust, when 2# or 3# primary fails, to 1.264 times.