Design of Line Start Linear Permanent Magnet Synchronous Motor for Electromagnetic Catapult

The replacement of the conventionally used steam catapults with electromagnetic system in the launch application is proved to be more energy efficient and safe to handle. Electromagnetic launch system (EMLS) comprises many subsystems, of which, a linear electric motor (LEM) is a critical one. Linear electric motor provides additional thrust to launch for the shortest runway. Linear induction motor (LIM) is well preferred in EMLS since last two decades. Linear permanent magnet synchronous motor (LPMSM) has been selected to study due to many advantages they offer inspite of few disadvantages. Line start LPMSM is a induction start and synchronous run type motor. It is proved to be more efficient over induction motor in line start applications. Design and analysis of line start linear permanent magnet synchronous motor (LSLPMSM) is the main objectives of this work. The finite element analysis (FEA) of both LIM and LSLPMSM machines is carried out using ANSYS Electronic desktop (MAXWELL 2D). The comparison of the operational and equivalent circuit parameters of the LSLPMSM and LIM designs are also presented in this paper.