Design Criterion for Dual-Modular Permanent Magnet Linear Synchronous Motor With Long Stroke and High Flexibility

Permanent magnet linear synchronous motor (PMLSM) has a wide application prospect in transmission systems of automatic production, logistics, and other fields. However, the existing PMLSM has the problems of poor flexibility and large thrust fluctuation adapted to load and stroke variation. In order to solve this problem, a dual-modular PMLSM is proposed. The motor can be flexibly configured with multiple-unit-primary and multiple-unit-secondary, and achieve low thrust fluctuation. The matching criterion of unit-primary (UP) and secondary is established to reveal the relationship between the slot/pole combination and the winding utilization. The rules of the average thrust varying with the different UP and unit-secondary (US) lengths are illustrated. Then, the matching criterion of different UP is proposed, and the optimization method of the spacing between UP (
S
₁
) is obtained by establishing the end force model. The design standard of the optimal
S
₁
is obtained by combining the two factors of minimum detent force and maximum thrust. The results are verified by the simulation and experiments on a 3UP-96US dual-modular PMLSM circular transmission line system and its prototype.