Dual-Stator Versus Dual-Mover Segmented Secondary Hybrid Excited Linear Flux Switching Machine for Ropeless Elevator System

Rotatory electric motors provide low efficiency in the case of linear motion. The reason for this is the mechanical conversion system required to convert rotary torque to linear thrust force. In this paper, two novel linear machines i.e., a Dual-Mover Segmented Secondary Hybrid Excited Linear Flux Switching Machine (DMSSHELFSM) and Dual-Stator Segmented Secondary Hybrid Excited Linear Flux Switching Machine (DSSSHELFSM), were investigated and compared for a ropeless vertical elevator system. The novelties of these designs include both series and parallel magnetic circuits, a complementary AC coil structure, and their unequal primary tooth width. Results reveal that the DSSSHELFSM exhibits better performance with higher and more sinusoidal flux linkage, higher thrust force, and a robust mechanical structure. Secondly, the selected linear motor was optimized using a deterministic optimization approach. An average thrust force of 10kN and a thrust force ripple ratio of less than 10% were considered as performance constraints during the optimization process. Finally, full-scale no-load experimental results were obtained, and they validated the research.