Comparison of linear switched reluctance machines for vertical propulsion application: Analysis, design, and experimental correlation

This paper presents the comparison of four linear switched reluctance machines (LSRMs) as possible candidates for application in vertical elevators. Linear induction and linear synchronous machines have been presented and experimentally tested in vertical elevators. In this paper, four longitudinal LSRM configurations are presented and designed to operate as propulsion actuators in a vertical elevator prototype. Two of the four configurations have been presented earlier in horizontal propulsion experiments, and a third one has been proposed for application in vertical elevators. All four LSRMs are designed for similar static force profiles to allow for their comparison. The designed LSRM configurations are compared by using finite-element analysis and dynamic control simulations. The stator, translator; and copper winding weight and dimensions, footprint area, active material weight, normal forces and payload capabilities for all four configurations are contrasted. The configuration with the highest payload capability is chosen for implementation in an experimental prototype. The prototype vertical elevator is 1.27 m tall with a 1-ft-tall elevator vehicle with no counterweights and uses two LSRM setups on each side. The experimental correlation of propulsion force and inductance is presented to validate the theoretical design method used in this research.