Linear asynchronous motor for traction or material transport - has edge effect fields for centering secondary part under primary windings

摘要

The linear motor includes a primary part which comprises two core components, each one laminated, running in mutually perpendicular directions. The cores (2) at right angles to the direction of motion (D) span the width of the secondary assembly (7,8) and have at least four slots. The cores (3) parallel to the direction of motion span the spaces between successive cores of the first type, and comprise one more section than the number of slots in the transverse cores (2). A concentrated multiphase winding (4,5) is arranged around the core teeth. The phase across the direction of motion follow the normal sequence to the centre of the core and then the reverse sequence to the opposite edge. In the direction of motion (D) all coils in any one line follow the normal phase sequence. The excitation provided by this coil and core arrangement gives the required linear motion, centering for the secondary part, and magnetic levitation.