A Novel Switching Method for Shortening Block Feeding Portions in Short Secondary Member Linear Motors

In this paper, we propose a novel switching method for shortening block feeding portions in short secondary member linear motors. The proposed method involves shifts at every coil, which makes the length of feeding portions much shorter than that in the ordinary method with the shifts at every block section. Resulting advantages for adopting the proposed method are summarized as follows: 1) Concerning power supply: Owing to the extremely short feeding portions, improvement of power factor and efficiency becomes possible. And, since power is supplied to each coil for a very short time, the rating becomes a short-time one. 2) Concerning electric transient phenomena: By short-circuiting coils at both ends of the feeding portion during shifts, continuous power supply and smooth shifts become possible, reducing electric transient phenomena. The study is carried out through experiments as well as simulationsu singa hybrid method of the magnetic-fieldsa nd the electric-circuits analysis.