Air gap control of multi-phase transverse flux permanent magnet linear synchronous motor by using independent vector control

This paper presents an air gap control method of a multi-phase transverse flux permanent magnet linear synchronous motor (MP-TFPMLSM) based on independent vector control. Especially, the MP-TFPMLSM is composed of symmetrical multi-phase and multiple-module structures, which are basically three-phase configurations. Hence, in this paper, a d-axis current control applying the d-q transformation and the independent vector control are proposed for the air gap control between two symmetric stators and mover of the MP-TFPMLSM. The control performance and characteristics of the MP-TFPMLSM, which is based on two basic three-phase structures of the air gap control and the position control of multi-phase linear machines using a concept of vector control are analyzed. As a result, the air gap control by using the independent vector control is a suitable method to efficiently control the interaction between stator and mover of the MP-TFPMLSM. The proposed method is easily implemented and has less computation time to design controllers for operating the multi-phase machines. The effectiveness of the proposed independent vector control algorithm is verified through several experimental results.