Analysis of Quasi-Zero Power Characteristic for a Permanent Magnetic Levitation System with a Variable Flux Path Control Mechanism

Abstract

This article focuses on the analysis of the quasi-zero power characteristic for a permanent magnetic levitation system with a variable flux path control mechanism. The system mainly consists of a disk permanent magnet, a pair of yokes, and a rotary actuator. The permanent magnet magnetized diametrically is rotated by the actuator, which can achieve the control of the levitation force by changing the flux. Unlike the electromagnetic system, the input to the actuator is used to maintain the rotation angle corresponding to the equilibrium position, not to directly produce a magnetic force. Therefore, the proposed system possesses a lower power consumption. Analysis of mechanism, current model, and different levitation control strategies are presented in this article. With the variable air gap length control and the constant air gap length control, the permanent magnetic levitation system performs well in levitation with quasi-zero power in loading experiments. The constant air gap control is demonstrated to possess higher safety when the levitation mass is changed, which has the potential for magnetic levitation transportation.