Three-Dimensional Target Space Magnetic Leakage Shielding for Automated Guided Vehicle Inductive Charging System
Pan Shuaishuai1, Mai Ruikun1,2, Xu Yefei1, Xie Zhaojie1, Wang Zhulin1
1. School of Electrical Engineering Southwest Jiaotong University Chengdu 611756 China; 2. National Rail Transit Electrification and Automation Engineering Technique Research Center Chengdu 611756 China
Abstract：Magnetic leakage of the automated guided vehicle (AGV) inductive charging system endangers the organism’s health and interferes with the regular operation of sensitive electromagnetic equipment. An optimization method of reactive resonant coil equivalent reactance is proposed to reduce the maximum magnetic induction intensity in the three-dimensional target space. The proposed method divides the target space into many target points evenly. The optimal equivalent reactance can be obtained by traversing the equivalent reactance of the reactive resonant coil to minimize the maximum magnetic induction intensity of the target point. First, the expression of system current, which contains the equivalent reactance of the reactive resonant coil is derived. The influence of system current on magnetic induction intensity at any point is analyzed. The relationship between the equivalent reactance of the reactive resonant coil and the magnetic shielding effect at that point is obtained. Then, the magnetic shielding target is extended from a single point to the target space. The optimal equivalent reactance of the reactive resonant coil is derived by the proposed optimization method. Finally, the experimental results demonstrate that the magnetic induction intensity of the target space meets the safety standards when the reactive resonant coil obtains the optimal equivalent reactance. The maximum magnetic induction intensity in the target space was reduced by 53.40%, and the average decreased by 58.15% compared with that without the reactive resonant coil. The system efficiency was reduced by only 0.31%.
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2022, Vol. 37 
