Optimized Design of New Coupling Mechanism for Electric Vehicles
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摘要: 针对电动汽车无线充电应用,提出了一种凹凸型磁耦合机构,在减小磁芯体积的情况下实现了更好的耦合特性,提高了系统功率传输能力. 基于有限元理论,利用COMSOL电磁场仿真软件,建立了凹凸型耦合机构的有限元仿真模型,针对线圈两端凸起磁芯高度、线圈两端凸起磁芯长度配比、磁芯长度、磁芯长度与宽度之间的约束关系以及磁芯厚度等主要结构参数从互感及耦合系数等角度分别进行了分析和优化设计,并讨论了磁芯变薄后的磁饱和特性. 通过仿真和实验测试结果验证了所设计耦合机构的可行性及在磁场分布及耦合特性方面的优势,使得系统的输出功率和效率相对原条状磁芯结构分别提高了37%和10%.Abstract: Aimed at the application of wireless charging in electric vehicles, a type of concave-convex magnetic coupling mechanism is proposed, which realizes better coupling characteristics and improves the system power transmission capacity. Based on the finite element theory and the COMSOL simulation software, a model of the concave-convex coupling mechanism was developed. According to the height of the convex magnetic core at both ends of the coil, the length ratio of the convex magnetic core at both ends of the coil, and the core length, the relationship between the length and the width of the core and the main structural parameters such as the thickness of the core was analysed and optimised from the perspective of mutual inductance and coupling coefficient, respectively. The magnetic saturation after thinning is also discussed. The feasibility of the coupled mechanism and the advantages of the magnetic field distribution and coupling characteristics were verified by the simulation and experimental results. The output power and efficiency of the system improved by 37% and 10%, respectively, compared with those of the original strip core structure.
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Key words:
- electric vehicle /
- static charging /
- concavity and convexity /
- coupling
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表 1 电磁耦合机构磁芯参数
Table 1. Electromagnetic coupling mechanism core parmeters
参数 原结构 新结构 参数 原结构 新结构 x/mm 279 270 f/kHz 20 20 y/mm 28 36 M/μH 96.10 115.95 z/mm 16 9 k 0.173 0.188 Vc/cm3 1 500 1 166 Rp/Ω 0.270 0.267 Ip/A 23 23 Rs/Ω 0.270 0.263 注:Vc为磁芯用量总体积;f为系统工作频率;Rp、Rs分别为原、副边线圈的阻值. -
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