磁流變阻尼器的磁路分析

Magnetic circuit analysis of MR damper

蘇益弘(Yi-Hong Su)

指導教授 ： 韓麗龍

國立臺北科技大學/機電學院/製造科技研究所/碩士(2008年)

摘要

磁流變液是以軟磁微粒分散於不導磁的油中形成懸浮液，飽和磁通密度很高而且矯頑力很小。當外加磁場時，磁流變液在毫秒級的瞬間內由流動性良好的Newton流體變成Bingham流體，而這種變化是連續、迅速、可逆，容易控制。因此磁流變液阻尼器是一種理想的半主動控制裝置，因為當阻尼力在調節過程中發生故障，磁流變液阻尼器仍然能以被動式的方式使用。
本論文在探討磁流變液阻尼器間隙大小、磁場強度、磁通密度與偏心後間隙的改變對磁場特性之影響。將這些參數使用Magneto V64電磁場分析軟體，找出在相同電流與最佳間隙下，產生最大磁場，讓磁流變阻尼器有較好的效果。從理想化的間隙再比較偏心與偏角後對阻尼效應的影響的。最後再依照這些數據來估計是否需要考慮偏心導致左、右兩邊間隙不同，因而讓左、右兩邊磁場強度不同，而影響磁流變阻尼器的效應。

關鍵字

磁流變液 ； 磁通密度 ； 矯頑力 ； Newtonian流體 ； 阻尼器

並列摘要

Magneto-rheological (MR) fluid is a high saturation magnetic flux density and low coercive force suspension, which contains soft magnetic particles dispersed in the non-magnetic oil. When an external magnetic field is applied, the MR fluid changes from good flow of Newtonian fluid into Bingham plastic in few millisecond and this change is continuous, rapid, reversible, and easy to control. Therefore MR fluid damper is an ideal semi-active control device, because when the damping force in adjusting process could fault its performance, MR fluid damper still able to use passive mode.
This paper aims to study MR fluid damper gap, magnetic field intensity, magnetic flux density, and eccentricity that may affect the magnetic field characteristics. To obtain a good magneto-rheological damper, these parameters will be analyzed with Magneto V64 software and found the largest magnetic field under the same current and best gap. From the ideal gap, we will compare its efficiency of eccentric and inclined axis after impact.
Finally, in accordance with these data to estimate whether it is necessary to consider eccentric left and right sides of different space, so to the left and right sides of the magnetic field intensity, and impact of magnetic damper effect.

並列關鍵字

Magneto-rheological (MR) Fluids ； magnetic flux density ； coercive force ； Newtonian fluid ； damper

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