电磁推力机构的一种分析方法

基于平行排列的同轴双圆形线圈模型,导出了计算电磁推力的基本分析公式。计算指出:两个单匝线圈的互感、互感对位移的导数在其半径相等时取得极大值。针对一具体算例,通过改变感应线圈的半径,计算了通电线圈的电流、感应线圈的涡流和电磁推力的变化情况。分析结果表明,在线圈电流衰减到零之前,电磁推力会变为电磁吸力,从而引起开关触头合分时的反弹现象。最后给出一种新的电磁推力机构动态分析的方法,藉此可以方便地实现电磁推力机构的综合优化设计。

An Analytical Method for Electromagnetic Repulsion Mechanism

Based on the coaxially paralleled dual-coils model, a fundamental analytical formula was deduced for electromagnetic repulsion force calculation. Theoretical computation indicated that the mutual inductance and its derivative vs. displacement between the two single turn coils reached their maximum value when the coils?radii were the same. Regarding an example, the current in the energizing coil and the eddy current in the induction coil, as well as their electromagnetic repulsion force, were calculated by varying the radius of the induction coil. The analyzed results demonstrated that, the electromagnetic repulsion force could be turned into suction force before the energizing current decreased to zero, therefore resulting in bouncing phenomenon of the switching contacts during opening or closing operation. Finally, a new dynamic simulating method for electromagnetic repulsion mechanism was deduced,based on which comprehensive optimization design of the repulsion mechanism can be achieved.