摘要
通过建立电磁力的时域模型,利用数值仿真方法,研究存在涡流效应的磁悬浮转子的非线性振动特性。结果表明:在主共振响应方面,整体涡流效应越强,转子频响曲线左偏程度越大,甚至出现"跳跃",转子在共振区的振幅也越大;涡流效应使转子振幅的频谱中产生超谐波和次谐波频率成分,增大谐波的响应幅值。
The time domain model is built for electromagnetic force,and the nonlinear vibration characteristics of magnetically suspended rotor considering effect of eddy currents are studied by using numerical simulation method. The results show that in the aspect of primary resonant response,the more powerful effect of eddy currents is,the greater the left deviation degree of rotor frequency response curve,even appearing"jump",the larger the amplitude of rotor in resonance region is. The frequency component of ultraharmonics and subharmonics are generated from frequency spectrum of vibration amplitude of rotor by effect of eddy currents,and the response amplitude of harmonics is increased.
引文
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