工业磁轴承电涡流阻尼伴随特性研究

Damper co-located characteristics of industrial magnetic bearing

针对工业磁轴承中电涡流阻尼效应暂态认知难的问题,通过分析电涡流阻尼的伴随特性定量评价了其在磁轴承控制过程中的作用。首先引入磁矢位对电磁感应定律中的线积分和面积分不同表述形式的电涡流进行了统一,进而推导了工业磁轴承在PWM控制下的工作由电流的交变特性引起电生阻尼和机械振动引起的动生阻尼简化数学模型;然后通过Matlab-Simulink对单自由度磁轴承仿真分析,并且与同控制条件下未考虑涡流效应的模型进行了对比;最后通过冲击响应仿真实验验证了伴随效应,定量评价抑制振动和工作电流特性。研究结果表明,暂态过程中动生阻尼和电生阻尼对工业磁轴承存在着自稳效应,加快了控制电流稳态响应;另外计入电涡流阻尼效应的转子振动位移峰值相对未计入的降低了10.23%。

Aiming at transient electrical eddy current damping effect of industrial magnetic bearing hard to describe,features of eddy current damper was analysied by us and its effect was quantitatively evaluated. Firstly,a sample model of industrial PWM magnetic bearing with electric damper and motional damper was derived; then,a SDOF magnetic bearing was simulated,contrastive analysised the vibrational characteristics by Matlab-Simulink; finally,co-located characteristics,quantitative evaluation of vibration suppression and feature of current was verified by simulation of impact response. The results indicate,because of motional damper and electrical damper in industrial magnetic bearing,self-stabilzition existed during transient process,control current was stabilized faster,and the peak value of vibratory displacement decrease 10. 23% comparing with the general case.