分数阶阻尼裂纹转子的小波尺度谱分析方法研究

结合在分数阶微积分的基础上建立的裂纹转子系统模型和小波尺度谱，提出基于小波尺度谱的分数阶阻尼的转子裂纹故障诊断方法，并讨论了不同的裂纹深度下分数阶阻尼的裂纹转子系统的小波尺度谱和重分配尺度谱特性。仿真结果表明，分数阶阶次的改变对系统运动特性有很大的影响，在建立动力学模型时可以灵活调节分数阶阶次来改变转子系统的振动特性以达到诊断转子裂纹的最佳效果。提出的方法对裂纹故障敏感，能有效地提取裂纹转子系统中的故障信息。最后用实验进行了验证，实验结果与理论数值分析的结果相吻合，验证了文中建立的分数阶阻尼的裂纹转子系统模型的正确性。

Using Wavelet Scalogram Method to Analyze Cracked Rotor System with Fractional Order Damping

A fault diagnosis method of cracked rotor system with fractional order damping based on wavelet scalogram is proposed through the model of cracked rotor system based on the fractional calculus and wavelet scalogram. The characteristics of wavelet scalogram and reassigned scalogram from different crack depth in rotor system with fractional order damping are discussed. The simulation results show that the derivative order of damping and the crack depth have great influence to the dynamics characteristics of rotor system. The optimal derivative order of damping can be determined by adjusting the fractional order. The proposed method is sensitive to crack fault, which can effectively extract the crack fault information in the rotor system. Finally, the effectiveness of the proposed method is verified through the experiment rig. The experimental results are very consistent with the simulation results, and the proposed model of cracked rotor system based on the fractional calculus is correct.