考虑油膜不确定性的滑动轴承-转子系统不平衡量识别

Unbalance parameters identification for a sliding bearing-rotor system considering the uncertainty of parameters

针对滑动轴承-转子系统不平衡量识别过程中滑动轴承油膜特性系数的不确定性,提出了考虑油膜不确定性的转子系统不平衡量的识别方法。该方法考虑滑动轴承油膜特性系数为不确定因素,基于区间数学理论和一阶泰勒级数展开式的区间法将具有不确定性结构的不平衡量识别问题转化为两类确定性结构的不平衡量识别问题;对于确定性结构的不平衡量识别问题根据滑动轴承-转子系统运行时不平衡量是以不平衡力的形式作用于主轴上,提出将不平衡力在时域内用一系列的脉冲函数来表示,利用滑动轴承-转子系统的瞬态响应分析方法来构建正问题,结合正则化方法处理不平衡量识别中的病态问题,获得转子系统不平衡量的上边界和下边界。通过一转子实验台检验了不平衡量识别方法的有效性和鲁棒性。

An identification method considering the uncertainty of the dynamic parameters of bearings in a sliding bearing-rotor system was presented to identify the unbalance parameters of the system. In the method,the unbalance parameters identification was transformed into two deterministic inverse problems by using the interval analysis with the first order Taylor series expansion. Then,the unbalance forces,used as the unblance parameters,were expressed as a series of impulse functions in time domain and the discretized convolution integral of unbalance forces and the corresponding transient response functions of the sliding bearing-rotor system were adopted to construct a forward model. A regularization method was introduced to deal with the ill-posedness arising from the deconvolution and noisy responses,and then the upper and lower bounds of the unbalance parameters were easily obtained through the interval expanding operation. The efficiency and robustness of the proposed method were verified on a test rig.