变核函数的WVD在汽车轴承故障检测中的应用

由于轴承各个阶段的故障信号存在一定差异,且固定核函数的维格纳分布(WVD)无法适应不同类型的信号,为此,提出利用可变核函数平滑伪WVD对汽车轴承故障进行检测。建立WVD的特征函数,利用特征函数的聚散性抑制交叉项干扰;在此基础上,将不同类型信号核函数的确定转化为最优化化问题,并给出核形状与核参数协同优化的关系式。采用变核平滑方法的WVD对汽车轴承故障进行检测,结果表明:变核函数的平滑WVD对信号的适应性更强,且能有效抑制交叉项振荡,在计算成本略有增加的基础上,检测准确率达到了97%以上。

Application of WVD with Variable Kernel Function in Fault Detection of Vehicle Bearings

Because the bearing fault signal in various stages had some differences, and Wigner-Ville distribution with fixed kernel function could not adapt to different types of signals, pseudo WVD smoothened by variable kernel function was proposed to detect vehicle bearing fault. The characteristics function of the WVD was established and its cross term interference was restrained by using the convergence of the characteristic function.On the basis,determination of different kernel functions was converted to optimization problems. Then the relation of collaborative optimization of kernel function shape and parameters were given.WVD with variable kernel was adopted to detect vehicle bearing fault.The results show that WVD with variable kernel has a stronger adaptability to signals and it can effectively restrain the oscillation of cross terms. The detection accuracy can reached more than 97% with micro growth of the calculation cost.