为了准确估计高速列车转向架关键部件的机械磨损程度,提出了一种基于Copula函数的抗蛇行减振器阻尼参数蜕化率估计方法。该方法以高速列车抗蛇行减振器阻尼系数在不同蜕化率下的振动信号为研究对象,经过小波包滤波后,通过泛化高斯分布对各信号的边缘分布进行拟合,并使用Gaussian Copula函数构建不同蜕化率下的信号与车辆正常时信号的联合概率密度函数。提取联合概率密度函数的均值作为特征,并对目标信号的蜕化率进行估计。对某型高速列车转向架抗蛇行减振器不同参数蜕化率的振动信号进行实验,并与真实值进行比较。实验结果表明,在200 km/h速度下,实验误差均在范围内,表明了该方法的有效性。
To evaluate the mechanical wear degree of key component of high- speed train bogie, an approach using copula function to evaluate damping degeneration ratio of yaw damper is proposed in the paper. Vibration signals of a certain high- speed train are obtained under different degeneration ratios. The vibration signal is decomposed by wavelet packet filters first. The marginal distribu-tion function of the signal is fitted by generalized Gaussian distribution. The joint probability distribution between degenerate signal and the normal signal is computed by Gaussian Copula function. The mean of joint probability density function is extracted as the feature and the degeneration ration of target signal is evaluated. The vibration signals of different parameter degeneration ratio of high- speed train bogie yaw damper are used to do experiments using the proposed method and compared with the real degeneration ratio. Experiment results shows the error is within negative 3 percentages to 3 percentages at the speed of 200 km/h, which verifies the effectiveness of the proposed degeneration ratio evaluation method.