基于新的威布尔分布参数估计法的设备寿命可靠性分析

针对机械设备寿命可靠性分析中模型的精度问题,提出一种联合最小二乘及平均秩次估计威布尔分布参数的新方法.常用的参数估计法人为因素影响大,精度差,而且在现场使用不便.文中提出的方法有效地解决了上述问题.在采用最小二乘法对威布尔分布进行参数估计时,经验分布函数是确定寿命模型的基准,它的精度直接影响寿命模型的精度.平均秩次法根据故障样本和中止样本估计出所有可能的秩次,求出平均秩次,代入近似中位秩公式,得到经验分布函数,有效提高参数的精度.选取30台发动机,对其进行寿命可靠性分析,结果表明,该方法具有很高的准确性和实用性.

RELIABILITY LIFE ANALYSIS OF THE EQUIPMENT BASED ON NEW WEIBULL DISTRIBUTION PARAMETER ESTIMATION METHOD

According to the question of model precision in mechanical equipment reliability life analysis,a new method estimating the Weibull distribution model's parameters by combining least-sauares method and mean rank order is put forward.The usual parameter-estimation methods have disadvantages such as man-made effect,low precision and discommodious use in site,but all of them have been effectively resolved by the method that put forward.When using least-sauares method to make parameter estimation of Weibull distribution,empirical distribution function is used as the benchmark to ascertain the life model and the lifetime model's precision is directly affected by its precision.The mean rank order estimating all rank order based on fault samples and ceasing samples to calculate the mean rank order,then putting mean rank order into approximate formula of middle rank to get empirical distribution function and the parameter precision is effectively improved by this.Thirty engines were selected to progress reliability life analysis,the result showed that this method has very strong practicability and high precision.