小子样下机构系统磨损仿真可靠性研究

Reliability Research on the Mechanism System Wear Simulation under the Case of the Small-scale Sample

针对断路器机构系统具有磨损试验小子样、失效阈值不固定、试验成本高的特点,通过模拟仿真试验法、小子样数据处理法、随机性理论,对某大容量发电机断路器传动机构的磨损可靠性进行研究。在考虑运动副非规则磨损对断路器传动机构系统性能退化的影响及制造误差的基础上,基于Archard磨损模型对运动副不同接触点的磨损量进行计算,利用ADAMS仿真软件获得了该传动机构危险关节运动副服从正态分布的初始间隙量下的磨损数据。采用小子样的虚拟增广法和Boot-strap法对获得的磨损数据进行扩展,根据该机构系统磨损退化量分布规律分别得到扩展前后的可靠度函数曲线,对比结果表明对该样本进行小子样的扩展是必要的。利用扩展数据分别得到固定失效阈值、随机失效阈值下的可靠度曲线,结果表明断路器传动机构磨损随机失效阈值下的可靠度较固定阈值更接近生产实际。研究表明复杂的磨损过程可通过仿真试验预测其可靠性,从而避免了传统的必须依赖试验的研究方法,具有一定的应用价值。

Considering the characteristics that the circuit breaker mechanism system wear data is a small-scale sample,the failure threshold is not fixed and the experiment cost is very high,the simulation test method,the small-scale sample data processing method and random theory are used to research on the wear reliability of the large capacity generator breaker transmission mechanism.On the basis of considering kinematic pair irregular wear on the circuit breaker transmission system and the manufacturing error,the depth of wear on the kinematic pair different contact points is calculated based on Archard wear model,and the wear data under the case that the initial clearances of the dangerous joint kinematic pair in the circuit transmission mechanism follow normal distribution is got through ADAMS simulation software.The post-expansion data is obtained with the methods of the virtual augmentation method and boot-strap method,the reliability function curve before and after expansion of the circuit breaker are got separately according to the distribution law of circuit breaker mechanism system wear amount,the results after comparison show that the small-scale expansion is necessary.The reliability function curves under the cases of fixed threshold and random threshold are obtained separately by using the post-expansion wear data,and the comparison results show that the reliability under random threshold is more close to the actual production.The research indicates that the simulation test can be used to predicate the reliability of the complex wear process,which can avoid the traditional research method relying on the experiment,and the analytical method has certain rationality.