基于方差约束控制的复杂控制系统故障诊断方法

将方差约束控制用于研究复杂控制系统故障诊断。首先根据系统运行情况提取故障点在各个子系统的状态观测值,定义了故障点的状态观测均值、误差并求得状态协方差。然后通过熵系数法来确定各影响因素的权重,用欧氏范数法和线性加权法确定系统正常运行的最大允许阈值,一旦实际值超过阈值则报警,采取修正措施。最后通过实例,得到了一种新的基于欧氏范数方差约束控制的故障诊断方法,应用于航天产品漏电故障诊断。结果表明,该方法的故障阈值是由系统本身特性得到,故能够客观、真实地确定阈值的量化模型,克服了传统的专家系统需要训练大量历史数据的弊端,实现了故障在线实时诊断。

Fault Diagnosis Based on Covariance Constraint for Complex Control Systems

The covariance constrain method is proposed for fault diagnosis of complex control systems.First of all,the state observe values of fault-spot at the sub-systems are extracted in accordance with the running circumstances of system,then the parameter structure of the average and error for state observe values are defined and the covariance is gained.Secondly,the weight of the subsection state is obtained by entropy method,the threshold value is confirmed from the Euclidean norm and the linear weight.Once the threshold value is exceeded by the practice data,the alarm is given,the system modification is adopted.Finally,a new fault covariance constraint control diagnosis method based on the Euclidean norm is got through example and is applied to spaceflight model creepage fault diagnosis.Comparsion between the method and the conventional fault diagnosis shows the threshold value mode can be built impersonally and really.Fault real time online diagnosis is realized.