基于改进马氏距离的空压机健康状态评估

A health assessment method of compressor based on improved Mahalanobis distance

针对在线评估设备健康状态问题,提出了改进马氏距离结合滑动窗口的评估方法。该方法通过监测多个相关性能参数的时间序列,在马氏距离的基础上,利用改进马氏距离法将设备额定参数代替采集样本的均值求取偏离度,检测异常点。为了更好地去除瞬时故障和环境扰动,增加检测的鲁棒性,采用结合直方图及滑动窗口的方法研究包含参数历史信息的改进马氏距离时间序列,构建退化指数,评估设备的健康状态。对某制氧厂空压机的健康状态评估实例,验证了该方法的可行性和有效性。

In order to evaluate the health status of the equipment on-line,an improved Mahalanobis distance combined with sliding window evaluation method is proposed in this paper.Through monitoring the time series of multiple related performance parameters,on the basis of Mahalanobis distance,this method adopts the improved Mahalanobis distance method to obtain the mean deviation and outlier detection from the rated parameters of equipment instead of collecting samples.In order to remove transient faults and environmental disturbance,increase the robustness of the detection,the improved Mahalanobis distance time series based on histogram method and the sliding window contains the parameters of historical information,construct degradation index,and evaluate the health state of equipment.A case study of an air compressor in an oxygen plant is given to demonstrate the feasibility and effectiveness of the method.