A Multimode Anomaly Detection Method Based on OC-ELM for Aircraft Engine System

Abstract

The practical industrial processes possess the characteristics of multimode, unbalanced data distribution, and complex types of abnormalities, which are challenging to the anomaly detection task of complex industrial systems. In this paper, a novel anomaly detection framework based on one-class extreme learning machine (OC-ELM) for the multimode system is presented. To tackle the multiple operation modes, a clustering algorithm is first applied to distinguish the operation modes of the system. The corresponding detection models are built under different operation modes resulting in the multiple models operated in parallel. In addition, the proposed method constructs the reasonable boundary of the complex data distribution, reflecting the equipment running in the healthy or the normal state. The anomaly detection index is obtained according to the deviation degree between the testing sample and the normal model. As a result, a global monitoring index reflecting the degradation state is obtained by combining the anomaly monitoring indices of the equipment under multiple operation modes. The proposed method is verified on a public dataset of aircraft engines, and the advantages are demonstrated by comparing with the implemented detection model without handling the information of operation modes, and the multiple principal component analysis method.

Keywords

• Aircraft engine system
• anomaly detection
• global monitoring index
• multiple operation modes
• OC-ELM