A Fault Estimation Method Based on UIO Robust Residual Generators

Yongjin Liu,Gang Feng,Bo Zhang,Zhonghui Jia,Wenfeng Wang,Lin Zhang,T.-T Lie,E Calabrò,M Eissa

doi:10.1051/matecconf/20165503003

Abstract

This paper proposed a fault estimation method based on robust residual generators for a linear system. A system with additive actuator or component faults was considered in the case where the number of the independent faults was larger than that of the independent measurements. This method was achieved based on UIO robust residual generators and there was no need to design extra fault estimators. In this method, fault estimation was achieved via three steps. First, codingsets, which describe the sensitivity relationship between faults and generators, are designed. Second, a bank of robust residual generators are designed according to the coding sets. Finally, fault estimation is achieved by using the result of fault isolation and the output of robust residual generators. A sufficient condition on the application of the method was given and the asymptotic convergence property of the estimation error by using the method was proved. Simulation results demonstrate the effectiveness of the method.

Highlights

In recent years, with the rapid development of technologies, different kinds of systems are more complicated, and faults are easier to happen at the same time
As one of the model-based fault diagnosis techniques, the fault diagnosis technique based on robust residual generators is able to combine uncertainty of system and take full advantage of system’s deep information, which is good for fault detection, fault identification, and fault isolation
When the number of the input channel independent faults(mainly include additive actuator and component faults) less than that of the independent measurements in linear system, in this paper, a fault estimation method based on UIO robust residual generators and suitable conditions were given, and achieved fault isolation and estimation

Summary

Introduction

With the rapid development of technologies, different kinds of systems are more complicated, and faults are easier to happen at the same time. Et al designed UIO-based fault estimation method in the case where the number of the independent faults was larger than that of the independent measurements, and it needs derivative of output, but derivative of output is hard to get[9]. In order to estimate actuator faults, Hamayun et al designed sliding mode observer, but it requires the number of the independent faults was larger than that of the independent measurements[10] These two methods are both have limitations, and hard to meet requirements. When the number of the input channel independent faults(mainly include additive actuator and component faults) less than that of the independent measurements in linear system, in this paper, a fault estimation method based on UIO robust residual generators and suitable conditions were given, and achieved fault isolation and estimation

Problem Formulation

Fault Estimation

Fault Detection Strategy

Fault Estimation Strategy

Simulation Results

Conclusion