Model—based fault diagnosis of a pump-displacement-controlled actuator with a multidisciplinary approach using bond graph

M Toufighi,F Najafi,S Sadati

doi:10.1260/1750-9548.4.1.51

Abstract

In this chapter, firstly, the pump-displacement-controlled actuator system with applications in aerospace industries is modeled using the bond graph methodology. Secondly, an approach is developed towards simplification and model order reduction for bond graph models that can usually use in conceptual representation or design procedures. The model order reduction process indicates which system components have the most bearing on the frequency response, and the final model retains structural information. Finally, the state space form of mathematical model of the system based on the bond graph model is presented. By associating bond graph model, it becomes possible to design fault detection and isolation (FDI) algorithms, i.e. the generation of fault indicators, and to improve monitoring of the actuator.

Highlights

An important aspect of mechatronic systems is that the synergy realized by a clever combination of a mechanical system and its embedded control system leads to superior solutions and performances that could not be obtained by solutions in one domain
The method presents the unique feature of being able to model systems in different energy domains using the same approach with a single model, it becomes ideal for modeling and simulation of mechatronics and control systems
Because of the multi-domain energies involved in the actuators, the bond graph methodology as a multidisciplinary and unified modeling language proves a convenient tool for the given purpose

Summary

INTRODUCTION

An important aspect of mechatronic systems is that the synergy realized by a clever combination of a mechanical system and its embedded control system leads to superior solutions and performances that could not be obtained by solutions in one domain. The causal properties of the bond graph methodology can help to derive state space form of the governing equation of the system and design fault detection and isolation (FDI) algorithms, i.e. the generation of fault indicators (Ould Bouamama et al, 2005); (Khemliche et al, 2006) In this way, by associating bond graph models, it becomes possible to obtain the behavioral knowledge of the actuator, and to improve their monitoring. (Toufighi et al, 2007) In this manner, each sub-system constituting the electro-hydraulic actuator can be separately modeled through power variables (efforts and flows) and parameters used in these submodels are introduced in tables 2 and 3 respectively. The matrix form of the state space equations of the system is Figure 5 Simplified bond graph model of the system

FAULT DIAGNOSIS ANALYSIS USING DETECTORS IN BOND GRAPH MODEL

CONCLUSION