Year: 2007
Type: dissertation
Abstract: In this research, tire dynamics of a typical ciass of hydraulic actuators is stucliecl ancl actuator leakage Fault Detection and Isolation (FDI) schemes are proposecl basecl on the Extended Kalman Filtering (EKF) aigorithrn.A clynanic moclel of the hyclrar,rlic actuation test rig combinecl rvith ari actuator li'iction model is lilst derived.The palauretels of t,he fi'ictiorl model are obtairred by carefirl experitnents.Simulations conclucted to validate the moclel shows that the sirnulation errors are bounded within I0% of actuai rneaslrrements and, within the nornai operating banclwidth, the clynauric model acleqr-rately represents the actuator used in the test rig.Based on the validated dynamic moclel., an oflline actuator leakage fault detection scherne employing EKF algorithm is clevelopecÌ.Sirrrulations ancl experiurents are carried out to velifi, the effectiveness of the ploposecl FDI scheme without the presence of external disturbance.With a residual generation scheme that cornpaled the actual tneastlretneuts and the EKF estimates, three types of leakagethe cylinder charnber leahage at eitirer sicle of the actuator and the leahage betu'een the tu,o chanrbers - are tested.The leakage faults are detected and identified ì:y tracking the variation of the residual errors and an offline actu¿rtor-FDI scheme is clevelopecl.Tire leakage ideritification patterns are recognized.To further study the performance of the EKF based FDI scheme in normal operat- Abstract ing conditions rvith external disturbances, the system model is irnproved to estirnate any arbitrary load.Actuator friction is regarclecl as part of the external disturbance in this phase and, together with the environmental loacl, becomes a tirne-varying parameter of the systen.Simulations ancl experiments show that the external load, including the actuator friction, can be accuratell, estirrratecl.Different types of testing signals ale applied to investigate the effectiveness of the FDI schenre.Exper-iments shorv that the leakage fault identification patterns ai'e consistent r,vith the conclu- sion obtained in the unloacled mode.A potential o¡rline FDI scheme and an offiine actuator friction estimator are further proposed.t11 support thr:oughout the course of this research.N4y gratitude also goes to professors Steve Onyshko ancl Waldemar H
Source: Mspace (University of Manitoba)
Author: Liang An
Language: English
Subfield: Control and Systems Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W2790689648