AAU Student Projects - visit Aalborg University's student projects portal
A master's thesis from Aalborg University
Book cover


Fault Detection and Isolation for a Supermarket Refrigeration System

Authors

;

Term

10. term

Publication year

2009

Pages

137

Abstract

Dette speciale, udført ved Aalborg Universitet Esbjerg, undersøger, hvordan man kan detektere og isolere almindelige fejl i en kølemontre i supermarkeder. Med en grundmodel af kølesystemet leveret af Danfoss A/S tester og sammenligner vi flere modelbaserede metoder: Kalman-filteret (estimerer den sande tilstand ud fra støjende sensordata), det Udvidede Kalman-filter (til systemer med ikke-lineær adfærd) og en Observer for ukendte input (håndterer ukendte forstyrrelser). Vi afprøver også en simpel online parameterestimering; de første resultater var lovende, men metoden blev ikke færdiggjort inden for projektets tidsramme. På baggrund af sammenligningerne foreslår vi et fejl-detektion-og-isolation-setup, som kan opdage og adskille de hyppigst forekommende fejl i kølemontre.

This thesis, carried out at Aalborg University Esbjerg, investigates how to detect and isolate common faults in a supermarket refrigerated display case. Using a base model of the refrigeration system supplied by Danfoss A/S, we test and compare several model-based methods: the Kalman Filter (estimates the true system state from noisy sensor data), the Extended Kalman Filter (for nonlinear behavior), and an Unknown Input Observer (accounts for unknown disturbances). We also evaluate a simple online parameter estimation approach; initial results were promising, but the method was not completed within the project time. Based on the comparisons, we propose a fault detection and isolation setup that can identify and separate the most frequent faults in display cases.

[This abstract was generated with the help of AI]