Thermographic Method for Measuring Insulation Fault and Loss Density on Laminated Cores

No Thumbnail Available
Journal Title
Journal ISSN
Volume Title
Sähkötekniikan korkeakoulu | Master's thesis
Ask about the availability of the thesis by sending email to the Aalto University Learning Centre oppimiskeskus@aalto.fi
Date
2017-03-13
Department
Major/Subject
Electrical Power and Energy Engineering
Mcode
ELEC3024
Degree programme
AEE - Master’s Programme in Automation and Electrical Engineering (TS2013)
Language
en
Pages
42 + 7
Series
Abstract
In this thesis work, a measurement system was developed for detecting insulation fault and loss density estimation in laminated electrical steel sheet, based on the principles of thermography. Comsol simulation of the measurement process was carried out to show the effect of temperature plot region on the accuracy of loss density estimation. The application of the measuring system was demonstrated in two cases; firstly, insulation fault caused by burr contacts created on the cutting edges of laminated steel sheet was measured. DC current was supplied to 10 stacked pieces of laminated steel sheets compressed with a force of 2500 N for 5 seconds. IR camera was used to capture the surface of the sample and the images obtined was visibly analyzed. The temperature rise curves were compared with the simulation results. In the second experiment, a 24/12 V 50 Hz transformer was supplied at 300 Hz under no-load condition for 30 seconds. IR camera was use to obtain the images of the core at the instant of supply for three different flux densities. The core losses where estimated from the gradient of temperature rise and compared with the no-load power loss obtained directly from the power analyser. The results show that the developed system can accurately detect insulation fault and estimate loss density over a wide range, with error margin of less than 6%. However, the accuracy of the results obtained is affected by measurement condition.
Description
Supervisor
Arkkio, Antero
Thesis advisor
Shah, Sahas Bikram
Keywords
fault detection, insulation, IR camera, loss density, thermography
Other note
Citation