THERMAL SCIENCE

International Scientific Journal

TEMPERATURE RISE IN INDUCTION MOTOR WINDINGS AS THE CAUSE OF VARIATION IN ROTATIONAL SPEED OF AN AXIAL FAN

ABSTRACT
The paper presents results of an experimental investigation performed under controlled laboratory conditions, in order to identify real causes of variation in the rotational speed of an axial fan that can be noticed after a certain period following the start of operation. The theoretical background important for understanding the observed phenomenon is given and the hypothesis is proposed which states that the temperature rise in motor windings and a consequential rise of their resistances are responsible for such specific behavior of the axial fan. The experiment was performed on a standard test rig with a small industrial axial fan, driven by a three-phase induction motor with the rated power of 1.5 kW. The experimental procedure is described in details, measured and calculated results are presented and appropriate conclusions are given. The obtained experimental results confirm the proposed hypothesis.
KEYWORDS
PAPER SUBMITTED: 2016-04-25
PAPER REVISED: 2016-07-28
PAPER ACCEPTED: 2016-09-21
PUBLISHED ONLINE: 2016-12-25
DOI REFERENCE: https://doi.org/10.2298/TSCI16S5449S
CITATION EXPORT: view in browser or download as text file
THERMAL SCIENCE YEAR 2016, VOLUME 20, ISSUE Supplement 5, PAGES [S1449 - S1459]
REFERENCES
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© 2021 Society of Thermal Engineers of Serbia. Published by the Vinča Institute of Nuclear Sciences, Belgrade, Serbia. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International licence