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Title: Detection of Rooftop Cooling Unit Faults Based on Electrical Measurements

Abstract

Non-intrusive load monitoring (NILM) is accomplished by sampling voltage and current at high rates and reducing the resulting start transients or harmonic contents to concise ''signatures''. Changes in these signatures can be used to detect, and in many cases directly diagnose, equipment and component faults associated with roof-top cooling units. Use of the NILM for fault detection and diagnosis (FDD) is important because (1) it complements other FDD schemes that are based on thermo-fluid sensors and analyses and (2) it is minimally intrusive (one measuring point in the relatively protected confines of the control panel) and therefore inherently reliable. This paper describes changes in the power signatures of fans and compressors that were found, experimentally and theoretically, to be useful for fault detection.

Authors:
; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
884821
Report Number(s):
PNNL-SA-48193
TRN: US200616%%52
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: HVAC & R Research; Journal Volume: 12; Journal Issue: 1
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; BLOWERS; COMPRESSORS; DETECTION; HARMONICS; MONITORING; SAMPLING; ELECTRICAL TRANSIENTS; ELECTRICAL FAULTS; COOLING SYSTEMS; ROOFS

Citation Formats

Armstrong, Peter R., Laughman, C R., Leeb, S B., and Norford, L K.. Detection of Rooftop Cooling Unit Faults Based on Electrical Measurements. United States: N. p., 2006. Web. doi:10.1080/10789669.2006.10391172.
Armstrong, Peter R., Laughman, C R., Leeb, S B., & Norford, L K.. Detection of Rooftop Cooling Unit Faults Based on Electrical Measurements. United States. doi:10.1080/10789669.2006.10391172.
Armstrong, Peter R., Laughman, C R., Leeb, S B., and Norford, L K.. Tue . "Detection of Rooftop Cooling Unit Faults Based on Electrical Measurements". United States. doi:10.1080/10789669.2006.10391172.
@article{osti_884821,
title = {Detection of Rooftop Cooling Unit Faults Based on Electrical Measurements},
author = {Armstrong, Peter R. and Laughman, C R. and Leeb, S B. and Norford, L K.},
abstractNote = {Non-intrusive load monitoring (NILM) is accomplished by sampling voltage and current at high rates and reducing the resulting start transients or harmonic contents to concise ''signatures''. Changes in these signatures can be used to detect, and in many cases directly diagnose, equipment and component faults associated with roof-top cooling units. Use of the NILM for fault detection and diagnosis (FDD) is important because (1) it complements other FDD schemes that are based on thermo-fluid sensors and analyses and (2) it is minimally intrusive (one measuring point in the relatively protected confines of the control panel) and therefore inherently reliable. This paper describes changes in the power signatures of fans and compressors that were found, experimentally and theoretically, to be useful for fault detection.},
doi = {10.1080/10789669.2006.10391172},
journal = {HVAC & R Research},
number = 1,
volume = 12,
place = {United States},
year = {Tue Jan 31 00:00:00 EST 2006},
month = {Tue Jan 31 00:00:00 EST 2006}
}
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