Full metadata record
DC FieldValueLanguage
dc.contributorDepartment of Building Services Engineeringen_US
dc.creatorYao, Cheng-
dc.publisherHong Kong Polytechnic University-
dc.rightsAll rights reserveden_US
dc.titleLighting calculations for LED systemsen_US
dcterms.abstractAlong with people's increasing awareness of energy conservation and environmental protection, lighting consumption, occupying a certain and stable percentage of total consumption, about 15%, leads to a new technological revolution. As a lamp substitute for new generation of domestic lamp, LEDs play a significant role undoubtedly. The advent and generalization of white LEDs, LED finally step into a period of civilian use. Along with the advantages such as eco-friendly, highly efficient, long service life, and harmless, LED also faces the disadvantage, the too much investment in early stage of new products. With the technology promoted and the cost reduced, the initial investment will drop naturally, at the same time, the benefits will grow gradually. However, public always cannot distinguish the concepts of luminaire efficacy and the lamp efficiency, which often mislead consumers, at the same time, it also confuse the some producers and sellers. Manufacturer always boast how outstanding their products are, while fail to regard actual experience of consumers. Indeed, due to the unclear definition and based on the present calculations, the procedure of calculating the indoor illuminance using calculation refer to utilization factor method may lead to chaos. Because the lamp and luminaire of LED is a whole that can hardly be separated, which will lead to overheating and unstable when it separated, therefore we cannot define the number of lumens emitted from lamp. In this paper, by analyzing the calculation refer to utilization factor, re-defines the concepts, which is applicable to LEDs calculation, and luminaire of calculation consistently, and get a correct calculation method to calculate utilization factors of LEDs. Through related calculations in EXCEL and simulations in DIALux of seven samples, several groups of data have been compared and analyzed. According to a series of analyses and calculations, this paper puts forward the relationship between the new utilization factor based on luminaire lumen output and the old utilization factor based on lamp lumen output. The new method is proved by author, and some comments are given.en_US
dcterms.extentxv, 109 leaves : ill. (some col.) ; 30 cm.en_US
dcterms.isPartOfPolyU Electronic Thesesen_US
dcterms.educationalLevelAll Masteren_US
dcterms.LCSHLight emitting diodes.en_US
dcterms.LCSHLight emitting diodes -- Energy consumption.en_US
dcterms.LCSHHong Kong Polytechnic University -- Dissertationsen_US
dcterms.accessRightsrestricted accessen_US

Files in This Item:
File Description SizeFormat 
b26411234.pdfFor All Users (off-campus access for PolyU Staff & Students only)4.46 MBAdobe PDFView/Open

Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show simple item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/7121