Full metadata record
|dc.contributor||Department of Building Services Engineering||en_US|
|dc.contributor.advisor||Deng, Shiming (BSE)||-|
|dc.creator||Tse, Yau Ki||-|
|dc.publisher||Hong Kong Polytechnic University||-|
|dc.rights||All rights reserved||en_US|
|dc.title||Improvement of a new adaptive controller for the variable speed direct expansion air conditioning system with an emphasis on system stability||en_US|
|dcterms.abstract||The operational instability of refrigeration system has been studied over decades. It will lead to a lower operational safety, and a higher energy consumption of a refrigeration system There have been two different views on the possible causes of operational instability of refrigeration system or known as hunting. The first of the view is the inherent operational characteristics of an evaporator, the observation of the fluctuation in refrigerant mixture-vapor transition point. The second view is the inherent operational characteristics of an expansion valve (EV). Hunting is observed both in thermostatic expansion valve (TEV) controlled refrigeration system e.g. time constant of the evaporator pipe wall and electronic expansion valve (EEV) controlled refrigeration system e.g. nonlinearities in response from control input. On the other hand, an adaptive controller is reported based on the relationship between the inherent operational characteristics and the operational stability for an experimental variable speed (VS) direct expansion (DX) air conditioning (A/C) system. The adaptive controller was then validated using an experimental VS DX A/C system. The results showed that the parameters of PID controller will be changed at different supply fan speeds to improve the stability of DS setting in the DX A/C system||en_US|
|dcterms.extent||13, 71 pages : color illustrations||en_US|
|dcterms.LCSH||Hong Kong Polytechnic University -- Dissertations||en_US|
|dcterms.LCSH||Air conditioning -- Control||en_US|
|dcterms.LCSH||Refrigeration and refrigerating machinery||en_US|
Files in This Item:
|991022168751003411.pdf||For All Users (off-campus access for PolyU Staff & Students only)||1.99 MB||Adobe PDF||View/Open|
As a bona fide Library user, I declare that:
- I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
- 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.
- 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.
Please use this identifier to cite or link to this item: