| Author: | Jiao, Yizhou |
| Title: | Novel fuzzy logic controller and comparative study among fuzzy logic control, on-off control and proportional-integral control in a direct expansion air conditioning system |
| Advisors: | Deng, Shiming (BSE) Yan, Huaxia (BSE) Fang, Guanyu (BSE) |
| Degree: | M.Eng. |
| Year: | 2020 |
| Subject: | Air conditioning -- Control Hong Kong Polytechnic University -- Dissertations |
| Department: | Department of Building Services Engineering |
| Pages: | 103, [6] pages : color illustrations |
| Language: | English |
| Abstract: | This dissertation introduces a fuzzy logic control algorithm to replace the traditional on-off control algorithm which is widely applied by the direct expansion (DX) air conditioning (A/C) systems. The fuzzy logic control (FLC) law based variable speed technology enables both the compressor and the supply air fan in a DX A/C system to be continuously operated at a stepless-changed speed under the accurate temperature control. The fuzzy logic control had been proved highly effective in direct expansion air-conditioners in terms of control precision and energy saving. An improved fuzzy logic controller was developed by applying new inherent operating characteristic map containing 64 speed combinations of compressor and fan. Two experiments were conducted with an experimental DX A/C system at a simulated indoor environment, including the disturbance rejection test for fuzzy logic controller and the comparative test for the system controlled by on-off controller, PI controller and fuzzy logic controller. The experimental results indicated that fuzzy logic controller can have the best control performance in terms of control precision, response time, sensitivity and power consumption, and have a robust control stability without being influenced by the setpoint change and load disturbance. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| 5331.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 3.8 MB | Adobe PDF | View/Open |
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