| Author: | Feng, Yangqing |
| Title: | Magnetic field shielding |
| Degree: | M.Eng. |
| Year: | 2014 |
| Subject: | Magnetic shielding Office buildings -- Health aspects. Hong Kong Polytechnic University -- Dissertations |
| Department: | Department of Building Services Engineering |
| Pages: | iv, 97 leaves : color illustrations ; 30 cm |
| Language: | English |
| Abstract: | This thesis is focused on magnetic field shielding for transformer conductors and busbars in commercial buildings. With the development of economy, high-rise buildings are appearing more and more often in places like Hong Kong, which has a large population but a limited land. The large demand on AC systems leads to large demand on electricity, therefore, large transformers. EMFs usually come with electric transmission lines, cables, busway, grounding systems, and industrial equipment, transformers and switchboards. This thesis talks about associated problems of EMF; and different sources of magnetic fields including natural sources and artificial sources; mechanism of magnetic field shielding; and protective measures; modeling models on computer and program simulations using the FEM method. In the literature review, planar shielding calculation equations have been provided. From all these results, a common pattern can be observed. First of all, the size of the shielding is crucial. The bigger the shielding plate size is, the better the shielding performance. Second, when the size of the plate is the same, material becomes the key element to determine the shielding performance. The third element is the thickness of the shielding plate. The thicker, the performance is better. Applying shielding methods reduces the distance between source and usable region approximately 40-60% due to different methods or material. Therefore, shielding methods are recommended because of its high cost effectiveness. |
| Rights: | All rights reserved |
| Access: | restricted access |
Files in This Item:
| File | Description | Size | Format | |
|---|---|---|---|---|
| b27606077.pdf | For All Users (off-campus access for PolyU Staff & Students only) | 4.84 MB | Adobe PDF | View/Open |
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