Reducing Eddy Current Losses in the Tank-Wall of Pad-Mounted Transformers

Pad-mounted transformers, offering flexibility and dependability, are ideal for applications in public access areas where safety is a concern. These transformers obviate the need for protective fencing or vaults, allowing for visually pleasing installation in locations that are accessible to the general public. Energy losses in these transformers give rise to local overheating and affect their safety, reliability and power delivery. One of the important sources of their energy loss is due to eddy current losses. Reducing these losses is an important issue in the design of pad-mounted transformers. This can be done through various methods usually by modifying the transformer core or/and the tank-wall, while the latter is more cost effective. One of these/ methods is the internal shielding of the tankwall of the transformer. This paper presents a new shielding technique based on the use of a special shield plate located near the highcurrent phases of the tank-wall (i.e., lowvoltage bushings). This technique is performed and verified for a 3 phases 630KVA pad-mounted transformer and experimental results show the 11.51% reduction of the load loss, with a little increase in the cost of the transformer. It is also shown that the proposed method has financial advantages for customers.

کلیدواژه ها:

Pad-mounted transformer ، Eddy current loss ، Stray loss ، Tank-wall shielding