模鑄式變壓器散熱行為之研究

A Study on the Behavior of Heat Dissipation of a Cast Resin Transformer

蔡巧翔(Chiao-Hsiang Tsai)

指導教授 ： 鄧治東

中原大學/工學院/機械工程研究所/碩士(2005年)

https://doi.org/10.6840/cycu200500005

摘要

對電力系統設備設計者而言，如何精確得知該系統內最大温度值與其位置係屬重要，而模鑄式變壓器使用年限與其壽命，與此兩項參數有著密切關係。
模鑄式變壓器所使用的樹脂絕緣材料，將隨其本身温度的升高或環境温度改變而熱劣化，機械強度遂逐漸降低，最後只要稍受外力影響，其絕緣物即裂化，造成變壓器燒毀或破壞，因此為確保變壓器本身之壽命，預防異常之劣化，如何了解系統流場中之最熱點的區域係屬必要。
本論文係以一模鑄型變壓器為研究系統，分析工作流體（空氣）在流道內之自然對流行為，並找出其熱點發生位置，其幾何模型為一模鑄式變壓器於開放空間中，其自然對流散熱情形。本文使用Icepak 分析軟體，於設定不同邊界條件下，以了解其系統温度分佈情形，並與實際量測數據驗證，期許未來於相關變壓器散熱設計有所助益。

關鍵字

散熱分析 ； Icepak 分析軟體 ； 模鑄式變壓器 ； 損失

並列摘要

To accurately determine the level and the location of peak temperature within a power-supply system is essential for the system equipment designers. In addition, these parameters are closely related to the life-span of the equipment, in particular, the case-resin transformers.

The resin insulation material used in the case-resin transformers becomes thermally degraded due to the elevated temperature it encounters or a change in the level of the environmental temperature it exposes to. As a result of the thermal degradation, the mechanical strength of the material is weakened, leading to cracking of the insulation material once an external force is exerted on it causing the transformer to be burned or damaged. Thus, to ensure a proper life-span of the transformer and to prevent abnormal degradation of it, understanding of the flow field and the location of the hot-point within it becomes an important issue to be dealt with.

This thesis investigated a case-resin transformer system for the natural-convection behavior of the flow channels and for the location of the hot-spot within the system. Its geometrical configuration was modeled using a case-resin transformer exposed to an open-air with natural convection to be the heat transport mechanism for dissipating the heat generated by the system.

The study used Icepak software package, which was developed using the computational fluid dynamics (CFD) technique with the algorithm of finite volume method, for the analyses to determine the temperature distributions in the system by specifying a variety of boundary conditions. The numerically predicted results were then verified with the experimental data obtained by laboratory tests. The comparison indicated that reasonable agreements were achieved. It is expected that the work done and the results obtained by this study will be beneficial for the future study of thermal management of the related heat-dissipating power transformers.

並列關鍵字

Case-Resin Transformer ； Thermal Management ； Icepak Software

參考文獻

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