油浸式電力變壓器溫升之研究

Study of Temperature Rise on Oil-Immersed Power Transformers

許博聞(Bor-Wen Shu)

指導教授 ： 鄧治東

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400281

摘要

中文摘要

在變壓器的性能中，其外殼內的流場現象具有舉足輕重的影響，因此若是在瞭解與分析變壓器外殼內的流場現象方面有更進一步的發展，將有助於變壓器的設計。變壓器是一可將不同電壓系統之電能作任意有效連結之器械，也是現今工業動力的主要來源。在本研究中所使用來模擬分析一真實變壓器的Icepak計算流體力學程式，是由美國Fluent公司針對電子業模擬分析熱流現象所發展出的一套程式，該程式可用於計算暫態、二維、三維以及含有多種紊流模式之流場。

本研究使用之Icepak計算流體力學程式係以有限體積法進行數值計算，使用強大且快速的Multigrid功能與分離演算法，其提供非結構式網格處理複雜幾何模型，同時亦有操作簡易功能齊全之套裝模組以供使用者建立模型。

本研究計畫探討油浸式電力變壓器於氣冷狀態下內部自然對流之溫度與流場，並與變壓器理論計算及實際試驗佐證比對，以探討Icepak軟體利用於變壓器溫升模擬之合宜性與應用程序及法則。分析結果顯示，模擬個案在變壓器鐵心、繞組等方面均有合理之吻合度，同時推算所得之最高溫位置可做為變壓器溫度感測器設置位置之參考。此外，可進行變壓器散熱器配置方式之進階研究，提前驗得知溫升試驗結果，並減少漫長之實驗時間與降低開發該產品之成本。本文研究所建立之分析程序與法則未來將對油浸、乾式、模鑄、氣體絕緣等各式變壓器之進階研究具實質助益。

關鍵字

溫度 ； 變壓器

並列摘要

Abstract

The flow field inside the tank of a transformer has a major impact on the performance of the transformer. As a result, it is essential for the design of the device to have an in-depth understanding of the flow field. Transformer is an effective electrical device for the connection of tow power systems and a major power source for the industry.

In this study, the computational fluid dynamics (CFD) software Icepak, developed by the Fluent Company, was used to evaluate the thermal management of the various electronic devices. Icepak was based on the finite volume algorithm for the numerical simulation, with the capabilities for determining the transient, 2-D, and 3-D flow fields. It has a number of turbulence models with powerful, multi-grid and parallel numerical processing. In addition, it provides the unstructured grid generation capability to handle the complicated geometrical modeling. Furthermore, it has the easy-to-use modules for the users to choose.

This study investigated the temperature and flow fields of an oil-cooled power transformer with internally natural convection as the cooling means. The study used theoretical calculations and the numerical simulations; their respective results were compared with the experimental results. The purpose for this study was to evaluate the adequacy of the methodology and procedure by using the Icepak software package to determine the thermal management of a power transformer. The results obtained from the Icepak calculations indicated that the peak temperatures obtained for the core and the winding of transformer were in reasonable agreement with those obtained from the experimental results. In addition, the location for the peak temperature obtained from the Icepak calculations could be used for pinpointing the location of the temperature sensing devices. Furthermore, in-depth study of the arrangement of the cooling device used for the power transformer could predict valuable information of the temperature rise for the configuration under the tests. This could cut down the time and cost required for the development of the new product for the transformer.

The methodology and procedure established by this study can certainly be extended to determine the temperature and flow fields for a number of other power transformers different from the one studied in this thesis.

並列關鍵字

temperature ； transformer

參考文獻

[2] International Electrotechnical Commision, “Power Transformers Temperature Rise,” IEC 76-2, 1993.

[8] John J. Winders, Jr., “Power Transformer Principles and Applications,” Marcel Dekker, Inc., 2002.

[9] G. L. Alegi and W. Z. Black, “Real-Time Thermal Model For an Oil-Immersed, Forced-Air Cooled Transformer,” IEEE Transactions On Power Delivery, Vol. 5, No. 2, April 1990.

[10] W. H. Tang, Q. H. Wu and Z. j. Richardson, “Equivalent Heat Circuit Based Power Transformer Thermal Model,” IEE Process-Electronic Power Application, Vol. 149, No. 2, March 2002.

[11] Linden W. Pierce, “Predicting Liquid Filled Transformer Loading Capability,” IEEE Transactions On Industry Applications, Vol. 30, No. 1, Jannuary/February 1994.