【摘要】：近來,國(guó)內(nèi)經(jīng)濟(jì)的高速運(yùn)轉(zhuǎn)使得各大工業(yè)的電力用量在劇烈增加,如何滿足工業(yè)電力用電量,成為了國(guó)家電網(wǎng)下一步工作的重點(diǎn),從而加快了特高壓輸變電技術(shù)的成長(zhǎng)。其特點(diǎn)是容量大、傳輸距離遠(yuǎn)。特高壓交流變壓器是該技術(shù)變?yōu)楝F(xiàn)實(shí)的必備設(shè)備,在整個(gè)電力變壓器領(lǐng)域中,該變壓器技術(shù)含量高、制造難度大、各方面要求限制多。雙百萬變壓器因?yàn)槠浼夹g(shù)復(fù)雜、容量大、電壓等級(jí)為世界最高,因此帶來的問題是其損耗大,對(duì)其溫升的研究成為國(guó)內(nèi)外電工裝備業(yè)重點(diǎn)關(guān)注的問題之一。負(fù)載損耗作為變壓器最主要的性能參數(shù)之一,由多個(gè)損耗分量組成。這些損耗均提供熱源,熱源的大小以及分布,都會(huì)直接或者間接影響變壓器熱點(diǎn)溫升的分布。由于雙百萬變壓器容量大,導(dǎo)致其尺寸也較大,為滿足運(yùn)輸過程中的尺寸限制,導(dǎo)致了變壓器單位損耗大,從而造成了內(nèi)部散熱較困難。所以該變壓器進(jìn)行設(shè)計(jì)面臨的技術(shù)難題之一是,如何對(duì)繞組直阻產(chǎn)生的熱量、冷卻特性及繞組溫升如何進(jìn)行準(zhǔn)確計(jì)算和分析。所以對(duì)雙百萬變壓器不同工況下繞組內(nèi)部的油流速度分布以避免油流帶電,對(duì)繞組溫度以及其熱點(diǎn)分布特點(diǎn)進(jìn)行研究和改進(jìn)是非常有工程應(yīng)用價(jià)值的,而溫升及熱點(diǎn)溫升降低后,可明顯提高變壓器的絕緣壽命。在特高壓變電站中,目前應(yīng)用比較典型的是雙百萬(容量為lOOOOOOkVA、電壓為1000000V)特高壓電力變壓器,簡(jiǎn)稱為雙百萬變壓器。本文就針對(duì)該雙百萬變壓器的主體變的負(fù)載損耗的在各個(gè)線圈中各餅的分布、油流冷卻結(jié)構(gòu)及不同冷卻器的工作狀態(tài)、繞組以及熱點(diǎn)溫升問題進(jìn)行了較深入的理論計(jì)算分析以及試驗(yàn)研究。首先,采用初步設(shè)計(jì)方案,基于美國(guó)SOFTTEAM公司開發(fā)的TranCalc集成計(jì)算軟件,對(duì)該變壓器繞組溫升及熱點(diǎn)溫升進(jìn)行了計(jì)算,對(duì)各繞組中熱點(diǎn)溫升超過限制的原因進(jìn)行分析,針對(duì)具體情況,給出了解決措施。其次,研究了該變壓器的油流結(jié)構(gòu),建立了三維流動(dòng)模型,對(duì)不同冷卻器對(duì)于整個(gè)變壓器內(nèi)部油流流動(dòng)的貢獻(xiàn)進(jìn)行了分析研究,并提取了進(jìn)入器身的平均流速為二維繞組的溫升計(jì)算提供邊界條件。再次,通過建立雙百萬變壓器的二維繞組模型,利用大型商用CFD(計(jì)算流體動(dòng)力學(xué),Computational Fluid Dynamics)、傳熱學(xué)等的理論,應(yīng)用流、固耦合的方法,對(duì)繞組內(nèi)部流速以及溫升進(jìn)行了計(jì)算。最后,對(duì)雙百萬變壓器溫升試驗(yàn)接線原理以及試驗(yàn)過程進(jìn)行了介紹。推過公式法和外推法對(duì)溫升試驗(yàn)數(shù)據(jù)進(jìn)行處理,并分別與不同軟件計(jì)算的繞組溫度梯度進(jìn)行了對(duì)應(yīng)的對(duì)比,并對(duì)其差異進(jìn)行了說明,為后續(xù)深入研究奠定了基礎(chǔ)。
[Abstract]:Recently, with the rapid operation of domestic economy, the power consumption of each major industry is increasing dramatically. How to meet the industrial electric power consumption has become the focus of the next step of the State Grid, thus speeding up the growth of UHV transmission and transformation technology. It is characterized by large capacity and long transmission distance. UHV AC transformer is the necessary equipment for this technology to become a reality. In the whole field of power transformer, the transformer has high technology content, high manufacturing difficulty and many requirements. Because of its complex technology, large capacity and the highest voltage grade in the world, the double million transformer has the problem of high loss, and the research on its temperature rise has become one of the most important problems in the field of electrical equipment at home and abroad. As one of the most important performance parameters of transformer, load loss is composed of multiple loss components. These losses all provide heat source, the size and distribution of heat source will directly or indirectly affect the distribution of transformer hot spot temperature rise. Due to the large capacity of double million transformer, its size is also large. In order to meet the size limitation in transportation process, the unit loss of transformer is large and the internal heat dissipation is difficult. Therefore, one of the technical problems in the design of the transformer is how to accurately calculate and analyze the heat generated by the direct resistance of the winding, the cooling characteristics and the temperature rise of the winding. Therefore, it is very valuable to study and improve the winding temperature and its hot spots distribution of oil flow velocity in the windings under different working conditions in order to avoid the oil flow electrification. However, the insulation life of transformers can be improved obviously after the decrease of temperature rise and hot spot temperature rise. At present, the typical application of UHV substations is double million UHV power transformers (lOOOOOOkVA, voltage 1000000V). In this paper, the distribution of each cake in each coil, the cooling structure of oil flow and the working state of different coolers for the main variable load loss of the double million transformer are discussed. The theoretical analysis and experimental study on the winding and hot spot temperature rise are carried out. First of all, based on the TranCalc integrated calculation software developed by SOFTTEAM Company, the temperature rise and hot spot temperature rise of the transformer winding are calculated, and the reason why the hot spot temperature rise exceeds the limit in each winding is analyzed. According to the concrete situation, the solving measures are given. Secondly, the oil flow structure of the transformer is studied, the three-dimensional flow model is established, and the contribution of different coolers to the oil flow in the whole transformer is analyzed. The average velocity of the inlet body is extracted to provide boundary conditions for the calculation of the temperature rise of the two-dimensional windings. Thirdly, by establishing the two-dimension winding model of double million transformer, using the theory of large-scale commercial CFD (computational fluid dynamics, Computational Fluid Dynamics), heat transfer, etc.), applying the method of flow and solid coupling, The internal velocity and temperature rise of the winding are calculated. Finally, the connection principle and test process of double million transformer temperature rise test are introduced. The formula method and extrapolation method are used to deal with the temperature rise test data. The results are compared with the temperature gradient calculated by different software, and the differences are explained, which lays a foundation for further research.
【學(xué)位授予單位】：山東大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：TM41

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 官瀾;李光范;李博;趙志剛;李金忠;張書琦;;我國(guó)特高壓電力變壓器研制技術(shù)及發(fā)展[J];變壓器;2014年08期

2 熊蘭;趙艷龍;楊子康;宋道軍;席朝輝;何為;;樹脂澆注干式變壓器溫升分析與計(jì)算[J];高電壓技術(shù);2013年02期

3 康建洲;;主變壓器繞組熱點(diǎn)光纖測(cè)溫技術(shù)的應(yīng)用[J];電力與能源;2012年03期

4 陳偉根;蘇小平;周渠;潘，

本文編號(hào)：2320204