本文關鍵詞：電力變壓器繞組短路電動力計算　出處：《哈爾濱理工大學》2014年碩士論文　論文類型：學位論文

  更多相關文章： 電力變壓器 電磁場分布 場路耦合 短路電動力 繞組機械強度

【摘要】：電力變壓器在電網(wǎng)中主要起到能量轉換和傳輸?shù)淖饔�，是發(fā)電廠和變電所的重要設備之一，其承受短路能力的大小直接關系到電網(wǎng)是否能夠安全可靠的運行。隨著國民經(jīng)濟的快速發(fā)展以及國家對電網(wǎng)的不斷投建和改造，使得越來越多的大型電力變壓器在電網(wǎng)中被投入使用，但在其運行過程中當變壓器受到短路沖擊電流作用時因繞組的機械強度不足而引起的事故屢見不鮮。因此，提高大型電力變壓器繞組抗短路能力是需要解決的問題。 本文以一臺三相五柱式電力變壓器為例，對其內部瞬態(tài)電磁場、繞組短路電動力以及線圈的機械強度問題進行了深入的分析研究。介紹了本課題的研究背景和意義，闡述了大型電力變壓器內部電磁場、繞組短路電動力以及繞組機械強度問題的國內外發(fā)展情況。對樣機建立三維有限元模型，利用場路耦合方法計算了此模型在額定運行和短路運行兩種不同情況下變壓器三維瞬態(tài)電磁場的磁密分布及繞組靜態(tài)時軸向和輻向的受力大小，并給出其分布規(guī)律。與此同時，針對電力變壓器繞組在其高度方向上的機械強度問題進行了商討，建立了變壓器低壓繞組在Z軸方向上的模態(tài)振動數(shù)學模型，計算了在短路沖擊力的作用下繞組線餅軸向上產(chǎn)生的位移變化及引起的共振頻率大小，并針對繞組的短路電動力進行了校核。此課題為加強繞組承受短路能力的設計提供了一定的理論依據(jù)，，為今后類似的研究提供了參考依據(jù)，具有一定的理論和工程應用價值。
[Abstract]:Power transformers play an important role in energy conversion and transmission in power grid, and are one of the important equipments in power plants and substations. Its ability to bear short circuit is directly related to whether the power grid can operate safely and reliably. With the rapid development of the national economy and the continuous investment and reconstruction of the power grid. As a result, more and more large power transformers are put into use in the power grid. However, when the transformer is affected by short-circuit impact current during its operation, accidents caused by insufficient mechanical strength of windings are common. To improve the short-circuit resistance of large power transformer windings is a problem to be solved. Taking a three-phase five-column power transformer as an example, the transient electromagnetic field inside the transformer is studied. The short circuit electromotive force of winding and the mechanical strength of the winding are deeply analyzed and studied. The research background and significance of this subject are introduced, and the electromagnetic field inside the large power transformer is expounded. The development of windings short circuit electromotive force and winding mechanical strength at home and abroad. The 3D finite element model of the prototype is established. The field circuit coupling method is used to calculate the magnetic density distribution of the three dimensional transient electromagnetic field of the transformer and the axial and radial force under static winding under two different conditions of rated operation and short circuit operation. At the same time, the mechanical strength of the power transformer winding in the direction of its height is discussed, and the mathematical model of the modal vibration of the low-voltage winding of the transformer in the Z-axis direction is established. The displacement change and resonance frequency caused by the axial direction of the winding wire cake under the action of short circuit impact force are calculated. The short circuit electromotive force of the winding is checked. This subject provides a certain theoretical basis for the design of strengthening the short circuit bearing capacity of the winding, and provides a reference basis for similar research in the future. It has certain theory and engineering application value.
【學位授予單位】：哈爾濱理工大學
【學位級別】：碩士
【學位授予年份】：2014
【分類號】：TM41

【引證文獻】

相關期刊論文 前2條

1 樊益平;張軍;張海龍;賀好艷;馬奎;丁培;;變阻抗節(jié)能變壓器的動熱穩(wěn)定性能研究[J];高壓電器;2017年01期

2 王洋;曹晨;徐建源;;基于磁-結構耦合法的變壓器繞組振動特性研究[J];電工電氣;2016年02期

相關碩士學位論文 前3條

1 王洋;電力變壓器運行狀態(tài)下振動特性研究[D];沈陽工業(yè)大學;2016年

2 李大華;整流變壓器繞組漏磁計算及線圈結構優(yōu)化[D];南昌大學;2015年

3 王雪婷;基于微槽群復合相變冷卻技術的變壓器短路溫度特性研究[D];湖南大學;2015年

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