本文選題：換流變壓器 + 脈動(dòng)直流電壓�。� 參考：《重慶大學(xué)》2014年博士論文

【摘要】：換流變壓器是高壓直流輸電系統(tǒng)的關(guān)鍵設(shè)備。與普通電力變壓器相比，換流變壓器的運(yùn)行工況更為嚴(yán)厲，導(dǎo)致?lián)Q流變壓器故障率高于普通電力變壓器。作者針對(duì)換流變壓器油紙絕緣可靠性評(píng)估的需要，對(duì)油紙絕緣脈動(dòng)直流電壓耐受特性、電老化過(guò)程中油紙絕緣空間電荷特性以及油紙絕緣失效模型三個(gè)方面的問(wèn)題進(jìn)行了深入研究，論文主要內(nèi)容有： ①對(duì)油紙絕緣的脈動(dòng)直流電壓耐受特性及脈動(dòng)系數(shù)與溫度對(duì)油紙絕緣短時(shí)耐受電壓和失效時(shí)間的影響規(guī)律進(jìn)行了試驗(yàn)研究。采用均勻升壓法，在五個(gè)溫度下測(cè)量了油紙絕緣在脈動(dòng)直流、交流和直流電壓下的短時(shí)耐受電壓，結(jié)合油紙絕緣相對(duì)介電常數(shù)和體積電阻率隨溫度的變化規(guī)律，對(duì)脈動(dòng)直流電壓下油紙絕緣短時(shí)耐受電壓隨溫度變化的規(guī)律進(jìn)行了分析；采用恒壓法，測(cè)量了油紙絕緣在三種電壓下的失效時(shí)間，分析了油紙絕緣失效時(shí)間隨電壓和溫度的變化規(guī)律。測(cè)量結(jié)果表明，與交流和直流電壓相比，脈動(dòng)直流電壓下的油紙絕緣電老化特性具有顯著差異。 ②研究了油紙絕緣在脈動(dòng)直流電壓下電老化過(guò)程中的空間電荷變化特性。采用電聲脈沖法測(cè)量了電老化油紙?jiān)嚻穬?nèi)部空間電荷密度，分析了電老化油紙?jiān)嚻返目臻g電荷注入、累積、積聚和消散過(guò)程，研究了電老化時(shí)間和溫度對(duì)油紙?jiān)嚻房臻g電荷匯聚和消散特性的影響。試驗(yàn)與分析結(jié)果表明，電老化時(shí)間的增加和溫度升高，均會(huì)導(dǎo)致油紙?jiān)嚻穬?nèi)部電荷密度增加，溫度升高使得空間場(chǎng)強(qiáng)畸變更為嚴(yán)重。 ③研究了脈動(dòng)直流電壓下電老化油紙絕緣的空間電荷特征量及其變化規(guī)律，探究了油紙絕緣電老化特性。通過(guò)試品內(nèi)部空間電荷密度，計(jì)算并對(duì)比分析了油紙絕緣空間電荷特征量隨老化時(shí)間和溫度變化的規(guī)律，提出了油紙絕緣空間電荷特征量與電老化特性相結(jié)合的分析方法，探究了老化時(shí)間和溫度對(duì)油紙絕緣電老化特性的影響機(jī)制。研究結(jié)果表明，電老化時(shí)間的延長(zhǎng)加速油紙絕緣老化。溫度的升高增強(qiáng)了電場(chǎng)對(duì)油紙絕緣電老化特性的影響。 ④通過(guò)分析油紙絕緣失效時(shí)間和失效場(chǎng)強(qiáng)威布爾分布的變化規(guī)律，提出了油紙絕緣多風(fēng)險(xiǎn)失效模型的構(gòu)建方法，建立了雙變量威布爾失效模型，分析了脈動(dòng)直流電壓下油紙絕緣電老化失效率的準(zhǔn)確性，提出了油紙絕緣失效率分布的綜合檢驗(yàn)指標(biāo)反映失效模型估計(jì)正確性和精度的評(píng)估方法，驗(yàn)證了雙變量威布爾失效模型的正確性和建模方法的有效性。結(jié)果表明，雙變量威布爾失效模型更有效反映失效場(chǎng)強(qiáng)與油紙絕緣失效率之間的關(guān)系，，提高了失效模型計(jì)算結(jié)果的準(zhǔn)確性。 上述研究工作是在換流變壓器閥側(cè)繞組絕緣的電老化特性方面的積極探索，揭示了在脈動(dòng)直流電壓下老化時(shí)間和溫度對(duì)油紙絕緣電老化的影響機(jī)制。同時(shí)豐富了油紙絕緣電老化評(píng)估的研究成果，并為換流變壓器油紙絕緣失效診斷以及可靠性評(píng)估提供了理論支撐和試驗(yàn)依據(jù)。
[Abstract]:The converter transformer is the key equipment of the HVDC transmission system. Compared with the ordinary power transformer, the operation condition of the converter transformer is more severe and the fault rate of the converter transformer is higher than the ordinary power transformer. In view of the requirement of the reliability evaluation of the oil paper insulation of the converter transformer, the DC voltage tolerance characteristic of the oil paper insulation pulsation is required. The three aspects of the space charge characteristics of oil paper insulation and the failure model of oil paper insulation in the process of electrical aging are studied in depth.
The influence of pulsating DC voltage tolerance of oil paper insulation and the influence of pulse coefficient and temperature on short-time tolerance voltage and failure time of oil paper insulation is studied. The short-time tolerance voltage of oil paper insulation under pulsating DC, AC and direct current voltage is measured at five temperatures by uniform lift method. The relative dielectric constant and volume resistivity of the oil paper insulation under the pulsating DC voltage are analyzed with the change of temperature with the change of temperature. The failure time of oil paper insulation under three voltages is measured by constant pressure method, and the variation of the failure time of oil paper with voltage and temperature is analyzed. The results show that compared with AC and DC voltage, the electrical aging characteristics of oil paper insulation under fluctuating DC voltage are significantly different.
The change characteristics of space charge in the process of electric aging of oil paper insulation under pulsating DC voltage were studied. The internal space charge density of the test products of electric aging oil paper was measured by electroacoustic pulse method. The space charge injection, accumulation, accumulation and elimination of electrical aging oil paper test products were analyzed, and the electrical aging time and temperature were studied on the test products of oil paper. The experimental and analysis results show that the increase of the electrical aging time and the increase of temperature will result in the increase of the internal charge density of the test products of oil paper, and the temperature increase makes the spatial field strength change seriously.
The characteristic quantity of space charge and the change law of electric aging oil paper insulation under pulsating DC voltage are studied, and the electrical aging characteristics of oil paper insulation are explored. Through the internal space charge density of the test products, the characteristics of the space charge characteristics of oil paper insulation with aging time and temperature are calculated and compared, and the insulation space electricity of oil paper insulation is put forward. The influence mechanism of the aging time and temperature on the electrical aging characteristics of oil paper insulation is investigated by the method of combining the load and the electrical aging characteristics. The results show that the prolonging of the aging time accelerates the aging of oil paper insulation. The increase of temperature enhances the effect of the electric field on the aging characteristics of oil paper insulation.
4. By analyzing the failure time of oil paper insulation and the change law of Weibull distribution of the failure field strength, the construction method of the multi risk failure model of oil paper insulation is put forward, the bivariate Weibull failure model is established, the accuracy of the failure rate of the oil paper insulation under pulsating DC voltage is analyzed, and the distribution of the failure rate of oil paper insulation is put forward. The combined test indexes reflect the correctness and accuracy of the failure model, and verify the correctness of the bivariate Weibull failure model and the validity of the modeling method. The results show that the bivariate Weibull failure model is more effective in reflecting the relationship between the failure field strength and the failure rate of the oil paper insulation, and improves the calculation results of the failure model. Accuracy.
The above research work is an active exploration on the electrical aging characteristics of the insulation of the valve side winding of the converter transformer. It reveals the influence mechanism of the aging time and temperature on the insulation aging of the oil paper under the pulsating DC voltage. It also enriches the research results of the evaluation of the insulation aging of the oil paper insulation and diagnoses the oil paper insulation failure of the converter transformer. It provides theoretical support and experimental basis for reliability evaluation.

【學(xué)位授予單位】：重慶大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2014
【分類(lèi)號(hào)】：TM855

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 高敏華,冷勇;換流變壓器中的兩個(gè)直流分量[J];變壓器;2002年06期

2 景崇友;王建民;陳志偉;吳增泊;;換流變壓器繞組瞬態(tài)漏磁場(chǎng)與諧波損耗的分析[J];變壓器;2007年04期

3 王長(zhǎng)勝;王健;湯焱;韓雪梅;;±800kV換流變壓器油流溫升計(jì)算分析[J];變壓器;2009年09期

4 廖瑞金;解兵;楊麗君;梁帥偉;程渙超;孫才新;向彬;;油紙絕緣電-熱聯(lián)合老化壽命模型的比較與分析[J];電工技術(shù)學(xué)報(bào);2006年02期

5 周遠(yuǎn)翔;王寧華;王云杉;孫清華;梁曦東;關(guān)志成;;固體電介質(zhì)空間電荷研究進(jìn)展[J];電工技術(shù)學(xué)報(bào);2008年09期

6 司文榮;李軍浩;袁鵬;郭弘;羅勇芬;李彥明;;直流下局部放電序列信號(hào)檢測(cè)與特性分析[J];電工技術(shù)學(xué)報(bào);2010年03期

7 周遠(yuǎn)翔;孫清華;李光范;王云杉;姜鑫鑫;仇宇舟;李金忠;王寧華;;空間電荷對(duì)油紙絕緣擊穿和沿面閃絡(luò)的影響[J];電工技術(shù)學(xué)報(bào);2011年02期

8 李博;程渙超;孫倩;李金忠;李光范;鄧俊宇;樊煒;徐會(huì)雨;;交直流電壓分量對(duì)變壓器油中典型模型擊穿特性影響[J];電工技術(shù)學(xué)報(bào);2011年02期

9 廖瑞金;楊麗君;鄭含博;汪可;馬志欽;;電力變壓器油紙絕緣熱老化研究綜述[J];電工技術(shù)學(xué)報(bào);2012年05期

10 李季;羅隆福;許加柱;李勇;姚遠(yuǎn);;換流變壓器閥側(cè)絕緣電場(chǎng)特性研究[J];高電壓技術(shù);2006年09期

相關(guān)博士學(xué)位論文 前5條

1 楊麗君;變壓器油紙絕緣老化特征量與壽命評(píng)估方法研究[D];重慶大學(xué);2009年

2 唐超;油紙絕緣介質(zhì)的直流空間電荷特性研究[D];重慶大學(xué);2010年

3 許中榮;變壓器繞組固體絕緣中微氣泡放電機(jī)理與壽命分析[D];重慶大學(xué);2010年

4 劉剛;換流變壓器交直流復(fù)合電場(chǎng)和極性反轉(zhuǎn)電場(chǎng)算法研究[D];華北電力大學(xué);2012年

5 郝建;變壓器油紙絕緣熱老化的時(shí)頻域介電和空間電荷特性研究[D];重慶大學(xué);2012年

本文編號(hào)：1826011