本文選題：XLPE電纜 + 老化狀態(tài)��； 參考：《華南理工大學(xué)》2016年碩士論文

【摘要】：在探討XLPE電纜老化機(jī)理的基礎(chǔ)上,從理、化、電3個(gè)角度對(duì)運(yùn)行電纜樣品的壽命進(jìn)行評(píng)估。對(duì)110kV XLPE電力電纜的老化狀態(tài)及剩余壽命的研究分為兩個(gè)階段。第一階段為電力電纜的理、化、電特性老化試驗(yàn),第二階段為電力電纜絕緣層的理、化特性老化試驗(yàn)。第一階段的試驗(yàn)包括局部放電試驗(yàn)、逐級(jí)耐壓試驗(yàn)、等溫松弛電流試驗(yàn)、熱老化試驗(yàn)、熱失重分析實(shí)驗(yàn)、差示掃描量熱法試驗(yàn)。局部放電試驗(yàn)結(jié)果表明,這6個(gè)電纜樣品狀態(tài)仍然符合國(guó)家標(biāo)準(zhǔn)可以進(jìn)行后續(xù)的理、化、電特性試驗(yàn)。逐級(jí)耐壓試驗(yàn)結(jié)果表明,運(yùn)行電纜的剩余壽命為10~30年,備用電纜的剩余壽命為30~50年。等溫松弛電流試驗(yàn)結(jié)果表明,由老化因子得到的結(jié)果只是一種趨勢(shì)性的判斷。經(jīng)電熱老化處理后,電纜的老化因子增大。熱老化試驗(yàn)結(jié)果表明,電纜線芯溫度介于80~90℃之間時(shí),這些電纜的剩余壽命在10~25年之間。熱失重試驗(yàn)結(jié)果表明,熱老化后,4個(gè)樣品活化能下降,2個(gè)樣品活化能上升;材料體系的相互配合、抗氧化劑的使用及工藝會(huì)影響電纜的質(zhì)量。電熱老化試驗(yàn)老化后,5個(gè)樣品的氧化誘導(dǎo)期明顯降低,1個(gè)樣品升高。說(shuō)明老化后,氧化誘導(dǎo)期趨于明顯降低。第二階段絕緣層的理、化試驗(yàn)包括PEA、TGA、FTIR、X-ray試驗(yàn)。PEA、TG、FTIR微觀試驗(yàn)結(jié)果表明,與中層相比,內(nèi)層空間電荷積累量增多14.86%,活化能下降3.68%,羰基指數(shù)增大5.57%,亞甲基指數(shù)下降66.78%,內(nèi)、外層老化更嚴(yán)重。X-ray實(shí)驗(yàn)結(jié)果表明電纜絕緣層中存在發(fā)生形變的球晶。運(yùn)行初期,在無(wú)氧條件下以聚乙烯分子交聯(lián)反應(yīng)占主導(dǎo),促進(jìn)分子結(jié)構(gòu)完善;運(yùn)行后期,在有氧條件下以氧化降解反應(yīng)占主導(dǎo),加速絕緣材料老化。通過(guò)空間電荷積累量、活化能以及羰基指數(shù)的變化能合理解釋內(nèi)、中、外層的老化規(guī)律。
[Abstract]:On the basis of discussing the aging mechanism of XLPE cables, the life of running cable samples was evaluated from three aspects: mechanism, chemistry and electricity. The study on the aging state and residual life of 110kV XLPE power cable is divided into two stages. The first stage is the aging test of power cable insulation layer, the second stage is the aging test of power cable insulation layer. The first stage of the test includes partial discharge test, step by step voltage test, isothermal relaxation current test, thermal aging test, thermogravimetric analysis test, differential scanning calorimetry test. The results of partial discharge test show that the state of the six cable samples is still in accordance with the national standard. The results show that the residual life of the running cable is 10 ~ 30 years and the remaining life of the spare cable is 30 ~ 50 years. The results of isothermal relaxation current test show that the results obtained from aging factor are only a trend judgment. After electrothermal aging, the ageing factor of cable increases. The results of thermal aging test show that when the cable core temperature is between 80 鈩，

本文編號(hào)：1792999