接地線的接地方式的基本組成
一般在光伏電站中,接地引下線和接地體的電阻很小,多可忽略。系統(tǒng)的接地電阻主要為接地體到大地?zé)o限遠(yuǎn)處的電阻,即主要由接地體周?chē)耐寥离娮杪蕸Q定。 土壤電阻率
高壓接地線分類(lèi):(1)高壓接地線按照使用環(huán)境可以分為:室內(nèi)母排型接地線(JDX-NL)和室外線路型接地線(JDX-WS)。 (2)高壓接地線按照電壓等級(jí)可分為:10KV接地線,35KV高壓接地線,110KV接地線,220KV高壓接地線,500KV高壓接地線
核實(shí)接地棒的電壓等級(jí)與操作設(shè)備的電壓等級(jí)是否一致。
使用攜帶型短路接地線前,應(yīng)先驗(yàn)電確認(rèn)已停電,在設(shè)備上確認(rèn)無(wú)電壓后進(jìn)行。先將接地線夾連接在接地網(wǎng)或扁鐵件上,然后用接地操作棒分別將導(dǎo)線端線類(lèi)擰緊在設(shè)備導(dǎo)線上。拆除短路接地線時(shí),順序正好與上述相反。
光伏電站接地系統(tǒng)敷設(shè)常會(huì)面臨下列三項(xiàng)問(wèn)題: a.選擇主控室和各逆變器室位置 主控室和逆變器室應(yīng)盡量選擇在電阻率減低的土壤周?chē)?。但光伏電站各電氣室受空間限制較大,亦可將接地體敷設(shè)在電阻率較低的土壤里。 b.使用化學(xué)降阻劑 化學(xué)降阻劑一般為高分子合成樹(shù)脂和電解水溶液并混合固化劑而成。將其注入接地體周?chē)髸?huì)變成固液混合形態(tài),大大降低該處電阻率。主要應(yīng)用于高寒和土壤電阻率較高地區(qū)。 c.接地體防腐 根據(jù)廠區(qū)土壤情況合理選擇接地體材質(zhì),保質(zhì)刷涂防腐漆,必要時(shí)可采取陰極保護(hù)。
根據(jù)中性線與保護(hù)線是否合并的情況,TN系統(tǒng)又分為T(mén)N-C、TN-S及TN-C-S系統(tǒng)。 TN-C系統(tǒng):保護(hù)線與中性線合并為PEN線。 TN-S系統(tǒng):保護(hù)線與中性線分開(kāi)。 TN-C-S系統(tǒng):在靠近電源側(cè)一段的保護(hù)線和中性線合并為PEN線,從某點(diǎn)以后分為保護(hù)線和中性線。
eing conducted with the Emperor, and yet, said Norfolk, no sooner was the imperial ambassador gone than Leicester pushed his own courtship more strongly than ever. He was told plainly that if he did not desist evil would befall him, as all the nobility were against him; whereupon Leicester went off in a huff and sulked for a fortnight, until the Queen recalled him and petted him more than ever, upon which Norfolk in turn took umbrage and went home, leing the Archduke’s interests in the hands of Sus. For months this game of cross pures went on. One afternoon in February, 1566, Guzman saw the Queen walking with Leicester in the lower gallery overlooking the gardens of Whitehall. In conversation with the ambassador she praised her fourite to his face, and said that he was just trying to persuade her to marry, for the sake of herself, the country, and even on his (Leicester’s) account, as
現(xiàn)場(chǎng)工作不得少掛接地線或者擅自變更掛接地線地點(diǎn)。
在自動(dòng)化科技飛速發(fā)展的今天,光伏電站已進(jìn)入“無(wú)人值班,少人值守”的運(yùn)行模式。接地系統(tǒng)的完善,作為保護(hù)設(shè)備、人身安全的重要保障,理應(yīng)得到大家的重視。光伏電站的接地系統(tǒng),除了應(yīng)遵守國(guó)家有關(guān)規(guī)程、保證施工質(zhì)量外,還要因地制宜,根據(jù)現(xiàn)場(chǎng)實(shí)際情況,分析工程特點(diǎn),多對(duì)周邊在運(yùn)行項(xiàng)目進(jìn)行調(diào)研學(xué)習(xí),確保安全生產(chǎn)。
現(xiàn)今,隨著光伏發(fā)電技術(shù)的日趨成熟和大量已建成光伏電站的運(yùn)營(yíng),系統(tǒng)安全性已經(jīng)成為了保障日常生產(chǎn)的重要因素。以往許多人們對(duì)于“小容量”光伏電站的接地、防雷問(wèn)題并不重視,但隨著太陽(yáng)能電池板功率和電站系統(tǒng)容量的增大,近年來(lái)由于接地不良造成的人身觸電傷亡事件已為數(shù)不少。本文將列舉在建設(shè)過(guò)程中可能會(huì)遇到的接地施工問(wèn)題并淺析接地技術(shù)。
光伏電站接地系統(tǒng)敷設(shè)常會(huì)面臨下列三項(xiàng)問(wèn)題: a.選擇主控室和各逆變器室位置 主控室和逆變器室應(yīng)盡量選擇在電阻率減低的土壤周?chē)?。但光伏電站各電氣室受空間限制較大,亦可將接地體敷設(shè)在電阻率較低的土壤里。 b.使用化學(xué)降阻劑 化學(xué)降阻劑一般為高分子合成樹(shù)脂和電解水溶液并混合固化劑而成。將其注入接地體周?chē)髸?huì)變成固液混合形態(tài),大大降低該處電阻率。主要應(yīng)用于高寒和土壤電阻率較高地區(qū)。 c.接地體防腐 根據(jù)廠區(qū)土壤情況合理選擇接地體材質(zhì),保質(zhì)刷涂防腐漆,必要時(shí)可采取陰極保護(hù)。
Spanish interests, “as the common people are so full of projects for marrying Madam Elizabeth to the Earl of Arundel or some one else.” On the 8th of November a committee of the Council went to Hatfield to see Elizabeth and deliver to her the dying Queen’s message, begging her “when she should be Queen to maintain the Catholic Church and pay her (Mary’s) des.” Elizabeth would pledge herself to nothing. She knew now that she must succeed, with or without Mary’s good-will, and she meant to he a free hand. Before the Queen d even, Feria, who had arrived when she was already almost unconscious, hastened to Hatfield to see the coming Queen. So long as he confined himself to courteous commonplace she answered him in the same spirit, but as
接地線、短路接地線使用說(shuō)明以及維護(hù)一、接地,接地短路包括: 由短路接地絕緣操作桿、線夾、短路線、接地端子、結(jié)夾、接地夾等?!《?、接地短路接地部分功能:(1)線夾、接地夾采用優(yōu)質(zhì)鋁合金壓鑄、高強(qiáng)度。(2)操作桿與進(jìn)口環(huán)氧樹(shù)脂精制成彩色管,絕緣性能好,強(qiáng)度高,重量輕,顏色明亮,光滑的外觀。分類(lèi)的短路接地包括: (1)分相接地,結(jié)合型線?!?2)使用不同的電壓,單節(jié)式、多型操作?!?3)一個(gè)變電站、線路短路接地。
現(xiàn)今,隨著光伏發(fā)電技術(shù)的日趨成熟和大量已建成光伏電站的運(yùn)營(yíng),系統(tǒng)安全性已經(jīng)成為了保障日常生產(chǎn)的重要因素。以往許多人們對(duì)于“小容量”光伏電站的接地、防雷問(wèn)題并不重視,但隨著太陽(yáng)能電池板功率和電站系統(tǒng)容量的增大,近年來(lái)由于接地不良造成的人身觸電傷亡事件已為數(shù)不少。本文將列舉在建設(shè)過(guò)程中可能會(huì)遇到的接地施工問(wèn)題并淺析接地技術(shù)。