【正文】
day the failures are reported on paper sheets and saved in paper form at Eker246。 grid was made. The statistics reported to Darwin, Eker246。 Energi has avoided breakdowns by water tree deteriorated cables could have been that they have used a lot of sand when placing the cables in the ground. It is difficult to say if the measurements made in 1998 were trustworthy or not. What could be said on the other hand, is that even though three of them were judged as old and four of them judged as critical for nine years ago they are all still operating. The mercial cable diagnostic instrument for XLPEcables available on the market right 5 now are all offline instruments. All instruments except one measure the dissipation factor tanδ , at either a fixed low frequency or at a low frequency sweep or at powerline frequency. The other technique used, is to measure the isothermal relaxation current. The techniques used in these instruments are considered to be nondestructive for a voltage level up to 0 U . All fault location instruments in this report are based on time domain reflectometry, TDR. The prelocation are made with two different methods, Time Domain Reflectometry TDR and Arc Reflection Method ARM. The Arc Reflection Method is used to prelocate high resistance fault and the Time Domain Reflectometry is used to prelocate low resistance faults. The instruments are suited for low and medium voltage distribution cables. The statistic from the Stockholm grid shows that the major number of faults is connected to underground cables. The largest fault category for high voltage, low voltage and service cables are the category lack of maintenance or worn out cables. The second large category for all three voltage levels is the category unknown. The largest damages on the high voltage system caused by failures in these two categories are connected to the XLPEcables. However, reading the statistic it is not possible to say if the XLPEcable failures are connected to insulation problems or something else. The fault frequency in Stockholm’s XLPEcables was 3,34 in 2020 and 3,76 in 2020 faults per 100 km cable and year. The total fault frequency in Stockholm was 3,55, which is in the same size as the total fault frequency in G246。如果有 什么 診斷測(cè)量應(yīng)該會(huì) 需要 這些信息。該報(bào)告的質(zhì)量是非常 依賴于 報(bào)道家 。 是 Energi 內(nèi)部說(shuō)明。的故障頻率 看起來(lái)有點(diǎn)低 。 是 Energi自己的統(tǒng)計(jì)數(shù)據(jù)以及該故障報(bào)告調(diào)查 是根據(jù)統(tǒng)計(jì)得到的 。 PFL401500/2020 是 Megger 所提供的,是一 電池供電的便攜式儀器。通用電氣的國(guó)際開(kāi)發(fā)協(xié)會(huì) 200 HVU, 現(xiàn)在 由 Pax diagnost 和 所謂 Idax 206 VAX 230 生產(chǎn)和銷售 的產(chǎn)品能夠測(cè)量 赫茲之間 的 變頻波 耗散及 介損 系數(shù)。電容并不顯示任何電壓 依賴。該電纜不顯示任何電壓依賴和滯后 的 3 反應(yīng)。 第二組的電纜是從 80年代初 開(kāi)始使用的 1號(hào) 電纜和 4號(hào) 。該 電纜將繼續(xù) 使用 多年。 所測(cè)電纜可分為四 組 。其次,高電場(chǎng)的存在,這意味著,這一現(xiàn)象只發(fā)生在高壓電纜 中 。 時(shí)之間變化。 的交聯(lián)聚乙烯電纜電網(wǎng) 中, 總故障的頻率是每 100 公里 1,99斷層線,可與 達(dá)爾文 的故障頻報(bào)相比, 電纜故障 是 每 100公里 2,41公里 。 Energi的網(wǎng)格統(tǒng)計(jì)方法更廣泛。對(duì)于高電壓,低電壓 的 服務(wù) 是 最大故障類別 , 但 電纜的維修或磨損 類別 卻很少 。除了一個(gè)損耗因數(shù) tanδ 的測(cè)量在任一固定低頻率或低頻率掃描或電源線頻率 以外 。其中 至少有一個(gè)是電纜 周圍 的粘土 對(duì)電纜的壓迫造成 的損害。在報(bào)告中,在不同情況使用不同的技術(shù)手段 。 經(jīng)常出現(xiàn)的故障 是 暫態(tài)過(guò)電壓 的 情況 , 例如當(dāng)電纜重新連接后,它已退出服務(wù)電纜。 1 中壓電纜網(wǎng)絡(luò)絕緣診斷和故障統(tǒng)計(jì) 的狀態(tài)評(píng)估 戈蘭 Semart 在當(dāng)今的 電氣社會(huì) ,電力公司是 作為 一個(gè) 分銷商 是很 重要的 ,特別是在 象 瑞 典 這 樣的 非規(guī)范的市場(chǎng) 。導(dǎo)致這種現(xiàn)象在年底 檢測(cè) 到電纜故障。此概述可提供商業(yè)診斷 信息 ,以及他們使用哪種技術(shù)。 Energi 只 多了 三個(gè)相關(guān)的電纜絕緣 故障。 對(duì)于 商業(yè)電纜交聯(lián)聚乙烯,電纜市場(chǎng)上現(xiàn)有的診斷工具,現(xiàn)在都 是 離線工具。 來(lái)自斯德哥爾摩的統(tǒng)計(jì)表明,電網(wǎng)故障的主設(shè)備 是相連的地下電纜。 Eker246。在Eker246。 當(dāng)今世界 電力 是 社會(huì) 良好運(yùn)作的關(guān)鍵 保障 ,在瑞典的最后十年消費(fèi)量 在 143150 億千瓦 首先,保護(hù)周圍的土壤,如粘土電纜 和 水。 在他們的實(shí)驗(yàn)中,通過(guò)檢測(cè)電纜狀況來(lái)進(jìn)行評(píng)估。然而,電容圖顯示無(wú)電壓依賴性,這表明該電纜狀況良好。該電纜將繼續(xù) 使用 很多年。 第三組是從 80 年代中期 開(kāi)始使用的 7號(hào)電纜線。該電纜顯示了一個(gè) 與 電壓無(wú)關(guān)的漏電 , 沒(méi)有磁滯電流響應(yīng)。在文書中使用的技術(shù)各不相同。 SebaKMT 提供了四個(gè)文書 Surgeflex 15, 25, 32,泰利福 T 30E, Surgeflex 15, 25和泰利福 T 30E是電池供電和便攜 式儀器。該 統(tǒng)計(jì)報(bào)告 說(shuō)明, 電纜 Eker246。然而, 由于 挖掘,客戶故障, 以及 在車站 5次洪水造成 17故障 , Eker246。 更可 靠的故障信息在 Eker246。 是 Energi那里得到的紙質(zhì)報(bào)告是失敗的 。還應(yīng)該有關(guān)于失敗的原因和影響的信息。, due to that the soil consists of sand and gravel that has a draining quality. Another reason that Eker246。 grid shows that there is a need of more categories inserted in the report system. The aim with inserting more categories is to refine the statistic in order to get a more exact evaluation of what causes the interruptions. This evaluation can then be used to direct the measure right, improve the failure statistic and reduce the interruptions. Today is the demand of electrical power crucial for a well functioning society,the consumption in Sweden the last ten years has varied between 143150 TWh. The last years problems with blown down overhead lines and power cuts caused by storms, has hasten the replacement of overhead lines in favour of underground cables. It has be