2007年6月13日，ABB宣布，一項服務技術可將變壓器的使用壽命延長至25年，使用烘干處理技術，完成這一處理不用移動設備，在4-5天就可以完成。 　　變壓器是其中最簡單的電氣設備，并擁有全部型號——從一個微小的內置擴音器的耦合變壓器，到一個80噸的相移設備，由此調整著國家電網的功率流量。 　　無論大或是小，他們在電子系統中是非常重要的元件，由于他們可將交流電流變成高電壓或是低電壓的能力，因此其可以被有效地傳輸和用戶的安全使用。 　　問題在于，存在于許多變壓器內部的紙和礦物油隨著時間在退化。形成的水和酸之類的殘渣在變壓器內部聚積，最終使其變壞。 　　沒有正確的絕緣體，變壓器將逐漸遺失其能力，不能夠再阻擋每天操作帶來的損害和緊迫的短路事件。 　　客戶滿意度 但是ABB擁有一個新方法，與低頻加熱和油過濾相結合，用于保護絕緣體，最終實現保護變壓器。 沒有烘干前紙的含水量為2.5％。烘干后其含水量為1.0％，可與剛出廠的新變壓器做比較。 　　當這一方法用于烘干兩個69公噸，200-MVA，300/125/17 kV Nett變壓器時，每一個變壓器的使用壽命延長了10到15年，對于設備來說節省效果非常顯著。 　　現場工作中，對于用戶另一種顯著的節省的辦法————從變壓器里萃取出了70升水。在操作前，絕緣變壓器油可回收油，油箱，箱蓋也都是可回收元件，生銹后可以再打磨光。所有事可在很短的時間內完成。 　　低頻熱脈沖 在過去，從變壓器中把水萃取出來要對變壓器油進行反復的過濾才行。 　　由于許多水不在變壓器油中，而存在于變壓器里積極的部分，要想把這些水清除掉要花費好幾周。 　　ABB完美的低頻熱烘干法，通過利用電脈沖加熱變壓器鐵芯，使水蒸發出來，有效地將水與油隔離，這樣可以快速安全地過濾出來。 　　這種方法操作起來很快，足以在正常的維護時間內完成，對于許多用戶來說極其的重要，如器械需要很短的停工時間。 　　低頻脈沖對于加熱變壓器核心設備，叫繞組，保證更多的溫度保持統一。在現場烘干變壓器時，因為高溫會損壞熱感應區域，所一致性尤其的重要。 　　ABB還利用雙重加熱系統，無論高壓或低壓繞阻根據他們的變化程度施以不同的溫度。 　　這就使得ABB的烘干技術在任何危險中都可以使用高溫烘干方法。 original text [COLOR=#708090]Drying technology breathes new life into old transformers 2007-06-13 - ABB service technology can extend a transformer‘s lifetime by up to 25 years, using a drying process that can finish the job in four or five days without moving the unit. Transformers are among the simplest electrical devices, and they come in all sizes – from a tiny coupling transformer inside a microphone, to an 800-ton phase-shifting unit that regulates power flow in national power grids. Big or small, they are vital components in electrical systems because of their ability to convert alternating current into higher and lower voltages, so that it can be transported efficiently and used by consumers safely. The problem is that the paper and mineral oil insulating the interior of many transformers degrades over time. This leaves a residue of water and acid that begins to accumulate inside the transformer, and eventually accelerates its breakdown. Without proper insulation, a transformer gradually loses its ability to withstand the rigor of daily operations and stressful events like short circuits. Satisfied customer But ABB has a new drying method that combines low frequency heating and oil filtration to save the insulation, and ultimately, the transformer. When this method was used to dry two, 69-tonne, 200-MVA, 300/125/17 kV Nett transformers for the Norse utility Lyse Energi, each transformer‘s lifecycle was extended by 10 to 15 years, a significant savings for the utility. Working on site – another significant savings to the customer – ABB extracted 70 liters of water from one of the transformers. Before processing, moisture content of the insulation paper was 2.5 percent. After drying it was 1.0 percent, comparable to the specs of a new transformer straight out of the factory. Transformer oil was reclaimed and the tank and cover, refurbished due to rust. Everything took place in the field with minimal disruption. Low-frequency heat pulse In the past, removing water from a transformer involved filtering the transformer oil repeatedly. Since most of the water is not in the transformer oil but in the active part of the transformer, removing water in this way could take several weeks. ABB perfected a low-frequency heat drying method that heats the transformer core with an electrical pulse, creating a vapor action that effectively pushes moisture from the insulation into the oil, where it can be quickly and safely filtered out. It is fast enough to be completed within a regular maintenance shutdown, which is extremely important for many customers – like utilities – who demand minimal downtime. Low-frequency pulses are also safer for heating transformer conductors, called windings, and ensure a more uniform temperature. Uniformity is especially important when drying large transformers on-site, because higher temperatures risk damaging heat-sensitive areas. ABB also uses a dual heating system, in which the high- and low-voltage windings can be set to different temperatures according to their varying heat tolerances. This allows ABB to use a higher drying temperature without placing the transformer at any risk.[/COLOR]