A Condition Assessment Model of Oil-immersed Transformers Using Cloud and Matter Element Integrated Method

High voltage oil-immersed transformers are the most important components in the power system. If there is a potential fault in the transformer it may cause a power failure even a catastrophe. Therefore, it is important to assess the condition of the transformer accurately and to make some relative maintenance to minimize the risk of premature failure. However, condition assessment of transformers can be considered as a multiple-attribute decision-making (MADM) problem which is full of uncertain, fuzzy and randomness information. Aiming at this intricate problem, this paper presents a cloud and matter element integrated approach for assessing the condition of transformers. An assessing index system is established, which includes dissolved gas analysis (DGA), electrical testing and oil testing. An integrated model based on matter element approach and cloud approach is applied to assess the condition of the transformer. Cases study show that the proposed approach is practical and effective. The assessing result can be regarded as a useful suggestion to condition based maintenance of high voltage oil-immersed transformers. Streszczenie. W artykule przedstawiono metode oceny stanu technicznego transformatora olejowego, opartą na analizie elementow chmury oraz tzw. Matter-Element Analysis. Opracowany zostal zintegrowany model oraz wskaźnik szacujący stan transformatora, uwzgledniający czynniki takie jak: analiza rozpuszczonych gazow (DGA), testy elektryczne i olejowe. Przeprowadzone badania potwierdzily skutecznośc metody. (Ocena stanu technicznego transformatora olejowego na podstawie modelu szacunkowego - wykorzystanie metod elementow chmury i materii).

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