Contents
The application of the originally developed thermal model, intended to oil power transformers analyses, is presented in the paper. The model delivers the value of the insulation Hot-spot temperature, as the most critical quantity during transformer loading, and the value of the thermal ageing, both for variable load and variable ambient temperature. The results obtained using the original thermal model are compared with the experimental results and the results obtained by the model from the international standard IEC 354. A program is developed for this purpose, allowing some additional analysis in respect to the basic algorithm from IEC 354.
Besides, using experimentally obtained results, some approximations of the thermal model from IEC 354 and some factors important for development of thermal models are also analyzed.
Übersicht
Das Thema dieses Beitrages ist die Anwendung eines von uns neuentwickelten thermischen Modells zur Analyse von Öltransformatoren. Das Modell liefert den Temperaturwert der Isolation an der heißesten Stelle, welches während der Belastung des Transformators der kritischste Wert ist, sowie die Werte der thermischen Alterung des Transformators, beides unter veränderlicher Belastung und Umgebungstemperatur. Die Ergebnisse unseres Modells werden mit Experimentaluntersuchungen und mit den Resultaten des Modells IEC Standard 354 verglichen. Dafür wurde ein Rechenprogramm ausgearbeitet, das größere Möglichkeiten zur Analyse als das Grundmodell Standard 354 hat.
Schließlich werden einige Vereinfachungen für das IEC-Modell vorgeschlagen und wichtige Faktoren, die während der thermischen Modellentwicklungen auftreten analysiert.
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Radaković, Z., Kalić, D. Results of a novel algorithm for the calculation of the characteristic temperatures in power oil transformers. Electrical Engineering 80, 205–214 (1997). https://doi.org/10.1007/BF01235716
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DOI: https://doi.org/10.1007/BF01235716