Aging and Life Assessment of Large and Medium-sized Power Transformers in Nuclear Power Plants

In order to effectively manage the large and medium-sized power transformer in nuclear power plants, several methods for the aging and life assessment of large and medium-sized power transformers used in nuclear power plants are analyzed and described, including the thermal aging life assessment method of transformer solid insulation, the thermal aging life assessment method considering the moisture content of the insulation paper, the aging and life assessment analysis method based on the average degree of polymerization of the insulation paper and the furfural content of the insulation oil. The aging and life assessment for six single-phase main transformers of a nuclear power plant has been implemented through the combined use of these methods and some satisfactory results have been got. The integrated use of these assessment methods elaborated in this paper can contribute to a more reasonable and accurate assessment of the overall life of transformers, and provide a reasonable and important reference for the aging and life cycle management for large and medium-sized power transformers in nuclear power plants.