OVERLOADING AND LOSS-OF-LIFE ASSESSMENT GUIDELINES OF OIL-COOLED TRANSFORMERS: A COMPARISON OF THE IEEE AND IEC STANDARDS

摘要

Estimation of a power transformer's remaining life is of concern to most owners, especially when the transformer is known to have been overloaded either continuously or intermittently over long periods. To make economical decisions regarding replacement, it is critical to know how long a transformer is expected to last. This article discusses the insulation aging and life expectancy estimation of oil-filled transformers, and provides a direct comparison of IEEE Std. No. C57.91-1995 and IEC Std. No. 354-1991. This work also provides simplified transformer overloading guidelines.