Advancements in the Industry: Determining Cellulose Degradation in Transformers Using Indirect Tests

Lance R. Lewand and David Koehler, Doble Engineering Company Fall 2021 CAP Corner, CAP Corner

The design life of a transformer is usually about 20 to 25 years. In the United States, estimates show the average age of a transformer is currently around 42 years, which means a number of even older units are still in service. As with all things, transformers age and degrade over time. Transformer failures can come from a variety of …