Operating partial core transformers under liquid nitrogen conditions

A reverse design method has been applied to partial core transformers. Three sample transformers were built and then tested under liquid nitrogen (N₂) conditions. The measured results were compared to model calculated values and the differences used to modify the reverse design model in order to more accurately determine the calculated equivalent circuit parameters. A fourth transformer was then designed, built and tested. The measured performance of this transformer confirmed the validity and accuracy of the model, and showed the usefulness of the reverse design approach