The Influence of Core Material Grade on Flux Distortion in Three-limb Transformer Core

The influence of material grade on localized flux distribution and harmonics level has been investigated on scale models of three-limb core made from three different core materials (M4, M0H and ZDKH grades). In relation to the model from the conventional M4 grade material, both models from higher grade materials (M0H and ZDKH) have higher flux distortion. The increase of power loss due to flux distortion has been calculated, and the results are in good agreement with the known differences in building factors of cores with higher and conventional grade materials.