Normal direction of flux distribution in the mix 60° - 23° T-joint of three phase transformer core

This paper describes the result of measurement of normal flux distribution 3-phase 100kVA transformer core assembled with the mix 60° - 23° in different layers of T-joint. The investigation involves the variation of normal flux distribution in the core lamination. The normal flux distribution has been measured using no load test by arrays of search coil. The highest normal flux distribution occurs at the corner edge of the centre limb that is 0.17T and lowest at upper edge of yoke that is 0.09T. The average value of normal flux distribution is high at flux transfer region of the lamination. The flux transfer mechanism shows that two separate path flowing horizontally in the yoke before leaving the lamination to vertically adjacent layer and combine with the flux in that layer. Then, it will transfer back to origin region and extend through the centre limb.