Flux and loss distribution in a split-core five-limb transformer

The results of an experimental investigation of the flux distribution and power loss in scale models of five-limb transformer cores with split and nonsplit inner limbs are presented. It is found that there is no significant difference in the fundamental flux pattern of the two types of core. However, a variation of 115% in the instantaneous third-harmonic component of in-plane flux between the two has been noticed. The normal flux is dominant in the overlap areas of the T-joints and the inner limbs of the split core and more so in the overlap areas of the outer and central T-joints of the nonsplit core. There is little difference in localized losses between the cores; however, the loss in the outer T-section of the nonsplit core is marginally lower in magnitude than that of the split core