Simulation of Flux Distribution and Loss Calculation at Three-Phase Three Limbs of Transformer Core with 23 T-Joint

Abstract

This paper describes the result of simulation of flux distribution on 100kVA 3phase distribution transformer assembled with 23 T joint and mitred lap corner joint with stagger yoke and limb for one lamination. The simulation involves the variation of flux. The flux distribution have been simulated using 2DFEM by Quick field Software built from M5 (CGO) grades material of transformer core laminations. The flux density is 1.78 T maximum at the center limb of transformer core and the loss calculation is 1.274 W/kg. This paper describes the result of measurement of localized loss distribution on 100KVA 3phase distribution transformer assembled with 23 Tjoint and mired lap corner joint with staggered yoke. The measurement involves the variation of temperature rise. The localized loss have been measured using no load test by arrays of thermistor on the surface of MN5 (CGO) grades material of material of transformer core laminations. The localised loss at the outer 23 T joint is 1.05 W/kg and rises to be 1.26 W/kg at the inner 23 T-joint when the transformer core energized 1.5 T 50Hz. The several harmful effects can occur because the flux flows out of the rolling direction.