In-plane Flux Distribution in 45 T-joint of 3Phase Transformer Core with Staggered Yoke and Limb 10mm

Abstract

This paper describes the result of measurement of in- plane flux distribution on 100KVA 3phase distribution transformer assembled with 45 T-joint and mitred lap comer joint with stagger yoke and limb with overlap length of 10mm. The measurement involves the fundamental and third harmonic of the easy and hard direction of flux density at each location measurement. The flux distributions have been measured using no load test by arrays of search coil in M5 (CGO) grades material of transformer core laminations. The localised flux density at the outer 45 T-joint is 0.218T and rises to be 0.228T at the inner edges of 45 T-joint when the transformer core energized 1.5 T 50Hz. Harmonic occurs mostly in the T-joint where local regions are saturated and the flux deviates from the rolling direction. A small amount of flux deviation from the rolling direction occurs at the overlap, but no rotational flux is present in the joint. This paper describes the result of measurement of in plane flux distribution on 100kKVA 3phase distribution transformer assembled with 45 T-joint and mitred lap corer joint with stagger yoke and limb with overlap length of 10mm. The measurement involves the fundamental and ‘third harmonic of the easy and hard direction of flux density at each location measurement. The flux distributions have been measured using AO load test by arrays of Search coil In MS (CGO) grades material of transformer core laminations. The localised flux density at the outer 45 T-joint is 0.218T and rises to be 0.228T at the Inner edges of 45 T-joint when the transformer core energized 1.5 T S50Hz. Harmonic occurs mostly in the T-joint where local regions are saturated and the flux deviates from the rolling direction. A small amount of flux deviation from ‘the rolling direction occurs at the overlap, but no rotational flux is present in the joint.