Optimization and analysis of tapping position on leakage reactance of a two winding transformer

Abstract

To ensure a reliable and stable power supply, optimal design and proper installation of the transformer are essential for the power suppliers and distributors. Short-circuit current is the main parameter of the transformer and causes the failure in the transformers. Accurate calculation and optimization of the leakage reactance help the transformer designers to mitigate against failure during the short circuit conditions. Transformer designers use different tapping positions for the manufacturing of the two-winding tap transformers. This study analysis and optimizes the leakage reactance of the two-winding tap transformer. Leakage reactance behavioral characteristics of the six different tappings are evaluated and examined in this study, including (1) without tapping, (2) upper tapping, (3) lower tapping, (4) middle tapping, (5) lower–upper tapping, (6) side tapping of the low voltage winding using finite element method. The results show that the side tapping has the least impact on the leakage reactance. The results also show that upper tapping and lower tapping have a significant effect on the leakage reactance. The comparison between the finite element method and experimental short-circuit test results for the optimized design also suggests that the finite element models can accurately evaluate the leakage reactance in the two-winding tap transformers.