Characteristic Evaluation of a Small Cloth Transformer by Considering Flux Density Distribution

This paper describes evaluation of the characteristics of a small cloth transformer by considering the magnetic flux density distribution. We measured the flux density distribution in the magnetic core of a cloth transformer. Using the results, we calculated the coupling factors and ratios of the secondary to the primary voltage for cloth transformers under no load and with various types of winding, and compared the results with measurements. It was found that there is an optimum cloth transformer winding position which maximizes the coupling factor and the ratio of the secondary to the primary voltage under no-load conditions.