Thesis describes the design and mode of operation of an instrument that measures magnetic imbalance of converter transformer. The so called »magnetic ear« is designed as a magnetic shunt, that is without any influence for the main core.
A part of the main magnetic flux is passed through the instrument and by which this flux changes the inductance of the excitation winding of the magnetic ear.
First part of the thesis focuses on revision of currently used principles of imbalance detection and in extreme cases even saturation of the transformer cores, as well as prevention. Presently saturation detection and prevention techniques are predominantly invasive, they introduce some unwanted features (e.g. air gap) or they are difficult to assemble. Introduction, the theoretical part, is followed by an examination of the test model design and its working principles. There are also examined some improvements of the test model, the ones that reduce the impact of the excitation's magnetic flux. These improvements are put to test by series of examinations.
In the final part, this thesis provides experiences obtained during its making.