Identification of winding faults in electric machines using a high frequency method

High frequency measurements are used more and more frequently as a diagnostic tool for investigation of machine windings. As a base are measurement results of frequency dependencies of the winding admittance. Therefore, relations between different kinds of winding faults and changes of frequency dependencies of winding admittances should be determined. Much research work is done in that field, which is aiming to determine the sensitivity of this method and to develop the recognition criteria with regards to the type and range of faults. This paper presents the comparison of measurement results of the admittance performed on the electric machine windings of different construction. The influence of turn-to-turn faults between adjacent winding wires on the admittance waveform has been also investigated.