The high-frequency induction machine parameters and their influence on the common mode stator ground current

The representation of induction machine parameters, according to the high-frequency (HF) behavior of the machine impedances, has been previously presented in the literature. Methods to extract them from the measured HF machine impedances have been also presented. It has been found that a representation of the distributed stator winding-to-stator frame capacitances by two capacitances, for lower frequencies (1 kHz ... 100 kHz) and higher frequencies (1 MHz ... 10 MHz) is very convenient for studying HF effects in induction machines. Until now, a method to calculate these two capacitances from the machine design data was not available. In this paper, a method to calculate the HF model capacitances from the machine design data is presented, and further, based on several experimental investigations, their physical explanation is given. Also, a new frequency-response model of the induction machine is proposed and the common mode stator ground current is calculated. The physical interpretation of all these HF machine parameters is given, and their influence on the common mode ground current is shown.