Features of simulation capacitive leakage currents of electric motor stator winding insulation

Abstract

The paper considers the features of building a model of induction motor stator winding insulation capacitive currents. It is shown that for the correct display of capacitive leakage currents by the model in the case of using PWM inverters, it is necessary to take into account the presence of a large number of conductors in the stator slot, which implies considering the winding phase as a long line with parameters distributed along its length, such as the active and inductive resistance of the winding itself as well as capacitive and active insulation resistance components. Such a construction of the model makes it possible to reproduce the appearance of wave phenomena of leakage currents associated with large values of the voltage derivatives, characteristic of the operation of inverters with PWM. It is also shown that for the case of supplying the stator winding from a source of industrial frequency (50/60 Hz) sinusoidal voltage, the model with lumped parameters makes it possible to provide a calculation with sufficiently accurate reproduction of the quantitative characteristics of capacitive leakage currents.