The effect of pulsed voltages on dielectric material properties

The problem of premature failure of rotating machines fed by inverters appears to be of crucial importance. Understanding of the phenomena caused by this new type of supply on the stator insulation of motors provides enhanced reliability of the inverter/motor set. After identifying the stresses created by this type of device, a study of aging of the materials used as models, and subjected to similar stresses, is undertaken. For the voltage, rise time and frequency under study, the intrinsic part of the aging is studied. The results are presented and discussed according to the nature of the interaction existing between the electrical stress and the material properties.