The measurements of electric filed vector distribution in propylene carbonate

It is necessary for electrical insulation diagnosis to obtain information about the electric field distribution and the space charge distribution in insulation materials. We have investigated the measurement of nonuniform electric field vector distributions in liquid dielectrics using an original method based on electrooptic Kerr effect and CT method. We carried out the time series measurement of electric field vector distribution in propylene carbonate. When the DC voltage pulse of 50 msec width was applied to a sphere-to-plane electrode system, electric field vector distributions on some measured planes were measured at intervals of 1 ms. Distribution at starting voltage pulse was almost the same as that of a static field. The electric field vector distribution seemed to be disturbed after a certain time, and the electric field vector distribution could not be measured after it. But, the observation of the time when the ldquodisturbancerdquo started would be able to give the behavior and electric characteristic of the liquid.