Investigation of space charge in low density polyethylene using field probe technique

Field distortion caused by space charge accumulation in solid insulations represents one of the problems of extruded high voltage D.C. cables. The present paper describes a special test method, using a capacitive field probe in investigating space charge distribution in low density polyethylene (LDPE). Specimens of 7 mm thickness were stressed under 100 kV d.c. at room temperature and for different time periods. Results indicate that the (LDPE) insulation layer between electrodes is occupied by positive and negative homo charges. The dependence of space charge distribution on the stressing time is also evident.