PARTICLE INITIATED FOV OF HYBRID CYLINDRICAL INSULATING SPACERS UNDER AC AND DC VOLTAGES IN AIR FOR DIFFERENT ELECTRIC FIELD CONFIGURATION - AN EXPERIMENTAL APPROACH

The ever – increasing voltage levels in electrical power systems need to enhance the power distribution and transmission system. The insulation failure is mainly due to the high voltage stress. The dielectric strength of air is greatly influenced by the presence of insulating surfaces. In the present research work the new hybrid cylindrical insulating spacers such as PMMA – PP, PP – NYLON and NYLON – PMMA and the orientation of hybrid cylindrical insulating spacers has been studied. The flashover performances are carried out experimentally in air as insulating media for different electrode configuration such as uniform electric field (Plane – Plane), non-uniform electric field (Needle – Plane) and moderately non-uniform electric field (Hemisphere rod – Plane) under AC and DC voltages. The effect of conducting floating particles is also carried out for different electrode configuration under AC and DC voltages. The experimental investigations shows that NYLON – PP and NYLON – PMMA hybrid spacers has highest flashover voltage (FOV) under AC voltages, in case of DC voltages PP – NYLON hybrid spacer gives highest FOV. The hybrid spacer PP – NYLON has more effective under AC voltage, whereas in case of DC voltage PMMA – NYLON has more effective with conducting floating particles.