Investigation of AC and DC Breakdown Behavior on Different Solid Insulating Materials

Population growth and developments in the world increase the demand for electrical energy every year. With the investments made to meet this demand, high voltage facilities are enlarged, voltage levels are increased and power equipment capacities are further challenged. Therefore, insulation coordination is of great importance for the continuity of the power systems. Since breakdown strength is the factor that determines the usage area and service life of insulation materials, it should be taken into consideration for the proper insulation design. One of the factors affecting the breakdown strength is the type of applied voltage. For this reason, the breakdown performance of insulating materials should be investigated under different types of voltages. In this study, the breakdown performances of presspaper, polyethylene terephthalate (PET) and styrene-butadiene rubber/natural rubber (SBR/NR) samples were investigated under AC, positive DC(+) and negative DC(-) voltages. Experiments were carried out in Yildiz Technical University High Voltage Laboratory.