Effects of Non-linear Composite Barriers on Tree Growth in Solid Insulation

The consequences of zinc oxide (ZnO), Aluminum oxide ( 3 2O Al ) and Titanium oxide (TiO2) on tree growth have been comprehensively investigated in this paper. Zinc oxide (ZnO), II-VI compound semiconductor, is used in varistors in power insulation life. Due to its excellent electrical properties such as nonlinearity of current-voltage (I-V) characteristics, high fast-transient response and high discharging capability, it is extensively used in polymeric insulation materials. Titanium oxide (TiO2) polycrystalline is used in electronic devices as varistor (voltage dependent resistor). Titanium oxide is also used for surge arrester applications due to its nonohmic behavior. In present work, zinc oxide (ZnO) and titanium oxide (TiO 2) are used in clear polyester resin as barriers. High voltage 28kV rms is applied. Polariscope is used to investigate the behavior of growth of tree on regular intervals. The results of zinc oxide (ZnO) barrier specimens are compared with titanium oxide (TiO2) barrier specimens. When zinc oxide (ZnO) barrier and Titanium oxide barrier specimens were tested, the life time of zinc Oxide barrier was more than the titanium oxide barrier. It is experimentally proved that by using semi conducting filler material with nonlinear conductivity characteristics can raise resistance against electrical tree propagation. Index Term-Zinc oxide, Titanium oxide, Insulation, Barrier,