All post insulators comply with gb8287 1 the provisions of technical conditions for high voltage Post Porcelain Insulators and gb12744, pollution resistant outdoor rod post porcelain insulators, also comply with the provisions of international standard iec168 test of indoor and outdoor porcelain or glass post insulators for systems with nominal voltage higher than 1000 V and IEC publication 815 guide for selection of insulators under polluted conditions.
The insulator has high mechanical strength, low dispersion and safe and reliable operation. In order to test the low-temperature mechanical properties of the product, the freezing test of zsw1-110 / 4 insulator was carried out by simulating the change of outdoor temperature in winter in the low-temperature laboratory of the Institute of water science. After several temperature cycles, the test crystal is subjected to bending failure test at low temperature. The test results show that the bending failure strength of insulators at - 40 ℃ has no obvious change compared with room temperature.
The pollution resistance of insulators mainly depends on the structure of products and the shape of umbrella skirt. A lot of work has been done in this regard. Through design optimization, artificial pollution test optimization and natural pollution test optimization, the insulator umbrella skirt with large and small umbrellas and ribs under the umbrella is determined. The insulator with rated voltage of 126kV and 252kV, bending failure load of not less than 12kV and creepage specific distance of 25mm / kV developed with the umbrella skirt.
Under the equivalent salt density of 0.12mg/cm2, it can withstand the high operating phase voltage for a long time, that is, the creepage distance of insulator level III, and can withstand the pollution of equivalent salt density of level IV. Insulators with rated voltage of 550kV and creepage specific distance of 25mm / kV can operate for a long time under the equivalent salt density of 0.06mg/cm2. The pollution resistance level of insulator is leading in China. Its equivalent salt density is one third higher than that of similar products with the same climbing distance and equal diameter umbrella skirt. The artificial pollution withstand voltage test of insulation is carried out by northeast electric power test and Research Institute. The results show that the withstand high salt density of insulator with creepage specific distance of 31mm / kV is 0.25mg/cm.
