Study on mechanical properties of insulation pull rod for UHV AC GIS circuit breaker

As the key part of GIS which is widely used in UHV AC power grid, insulation pull rod needs high mechanical performance to ensure the safe operation of GIS circuit breaker. In this paper, the mechanical properties of insulation pull rod for UHV GIS circuit breaker were studied by simulation and static mechanical experiments. Firstly, the stress distribution of the pull rod under bending force was simulated. Then, sensors were arranged on the surface of pull rod according to the simulation results. Finally, bending and tensile experiments were carried out to get the strain changes of pull rod's surface. The experiment results showed that the tensile strength of the pull rod is much greater than the bending strength. And the closer to the fixed end, the greater the strain was in the bending experiment. As for tensile experiment, the strain measured by each sensor were very close. The maximum strain measured were 10391με and 9104με respectively in the bending and tensile experiments, and the corresponding maximum force is 6.77kN and 290kN, but no yield phenomenon was detected. The experimental data can provide guidance for the manufacture of insulation pull rod and enhance the reliability of UHV GIS transmission technology.