Influence of frigid conditions on the mechanical properties of transformer insulating spacers

The frigid conditions can change the mechanical properties of transformer insulation spacers, which are closely related to transformer's ability to withstand short circuit. However, until now, previous studies mainly focus on the mechanical properties of insulation spacer above zero temperature, lacking in the influence of extreme low temperature on the mechanical properties of transformer insulation spacers. In this paper, the elastic modulus is used to evaluate the mechanical properties. The experimental results show that, when insulating spacers are exposed at constant low temperature, the elastic modulus increases with the temperature decreasing, and the elastic modulus increases faster when the temperature is under oil freezing point. As the number of low temperature cycles increases, the elastic modulus approaches a linear decrease. And it's found that the elastic modulus decrease with the decreasing of the target low-temperature, and decrease faster when the temperature is under freezing point of oil. The experiment results can be used to evaluate the influence of the different frigid conditions on the mechanical properties of transformer insulation spacers and provide guidance on the protection of power transformers in frigid environments.