SF

6

is widely used in switching equipment due to its excellent ability to extinguish the arc

however

the SF

6

circuit breaker often undergoes liquefaction in extremely cold environments

and the solution to the liquefaction problem of the existing porcelain column circuit breaker is not satisfactory.In order to solve this problem

a 110 kV porcelain type SF

6

circuit breaker anti-liquefaction intelligent unit and built-in heating structure suitable for use in extremely cold environments are designed.Establishing a 3 D

model of porcelain type circuit breaker based on workbench software

perform electric and temperature field simulation for different schemes

and determine the intelligent unit technical route and carry out prototype design.In this paper

a low temperature test environment is built to test the operation effect of anti-liquefaction intelligent unit components.The prototype is installed and tested in Jiagedaqi 110 kV substation in Hulunbuir area.The test results show that the anti-liquefaction intelligent unit works stably with the circuit breaker

and the temperature measurement error is within 1 ℃

the anti-liquefaction device installed in the inner bottom of the insulating bushing of the 110 kV porcelain type SF

6

circuit breaker can ensure that the temperature inside the arc extinguishing chamber can be maintained above the SF

6

liquefaction point when the external environment is at-40 ℃

which meets the requirements for on-site breaking of the circuit breaker.