It is very important to precisely calculate the temperature rise of GIS

which may aid the optimization design

shorten the development duration and reduce the development cost. For one 126 kV three-phase-in-one-tank type GIS

taking the contact resistance

proximity and skin effects

and eddy current effect into account

we firstly developed an electromagnetic – thermal coupled model

and then analyzed the loss distribution and temperature rise characteristics under the action of 2 200 A current. In order to further investigate the influence of gas flow

we proposed an electromagnetic – thermal – fluid coupled model for the GIS model

and compared the temperature rise calculation results based on two difference methods

i.e.

only considering the GIS inner SF

6

fluid domain

or considering both the GIS inner SF

6

fluid domain and GIS outer air fluid domain. According to the relevant national standard requirement

experiments for temperature rise were carried out under the same current of 2 200 A. It is revealed that the loss density of disconnector conductors is higher than that of circuit breaker conductors

the calculation precision of the last method is the highest

and the relative error is less than 10%. The results can provide an effective method for optimization design of thermal characteristics of GIS

and technical references for other power equipment.