Abstract:

Through the analysis of the heating and heat dissipation mechanisms of the cubicle gas-insulated switchgear (C-GIS), the eddy current simulation of the main electrical circuit of the 40.5kV/4 000A equipment is completed, and the design of the conductor of the main electrical circuit is optimized. Through increasing the thickness of the main conductor by 3mm, the eddy current loss is reduced, and the single-phase resistance of the circuit decreases from 34 μΩ to 22 μΩ. According to the temperature rise simulation of the main electrical circuit, the heating position of the circuit breaker pole is determined, the heat dissipation structure is analyzed, the gas convection air duct is improved, and the gas convection situation inside and outside the switchgear cabinet is simulated. The prototype of the switchgear is manufactured and a temperature rise test is carried out. The results show that the maximum temperature rise reduction of the static terminals of the circuit breaker with the improved pole heat dissipation scheme is approximately 15.4 K under the condition of forced air cooling.

Key words: gas insulated switchgear (GIS), heat transfer, heat dissipation area, convective heat transfer, temperature rise control