Analysis of Condensation Problem in High Voltage Switchgear and Design of Anti-condensation System

Abstract The southern region is hot, rainy and humid, and the switchgear is prone to moisture and condensation during long-term operation in this environment, causing partial discharge and other failures. To solve the problem that the switchgear is prone to condensation, this paper studies the conditions for the condensation phenomenon and analyses the condensation temperature calculation curve based on the air temperature and relative humidity in the cabinet. Then a three-dimensional model of the switchgear was established, and the thermal-electric coupling finite element simulation was performed to obtain the spatial temperature distribution of the switchgear under long-term operation and different humidity states. The simulation results are combined with the condensation temperature calculation curve to study the condensation situation of the switchgear under different conditions and the parts prone to condensation. Finally, according to the analysis results, a moisture-proof and anti-condensation control and early-warning system based on optical fiber temperature and humidity sensor is provided to detect the data in the cabinet and conduct comprehensive research and judgment, which provides theoretical basis for anti-condensation and intelligent operation and maintenance of switch cabinet.