Analysis of Thermal Characteristics of Switch Cabinet with Multi-Physics Field Coupling Method

Overheating is one of the key factors affecting the normal service life of switch cabinets. Therefore, it is of great significance to find out methods to reduce the temperature rise of the switch cabinet. In this paper, based on a 400V low-voltage switchgear, a three-dimensional simulation model is established using the electromagnetic-thermal-fluid multi-physics coupling method. Under the conditions of simulating natural convection, considering eddy current effects, proximity effects, and skin effects, heat transfer methods such as thermal conduction, thermal convection, and thermal radiation are comprehensively used to calculate and analyze the thermal distribution characteristics of the distribution cabinet shells and three-phase current-carrying conductors. Moreover, a temperature-rise experiment is performed to verify the feasibility and accuracy of the electromagnetic-thermal-fluid multi-physics coupling method and the accuracy and effectiveness of the calculation model under the current simulation conditions. In addition, in order to reduce the temperature rise of the cabinet, A strategy for optimizing the switchgear is proposed, and the heat distribution characteristics of the optimized model is calculated using the multi-physics coupling method. The results show that the temperature rise of the switch cabinets of the scheme has been reduced in different degrees, which effectively solves the overheating problem of the switch cabinet.