Abstract:

Aiming at the common industry problem of difficulty in balancing efficient heat dissipation and high-level protection of outdoor low-voltage distribution boxes,the inherent contradiction and limitations of traditional single-layer cabinet design are quantitatively revealed,and collaborative optimization research is carried out.The concept of heat dissipation-waterproofing homologous design is proposed,and a double-layer hollow composite cabinet structure based on the chimney effect is constructed,a synergistic mechanism model of heat-moisture coupling and rainwater retention is established,structural parameters are optimized through simulation and orthogonal tests,and the scheme performance via multi-dimensional tests is verified.The results show that the protection rating of the scheme reaches IP45,the core temperature rise under full load is reduced by 42.7% compared with the industry benchmark,the maximum temperature difference inside the cabinet is controlled within 6.8 ℃,the average annual maintenance frequency is reduced by 87.5%,the average annual failure outage time of a single device is reduced by 92%,and there is no condensation,rainwater ingress or overheating fault during the whole process.A technical path can be provided for the high-reliability design of end-user outdoor power distribution equipment in new-type power systems.

Key words: low-voltage distribution box, passive heat dissipation, waterproof protection, chimney effect, distribution network technology