Investigation On Numerical Simulation And Optimization Of Ventilation System For Indoor Substations

As the mainstream in the future substation construction, the whole indoor substation has been incorporated into urban planning and construction. Currently, the high-voltage and large-capacity power transformer has been placed in the indoor space, it is true that there are many advantages such as conservation of land, noise cancellation and well harmony with the surrounding architecture and so on. However, there are still some disadvantages such as compact layout of electrical equipments and poor ventilation. In addition, the heat dissipation of electrical equipments will change with the electrical load changing, which determines that it can not copy research methods of other ventilation places, only on the basis of their own characteristics and requirements.In recent years, with the rapid rise and development of CFD technology, it has provides a new tool and method for engineering design and optimization of typical electrical equipment rooms’ventilation plans of the whole indoor substation, which can greatly reduce development costs and shorten the design cycle. The field measurement and numerical simulation are combined in this paper. Firstly, typical ventilation problems and their influencing factors of typical whole indoor substations are obtained by field research. Secondly, the targeted theoretical analysis and optimizations are carried out. Finally, research results can be used to guide engineering optimizations and designs to achieve the purposes of the whole indoor substation’s energy saving and stable operations.In this study, field researches and data collections have been done on site, the results show that the amount of heat dissipation of radiator accounts for 77.66% ～85.31% of the total amount of the transformer system loss. The transformer loss is primarily dissipated by radiation, accounting for 55.15%～70.25% of the total heat loss. However, the heat is mainly dissipated by convective for the radiator, the amount of radiation loss only accounting for 2.18%～11.34%.This paper has analyzed a 110 kV whole indoor substation, and the Standard k-s turbulence model is used. The simulation results show that the critical temperature of natural ventilation is 24 ℃, the minimum mechanical ventilation rate is 0.3 m/s under extreme weather conditions in summer. The most significant parameter is forced air inlet width, followed by forced air inlet position, forced air velocity, and natural ventilation velocity.Based on the thoughts of controllable weak flow ventilation, with the premise of not changing substation overall layout pattern, the diversion structures are installed to optimize airflow. For example, installation of the deflector in the air inlet of radiator chamber, at the top of the radiator chamber and in the transformer room vents are proposed. In addition, the single factors affecting the cooling capacity of radiator body have been investigated and the laws on the cooling capacity are obtained.