Study On Early-warning And Emergency Disposal Methods Of Sulfur Hexafluoride Leakage In Substation Main Transformer Room

Sulfur hexafluoride gas has insulation arc-extinguishing characteristics and anti-breakdown effects,and is widely used in electrical equipment in substations.Substations in urban areas are mostly installed in densely populated areas.Once the leakage of sulfur hexafluoride gas from electrical equipment in the main transformer room,when the concentration is far beyond 1000ppm,the oxygen content may be reduced to below 19%,and workers and maintenance personnel will face potential suffocation risks.In order to promptly warn and take emergency disposal measures to reduce accident casualties after sulfur hexafluoride leakage,this paper studies the early-warning and emergency disposal of the leakage of sulfur hexafluoride in the main transformer room of the substation.Firstly,based on fluid mechanics simulations,this paper studies the gas diffusion concentration distribution of sulfur hexafluoride leakage at different leakage points in the substation space,collects and organizes the simulation data,and determines the first monitoring of sulfur hexafluoride exceeds the concentration threshold sensitive area,based on which to determine the location of the sensor monitoring points,and analyze the simulation results.By studying the different leakage locations and leakage orifice diameter in the main transformer room,the coupling relationship between the leakage time and the leakage orifice diameter and the concentration is obtained,and an early-warning model of sulfur hexafluoride leakage in the main transformer room of the substation is established by regression fitting.Then,the composition and construction method of the emergency disposal model of sulfur hexafluoride leakage in the main transformer room of the substation is introduced,and the model is constructed by numerical simulation.The emergency recycling device of this model can recover the sulfur hexafluoride gas leaked into the air,so that the concentration of sulfur hexafluoride in the space is kept stable within a safe concentration range,and the recycling time prediction model can predict the time required for recycling.Finally,based on the constructed sulfur hexafluoride leakage early-warning model and emergency disposal model of the substation main transformer room,a system for early-warning and emergency disposal of sulfur hexafluoride in the main transformer room of the substation is constructed,and combined with the substation safety management data,the emergency rescue of sulfur hexafluoride leakage can be determined at the first time.Documents to guide on-site personnel in emergency handling and safety protection to improve the level of intrinsic safety of the substation.The main research contents are as follows:(1)Using the diameter and location of the leakage as variable parameters,a large number of monitoring points are set to simulate the leakage and diffusion of sulfur hexafluoride in the main substation of the substation under different variables.According to the simulation results,the sensor setting points of the sensitive area of sulfur hexafluoride concentration was analyzed and determined,and the leakage of sulfur hexafluoride could be found in the first time,and analyze the simulation results.Using regression fitting methods,in a large amount of simulated data,the data relationship between the leakage time and the diameter of the leakage orifice and the concentration was obtained,and an early-warning model for sulfur hexafluoride leakage in the main transformer room of the substation was established by MATLAB software.(2)The composition and construction method of the emergency disposal model of sulfur hexafluoride leakage in the main transformer room of the substation.The suction pressure of the vacuum pump is used as a variable parameter to simulate the recycling of sulfur hexafluoride in substations.Based on the simulation results and referring to the cost of the vacuum pump,the suction pressure of the vacuum pump is determined.The determined suction pressure is used to simulate the recycling of sulfur hexafluoride in underground substations at different leakage orifice diameters and leakage locations,and the simulation results were analyzed to obtain the relationship between the recycling time of the emergency recycling device.(3)Based on the early-warning model and emergency disposal model of sulfur hexafluoride leakage in the main transformer room of the substation,and combined with the substation safety management data,construct an early-warning and emergency disposal system for sulfur hexafluoride leakage in substations,implement timely warning of sulfur hexafluoride leakage,and promptly and safely evacuate staff.Sulphur hexafluoride was recycled immediately after the warning to reduce its concentration to dangerous levels in the shortest time.With reference to the substation safety management data,the documents needed for emergency response will be located at the first time,and emergency measures will be determined to improve the substation’s intrinsic safety level.The results show that the models and methods proposed in this paper can be applied to other similar substations,provide theoretical basis for early-warning of sulfur hexafluoride leakage in substations and predict the consequences of accidents,and formulate emergency response plans for accidents,and provide technical support for effectively avoiding or reducing the consequences of accidents.