Analysis And Research On The Anti-Thunder Clearance Of Strong Gas Arc-extinguishing Device Based On Jet

Thunder and lightning activities are still natural disasters that human beings cannot control.Thunder is the main cause of power grid failure.With the rapid increase of the scale of power grids and the continuous improvement of people's living standards,the requirements for the stability of power supply are also increasing.The traditional lightning protection theories and devices have defects and deficiencies,lack of pertinence and matching,and face randomness and suddenness.The power grid damage control effect is strong,and the lightning strike rate and accident rate are high.To this end,this paper develops a strong gas arc lightning protection device that can effectively reduce the lightning trip rate and accident rate.This paper first analyzes the characteristics of the arc,including the physical structure of the arc,the voltage characteristics,the thermodynamic characteristics of the arc plasma,the heat dissipation characteristics and the process.The energy loss of the arc is mainly through the way of heat radiation,heat convection and heat conduction.It can be known that the high-speed gas acts on the arc,which can accelerate the de-free process of the arc,and also accelerate the arc convection to dissipate energy.The arc-extinguishing theory analysis of the blow-off arc lightning protection device provides the basis.Analyze and study the existing arc black box model,and proceed from the principle of energy balance,and establish the Mayr arc model through MATLAB to simulate the natural extinction process of the arc and analyze the current and voltage during the natural extinction of the arc.The high-speed gas field model is analyzed,and the high-speed gas shock wave model in the confined space of the arc extinguishing cylinder is established.Combined with the arc model,the high-speed gas field model and the high-speed gas shock wave model in the confined space of the arc extinguishing cylinder,the coupling model between the arc and the high-speed gas field is established,and finally the plasma-based high-speed gas arc-extinguishing model is established.From the perspective of mathematical models,it provides a demonstration for the theory of strong gas arc lightning protection devices.Through the simulation of COMSOL Multiphysics,the high-speed gas is applied to the arc and extinguished.It is concluded that the high-speed gas intercepts the arc at the arcing point.At this time,the gas pressure is extremely high,and the dielectric strength of the internal space of the arc extinguishing cylinder is extremely large.The 50%discharge voltage characteristics and the volt-second characteristics of the device were studied by the impulse voltage experiment to ensure that the device can protect the insulator jfrom the insulator discharge in the lightning strike tower.Then,the power frequency voltage arc extinguishing experiment was carried out and the arc extinguishing process was recorded by a high speed camera.After verifying the effectiveness of the device,the experiment is carried out on the 110kV line to analyze the operation effect of the device under actual complicated conditions.It is proved that the strong gas and arc extinguishing device is effective in extinguishing the arc and ensuring the normal operation of the line.