Study On The Power Frequency Continuous Current Arc Of Explosion Extinguishing Lightning Protection Gap

As a huge disturbance,lightning strikes a great threat to the security,reliability and stability of the power grid,and seriously endangers all the fields of the national economy.Lightning flashover of transmission line after the formation of arc power,resulting in protection circuit breaker tripping,resulting in power system blackouts,but also may be accompanied by hardware security risks,insulator damage,even burn out the transmission line break accident.Aiming at the bottleneck and defect of the existing lightning protection method,a kind of explosion and lightning protection gap with double functions of common parallel gap and cut off power frequency continuous current arc is studied.Based on the analysis of arc V-I characteristics,arc voltage gradient,arc temperature,diameter and other parameters characteristics,studies the process of change of the role of air blast arc energy under the effect of airflow on the arc medium recovery strength.Analysis of the physical characteristics of the explosive explosion,establish model through the internal and external problems of explosive,and gives the calculation formula of explosion shock wave peak overpressure,impulse time and other parameters,analysis of the air blast wave and the formation and propagation of the target damage,at last integral method based on the established model under the effect of air blast arc.Using FLUENT finite element software process of the blast effect of arc simulation,analysis of the blast effects on the arc temperature field,velocity field and temperature and velocity in different position of the arc tube changes,the blast triggered response time test,air blast arc cutting test and quenching time the test,verified the correctness of continual cut blast flow arc theory.From the camera and antiaircraft oscilloscope acquisition test image and waveform shows that the newly formed power frequency arc,arc gap lightning protection rapid response,immediate high-speed explosion impact air arc,arc suppression of transient process of development,and cut off the arc at about 4ms.Further analysis of the actual explosion interrupter gap lightning protection device operation,on-site operation is good,not the lightning trip,the lightning explosion line that arc gap device capable of quick action,the blast can effectively and quickly cut off the power frequency freewheeling arc.