Application Of Pulse Pas Prc Extinguishing Device In 500kV Series Compensation

500kV series compensation reduces the impedance of the circuit by connecting the capacitors in series,so as to improve the transmission capacity of the line and the stability of the power grid,but in the process of practical application,there are also problems of MOV pressure release,explosion and false triggering of protection gap,resulting in the shutdown of series compensation equipment.At present,the measures such as improving mov process and strengthening protection gap maintenance still have great limitations,which can not fundamentally solve the industrial problems such as series compensation mov explosion and gap false triggering.In order to explore the solution of series compensation mov explosion and gap false triggering,and improve the reliability of series compensation operation,this paper first studies the principle of series compensation device,MOV and protection gap,as well as the existing problems and control measures,then studies the mechanism of air breakdown in protection gap to form arc,and then studies the principle of high-speed and high-voltage pulse air flow to extinguish arc,According to the principle,the mathematical model is established,and the simulation is carried out by COMSOL software.Then,the power frequency high current and 500 kV ultra-high voltage arc extinguishing tests are carried out on the pulse gas arc extinguishing device.Finally,the pulse arc extinguishing devices on 110 kV and220 kV lines are summarized and analyzed.The results show that the characteristics of the arc formed by the gap breakdown of the series compensation protection are consistent with that of the conventional air breakdown arc,both belong to the power frequency arc,but the duration is long and the short-circuit current is large.The simulation results show that the arc is affected by the jet flow.In terms of position,the effect near the jet port is greater than that far away from the jet port,but it is less than 3000 K.At this time,the corresponding time point is 2.24 ms,and the arc extinguishing speed is very fast.The power frequency high current and 500 kV ultra-high voltage test shows that under the condition of high current and ultra-high voltage,the pulse arc extinguishing device can operate correctly,diffuse the arc heat,neutralize the charged particles of the arc,and extinguish the arc in a short time.The test results on 220 kV transmission lines show that the continuous current power frequency short-circuit arc is generated when the gap air is broken down by lightning,and these arc are extinguished before the relay protection action,and no line trip occurs.The gap with pulse gas arc extinguishing function,that is,the pulse gas arc extinguishing device can extinguish the arc when the series compensation protection gap is triggered by mistake or by itself,and prevent the bypass of series compensation.Compared with the use of parallel insulator strings on the line,it does not need insulation coordination and is more convenient to use.