10kV新型线路避雷器连接方式关键设计技术参数研究OA

An electrical connection type based on magnetic force is designed to achieve live replacement of line arresters.The temperature rise and electrodynamic force of the metal connecting conductor under short-circuit current and lightning current impacts are simulated and calculated,and the selection of the cross-sectional area of the connecting conductor and the magnetic force of the magnetic plug is given.The temperature rise simulation shows that the short-circuit current under extreme conditions will cause a sharp increase in the temperature rise of the connecting conductor.Choosing the connecting conductor with a cross-sectional area of 25 mm2 or more can withstand the impact of the short-circuit current,while lightning current impact will not cause the connecting conductor to ablate.The maximum tempera-ture rise under the action of 65 kA lightning current is 2.26 ℃,and the maximum temperature rise under the action of 100 kA lightning current is 5.35 ℃.The simulation of electrodynamic power shows that the electrodynamic power received by the connecting line is positively correlated with the square of the short-circuit current,and the distribution of electrodynamic force has a double frequency characteristic.The maximum equivalent electrodynamic force under short-circuit current is 152.5 N.Considering the maximum short-circuit current and the gravity of the connecting conductor,the magnetic force must be greater than 152.95 N to ensure the dynamic stability of the connecting conductor.The huge electrody-namic force generated by lightning current impact will cause the magnetic plug to briefly detach,but it will quickly restore suction under the action of magnetic force.