Analysis on overvoltage in electromagnetic launch under the no-load condition
The launching experiment on a small electromagnetic railgun system has been carried out in this paper.The launcher is a series-augmented railgun with the caliber of 30mm and the rails effective length of 3.0m.The armature mass is 40g and the desired muzzle velocity of the armature is not less than 2000m/s.The power source is a pulsed power supply of capacitor energy storage type, whose rated energy storage is 1.18MJ and rated voltage is 13.0kV, and the pulsed forming network consists of 10 pulse forming units with the same parameters and structures.The damages of the crowbar diodes occurred in one launching experiment.The subsequent investigation found that the armature did not enter the orbit and the launching system was in a state of no-load due to the failure of the automatic loading mechanism of the armature.Dissecting and analyzing the damaged diodes, the conclusion is that the diodes are breakdown due to overvoltage.Based on the circuit structure of the pulsed forming network and the characteristics of the main components of the launching system, the mechanism of the overvoltage is obtained through the theoretical analysis, the equivalent parameter measurement and the simulation verification, and the solutions are given.The research shows that the generation of overvoltage is related to the no-load state of the pulsed power supply, sequential pulse discharge of the pulsed forming network and the characteristics of the crowbar diodes.When the system is in a state of no-load, the pulse discharge of the pulsed forming units of the first group can cause overvoltage on the crowbar switches of the pulsed forming units of the second group that do not start to discharge.The maximum amplitude of the overvoltage is close to twice the rated voltage.The research conclusion is helpful to the determination of component voltage level and the improvement of system safety in the pulsed power supply.
Pulsed power supply Overvoltage railgun Pulsed forming unit
Zhen-xiao LI Shuang-peng HAO Xin MA Yong JIN Hui TIAN Bao-ming LI
National Key Laboratory of Transient Physics, Nanjing University of Science and Technology, Nanjing, China Ordnance Society, Beijing, 100089, China
国际会议
2018 International Conference on Defence Technology (2018国际防务技术会议)
北京
英文
73-76
2018-10-21（万方平台首次上网日期，不代表论文的发表时间）