电磁发射中固体电枢的磁探针测速方法研究

Research on Velocity Measurement of Solid Armature by B-dot Probes in Electromagnetic Launch

为测量固体电枢运动速度应用电磁感应原理,分析了电磁发射中固体电枢所产生的磁场以及B-dot磁探针中的感应电动势,给出了根据磁探针的感应电压信号以及驱动电流信号计算固体电枢运动速度的迭代算法。在小电流、低速运动的模拟实验中,通过探针上感应电压信号的仿真计算结果和实验条件合理设计了探针的结构尺寸,结合实际应用中所遇到的问题加以改进。利用所设计的探针和改进的算法实测电枢的运动速度的结果与实际情况较为符合,该算法可以有效测得电枢的运动速度随时间的变化曲线。

The electromagnetic induction theory is applied to analyze the magnetic field produced by the solid armature and the inducted electromotive force of the B-dot magnetic probes in the process of electromagnetic launch, and then the iterative arithmetic of the solid armature＇s velocity calculation is presented, which is based on the probes, induced voltage signal and the driving current signal. In the model experiment with small current and low velocity, the structure and size of probes is redesigned by analyzing the emulated calculation results of the induced voltage in probes and experimental condition. And the iterative arithmetic is improved or some problems encountered in actual practices. Then the actual measurement experiment of the armature velocity is taken by use of new probes and improved arithmetic. The experiment result shows that, the computed result of experimental data is approximately equal to that of actual situation, consequently the improved arithmetic can effectively get the speed-time curve. Finally the arithmetic＇s feasibility and problems possibly remaining in electromagnetic launch experiments have been analyzed and discussed.