基于法拉第电磁感应法的脉冲强磁场测量方法

由大电流对负载高压放电产生的脉冲强磁场磁场强度高,随时间变化剧烈。为解决测量系统不仅要有较宽的量程,还要有很快地响应速度的问题,研究了根据法拉第电磁感应定律,通过线圈感应电动势确定磁通量的变化,进而得到磁场的强度的测量方法。从线圈各匝间的绝缘和多次测量使用考虑,采用了单匝线圈作为测量元件,并通过良好的接地和屏蔽措施提高测量系统的稳定性和抗干扰能力。将磁场测量结果与通过电流计算的理论值比较,误差很小,这验证了方案的可行性。线圈制作简单,只要解决好屏蔽问题,就可以作为一种测量强磁场的有效手段。

Measurement of High Pulse Magnetic Field Based on Faraday Electromagnetic Induction

High pulse magnetic field is produced by high voltage discharge in short time.The magnetic strength of high pulse magnetic field is high and changes acutely along with time.So the measuring system must be wide span and swift response speed.According to the Faraday electromagnetic induction law,the induction electromotive force of winding reflects the variety of magnetic flux,then the magnetic strength can be gotten.Considering winding insulation and iterative measurement,the number of winding turn should not be excessively large,the single winding is used as measuring element.The end of enameled wire along with induction electromotive force passes through a stoma insulation tube and links the core of coaxial line.Another end of the enameled wire links the screen layer of coaxial line.The inside diameter should approach the diameter of enameled wire,which can keep the enameled wire straight in the section and reduce magnetic induction from this lead wire.The measuring system stability and anti-interference capability are improved,and the magnetic strength value can be experimentally measured.Meanwhile,the discharge current was also inspected.According to the current value,the academic magnetic strength can be acquired.Compared the two values,the discrimination is little,so the method is feasible.Manufacturing the winding is simple and the key problem is screen.As long as screening these interference and grounding effectively,the testing precision can be ensured.Experimental results indicate the Faraday electromagnetic induction winding method is simple and veracious in testing high pulse magnetic field.