测量ns级脉冲大电流的折带式分流器

Fold Band Shunt Used in Measuring the ns-grade Pulse Current

介绍了一种结构紧凑的折带式分流器,它可用来测量幅度为几十kA、脉宽为十几ns的脉冲大电流。经定标,此分流器的动态电阻为12.57 mΩ,响应时间为1.21 ns。采用该分流器测得Spark-04型脉冲功率调制器的电子束流强度约47 kA,与采用其他方法测量的结果基本一致。

A compact fold hand shunt, which is simple to be made, is constructed and studied. The equation of respond time of this kind of shunt is deduced. The shunt can be used to measure the pulse current with the intensity of dozens of kA and the width of 10～100 ns. To measure pulse current, the shunt we used most is coaxial shunt. In some condition we also use Rogowsky coil to measure pulse current. This kind of shunt often used in condition that the coaxial shunt and other means are not convenience to be used. According to the using condition we design the resistant to be about 10 mΩ. For the reason that the shunt should have a fit dimension, we use stainless steel band as the resistant material, whose thickness and width are 0. 02 mm and 80 mm respective. Based on analyzing the influences of the capacitance and inductance to the respond of the shunt, the clearance width of the band we choose is 6mm. We also considered the effect of heat and electromagnetism when the pulse current is in action. In the condition that the intensity and the width of the pulse current is up to maximum, the electromotive power and heat stress and temperature change are 1370N and 10MPa and 3. 6℃. For the reason that the electromotive power and heat stress are so large, some actions to avoid the shunt from broken are taken. The dynamic resistance and respond time are calibrated to be 12. 57 mΩ and 1.21ns respectively. The calibrated respond time is according with the value get from the equation we deduced. The shunt has been used to measure intense beam current from vacuum diode of Spark-04 Intense Relativistic Electron Beam Accelerator and the value of beam current is about 47 kA. This experimental result is approximately accorded with the result of other measure approaches. Some analysis with the experimental result is done. as well as some ideal to improve the shunt is given.