聚龙一号装置的强电磁干扰对PDV的影响研究

光子多普勒测速系统(PDV)常采用全光纤模式, 操作方便, 已成为材料超高压动态实验获取动力学特性的重要诊断技术。测速范围和精度与光电传感器和数据采集仪器有关, 激光到达靶面后返回光电转换器, 速度由多普勒引起的频率变化直接解读。聚龙一号装置是开展材料动态实验的重要平台, 放电电流峰值5~8MA, 0~100%上升时间300~750ns。在装置放电过程中, 靶室和大厅中的强电磁干扰可以达到10~300MHz, 当干扰耦合进返回光信号后, 导致速度剖面解读困难。采用聚四氟乙烯绝缘膜和导电铝膜包覆测速探针很好地抑制了强电磁干扰信号对光信号的干扰, 大大提高了速度测量数据的有效性。

Study on effect of strong electromagnetic interference of PTS facility on photonic Doppler velocimetry

Photonic Doppler velocimetry(PDV)is usually based on all-fiber mode, which is easy to operate and has become an important diagnostic technology for ultra-high pressure dynamic material properties experiments.The range and accuracy of velocity measurement are related to photoelectric converter and data acquisition instruments.When the optical signal reflected by the target returns to the photoelectric converter, the frequency of laser intensity is changed by Doppler effect.The PTS facility is an important platform for dynamic material properties experiments.The peak current is 5-8 MA and the 0-100%rise time is 300-750 ns.During the loading process, there is strong electromagnetic interference in the target chamber, whose frequency are 10-300 MHz.When the interference is coupled into the return optical signal, the velocity data will be covered.Using PTFE insulating film and conductive aluminium film coated velocity probe can suppress the interference of strong electromagnetic interference signal to optical signal, and greatly improve the validity of velocity measurement data.