用于局部放电在线监测的高频微电流传感器

High Frequency Micro-current Sensor for On-line PD Monitoring

通过建立的物理和数学模型 ,推导了用于局部放电在线监测的高频微电流传感器的传递函数和频率特性计算公式 ,运用 Saber的交流小信号分析工具 ,研究了传感器线圈匝数、杂散电容和负载电阻的变化对通频带宽和灵敏度的影响 ,进一步分析了与传感器通频带宽和灵敏度关系最为密切的参数。结合实际应用 ,给出了几种不同要求下线圈匝数和负载电阻的选择 ,最后 ,用建立的传感器模型仿真了典型的局部放电时域及频域信号。

According to the physical and mathematic model of high frequency micro-current sensor for on-line PD monitoring, Computational formulas of transfer function and frequent characteristic are presented. It discusses the effects of sensor coiling number, stray capacitance and loading resistance on pass-band width and sensitivity by AC Small Analysis in Saber. Then it focus on the most important parameter concerning pass-band width and sensitivity. Considering practical application and different requirements, the values of sensor coiling number and loading resistance are given. Finally, the typical simulated PD signals in time and frequency domains are gained by sensor model established in this paper.