电磁兼容性测试用冲击电压分压器设计及实现

基于"场-路"耦合的思想,通过电磁场仿真计算提取电阻分压器的杂散参数,建立了冲击电压下电阻分压器的等效电路模型,进而研究了电阻分压器结构参数对测量结果的影响.依据仿真分析结果,设计并实现了电磁兼容性测试用10kV冲击电压分压器与冲击电压测量系统.经测试该系统测量冲击电压峰值的扩展不确定度、测量波前时间的扩展不确定度、测量半波时间的扩展不确定度等,均满足电磁兼容性测量要求.

Numeric-simulation design and calibration of 10 kV impulse voltage divider

Based on field-circuit equivalence,using hybrid finite element-analytical approach,the mutual capacitance and mutual inductance of a 10kV impulse voltage divider are extracted.By analyzing the extracted parameters,the distribution pattern of mutual capacitance is discussed.The Milne method is used to analyze an equivalent circuit,in which the mutual capacitance and inductance are used as circuit parameters and as a result the simulation of a virtual divider is accomplished.To achieve the consistence between simulation and measuring results, a 10kV impulse voltage system is established and calibrated by National Institute of Metrology.According to the step impulse test,the partial response time is 2.73ns,the overshoot is 10.33% and the stable time is 20.46ns.The expanded uncertainty of the impulse peak voltage is 0.192%,the expanded uncertainty of front time is 1.5%,and the expanded uncertainty of half-wave time is 1.58%,which is qualified for electromagnetism compatibility.