同轴电容分压器结构分析  

Structural analysis of coaxial capacitive voltage divider

作　　者：余丹[1] 徐雁[2] 孙文[2] 

机构地区：[1]咸宁职业技术学院信息与软件工程系,湖北咸宁437100 [2]华中科技大学电气与电子工程学院,武汉430074

出　　处：《电测与仪表》2015年第4期107-111,共5页Electrical Measurement & Instrumentation

摘　　要：同轴电容分压器能有效避免寄生电容的影响,抗电磁干扰,稳定性良好。在同轴电容分压器中,电场分布不均匀,绝缘强度与同轴电容的半径有关,文章给出了同轴电容的半径选择原则。同时,温度对电容分压器精度的影响与其结构有关,文章建立了数学模型,分析了内外半径、壁厚、膨胀系数、温度等因素对误差的影响。计算与仿真的结果表明:固定外径和内径的比值为e,较大半径、薄的圆筒壁厚和低膨胀系数的材料可以使温度对测量精度的影响降到最低,同时保持最好的耐压能力。Coaxial capacitive voltage divider shows good stability and unti-electromagtnetic interference, can effective-ly avoid the influence of parasitic capacitance.Distribution of electric field is not uniform in coaxial capacitive, and the dielectric strength is related to the radius of the coaxial capacitance.The selection principles of the radius of the coaxi-al capacitance are presented in this paper.At the same time, the influence of temperature on the accuracy of capaci-tive voltage divider is related to its structure.This paper establishes a mathematical model to analyze the influence of inner and outer radius, thickness of cylinder, expansion coefficient, and temperature on the accuracy.Calculations and computer simulation results show that the key to enhance the accuracy of capacitor divider is to keep the ratio of inner and outer radius e , choose metal material of low expansion coefficient , proper thickness of cylinder and larger radius .In that case,the coaxial capacitive will has the best insulation characteristic.

关 键 词：同轴电容分压器 结构分析 温度 数学模型 

分 类 号：TM53[电气工程—电器]