摘要
谐波问题的分析与控制是保证高压直流输电系统正常运行的重要内容。为了寻找最适当的测量方法,需要对电压谐波测量进行深入研究。直流电压互感器(DCVT)是测量直流输电系统电压的重要设备。本文介绍与分析了阻容式直流电压互感器的主要组件的特性,如同轴电缆、A/D与D/A转换器、光耦合器,详细分析了分压器的对地杂散电容对电压互感器频率响应的影响,非理想状态下元器件对测量误差的影响。理论分析指出选择一个合适的并联电阻的电容可以减小分压器对地杂散电容的影响,并且可选择精密电阻和电容来减少测量误差。实验结果表明,阻容式直流电压互感器适合直流谐波电压测量,而且测量误差小于0.2%,可达到10k Hz的频率带宽。
Harmonic phenomena analysis and control are significant aspects for ensuring normal operation of high voltage direct current（ HVDC） systems. An elaborate understanding of harmonic measurement must be developed to find the most suitable measuring method. Direct current voltage transformer（ DCVT） is an important apparatus to measure voltage in direct current transmission systems. This paper attempts to introduce and analyze the characteristics of the main components of resistive-capacitive voltage transformer such as coaxial cable,A / D and D / A converter,and optical coupler,for measuring harmonic voltage. The stray capacitance of voltage divider was analyzed in detail to determine its effects on the voltage transformer＇s frequency characteristic. The analysis indicates that selecting an appropriate resistor-shunt capacitance can reduce the influence of stray capacitance. Furthermore,the divider＇s non-ideal components were also analyzed and the analysis showed that choosing good resistors and capacitors could reduce the measurement error. Experiment results also showed that resistive-capacitive voltage transformer is quite suitable for harmonic voltage measurement with error less than 0. 2% and bandwidth up to 10 k Hz.
出处
《电工电能新技术》
CSCD
北大核心
2015年第3期54-60,共7页
Advanced Technology of Electrical Engineering and Energy
基金
电网安全与节能国家重点实验室开放基金资助项目
关键词
高压直流输电谐波
谐波电压测量
直流电压测量
直流阻容式电压互感器
阻容分压器
频率响应
HVDC harmonic
harmonic voltage measurement
DC voltage measurement
DC resistive capacitive voltage transformer
resistive capacitive voltage divider
frequency response
