电容式电压互感器(capacitor voltage transformer,CVT)在66kV及以上电网的广泛应用,对其谐波传递特性研究日趋重要。本文运用黑箱理论并结合CVT电气构造特点,搭建一种可以获取CVT谐波传递特性的试验电路。从电容分压器结构和电介质材料角度研究电介质极化与外电场频率关系,确定在50~2500Hz范围内频率变化不影响电容分压器分压比。再整体分析试验电路,建立试验电路网络阻抗模型,仿真不同分压点电压之间关系,并通过试验进行相互验证,论证测量CVT谐波传递特性的试验电路的正确性。为测量CVT谐波传递特性提供科学规范的测量方法,对CVT谐波传递非线性机理深入研究具有重要意义。
英文摘要:
With the capacitor voltage transformer being widely used in 66kV and above power grid, the research about harmonic transmission characteristic becomes more and more important. A circuit measured accurately CVT harmonic transmission characteristic is built according to black box theory and the characteristics of CVT electrical structure in this paper. To research the relationships between dielectric polarization with external electric field frequency from the perspective of capacitive voltage divider structure and dielectric materials and get the conclusion that frequency change does not affect the capacitive voltage divider ratio within 50 ~ 2500 Hz. Overall analysis about test circuit is made to get impedance network mode of the test circuit, and research the relationship among the different partial voltage point by simulation , and demonstrates the measurement of CVT harmonic transmission characteristics of the correctness of the test circuit. A scientific and standardized method of measurement is provided for accurate measurement of CVT harmonic transmission characteristics, and it provides the CVT transmission nonlinear harmonic wave of further research is of great significance as well.
