环境因素对 CVT 谐波传变特性的影响研究

Study on the Influence of Environmental Factors on Harmonic Transfer Characteristics of CVT

为获取运行环境因素对电容式电压互感器(capacitor voltage transformer,CVT)谐波传变特性的影响,本文建立35 kV电容式电压互感器的高频等效模型,采用等效变换法进行传递函数的简化求解;在不同环境因素变化下,理论分析环境因素变化对CVT内部结构产生的影响。并基于Matlab仿真平台,仿真分析环境变化下CVT传变特性变化规律。发现环境温度和频率对CVT谐波传变特性都会产生影响,且对CVT的谐波传变比影响较大,温度主要影响CVT补偿电抗器电感值、主电容值、杂散电容值;频率偏移主要导致CVT输出偏移,从而影响CVT谐波传变特性。

For obtaining the influence of operation environment factors on the harmonic transfer character istics of capacitive voltage transformer( CVT), the high frequency equivalent model of 35 kV capacitive voltage transformer is set up, and the equivalent transformation method is used for simplified solution of transfer function. Under the variation of different environmental factors,the influence of environmental fac tor on the internal structure of CVT is analyzed theoretically. The variation law of CVT transfer characteris tics under environmental changes is simulated and analyzed on the basis of Matlab simulation platform. It is found that both ambient temperature and frequency can have influence on the harmonic transfer characteris tics of CVT and the influence on the harmonic transfer ratio of CVT is bigger. The temperature mainly af fects the inductance value,main capacitance value and stray capacitance value of CVT compensation reactor. The frequency shift mainly causes the output deviation of CVT,which affects the harmonic transfer characteristics of the CVT.