本文提出一种基于间谐波测量的闪变值计算方法.该方法首先从电压畸变信号的角度提出了“AM-间谐波对”和“PM-间谐波对”的概念,由此区分引起闪变的调幅波和一般间谐波;然后以IEC61000-4-7推荐的采样窗口长度和形状为前提,用一种非同步采样下的奇数频点插值修正法测量电压信号中各频率分量的具体参数；根据信号转化等式,结合闪变最大觉察频率范围,估计闪变信号参数；根据IEC闪变仪原理,求出各个频率分量引起的瞬时闪变视感度以及闪变信号总的短时间闪变水平值.与平方法比较,仿真算例和现场采集的电孤炉启动过程中的电压信号实例验证了本文方法的准确性和可行性.%This paper proposed a new method to calculate the voltage flicker values based on inter-harmonics meas urement. In this method, the concept of "AM-inter-harmonic pair" and "PM-inter-hannonic pair" are proposed to distinguish the modulation wave and general inter-harmonics which will cause flicker based on the voltage distortion theory. The proposed method obtains the parameters of each frequency component using the odd points interpolation correction method, which reducing the leakage at interpolating, based on the specified signal processing recommen dations by IEC61000-4-7. Considering the voltage flicker perceptible frequency range and the signal transform e quations, we can estimate the parameters of flicker signal. According to the theory of IEC flicker meter, we can calculate the instantaneous flicker sensation level caused by each frequency component or the total flicker signal. Compared with the square method, the simulation example and the field data of an electric arc furnace voltage sig nal demonstrate the accuracy and feasibility of this method.
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