基于数学形态滤波和Hilbert变换的电压闪变测量

随着电力系统中大容量冲击负荷的不断增加，配电网中的电压闪变也越发严重，因此需要对其进行检测和分析，为进一步的治理奠定基础。而IEC推荐的闪变测量方法只能给出闪变的统计性评价指标如短时闪变严重度和长时闪变严重度，此种指标无法说明闪变的具体参数特征。为此，文中给出了基于数学形态滤波和Hilbert变换的电压闪变快速测量计算方法。其中，基于数学形态学的滤波方法相比传统的数字滤波方法计算速度更快，更易于硬件实现，而且能够在保留电压闪变信号扰动特性的前提下有效地去除电压闪变信号中含有的尖峰脉冲、白噪声，高频噪声等干扰，将去噪后的信号进行Hilbert变换可准确地测出闪变的包络，为进一步测量电压闪变的有关参数奠定了基础。仿真试验证明了所提方法的有效性。

Voltage Flicker Detection Method Based on Mathematical Morphology Filter and Hilbert Transform

With the rapid increase of portion of large capacity arc furnace load in power system, voltage flicker has become a serious problem. In order to develop solutions to the problem, accurate and fast measurement of voltage flicker is required. But voltage flicker measurement method recommended by IEC can only provide statistical assessing indices such as short time flicker severity and long time flicker severity, which can't explain features of voltage flicker. A novel flicker detection method based on Mathematical Morphology (MM) filter and Hilbert transform is proposed in this paper. Compared to traditional digital filters, MM Filter has higher calculation speed and easier hardware realization, which can filter out impulses, white noises and high frequency noises contained in flicker signal and at the same time keep the original characters of flicker disturbances. Then to the filtered flicker curves, a track method based on Hilbert transform is adopted to get voltage flicker's envelope, which is the base of attaining relevant parameters of voltage flicker. Simulation experiments validate the proposed method's superior performance.