基于改进平方检测和新型K-N互卷积窗的闪变参数检测

传统的数字式闪变仪研制主要根据IEC闪变测量原理将各环节的模拟滤波器转换为数字滤波器来实现,但数字滤波器的效果受限于采样频率和变换方法的选取。提出利用解析模式分解改进传统平方检测法的滤波环节,准确提取电压闪变包络信号,构建新型K-N互卷积窗函数,推导基于新型K-N互卷积窗三谱线插值修正算法,据此提出基于改进平方检测法和新型KN互卷积窗的闪变参数检测方法,开发基于虚拟仪器的闪变参数检测平台。仿真实验结果表明,所提算法在单一频率调制、多频率调制、电网频率波动、含有叠加谐波及噪声干扰的情况下,均能有效实现闪变参数的准确检测,相较于传统检测方法,实现简单且具有更高的准确度。

Flicker parameters detection based on the improved square demodulation method and new K N mutual convolution window

The development of the traditional digital flicker meter is realized by converting the analog filter of each link into digital filter according to the flicker measurement principle provided by IEC. However, the effectiveness of the digital filter is limited by the sampling frequency and the transformation selection. To achieve accurate extraction of the voltage flicker envelope signal, the analytical mode decomposition is used to improve the filter link in the square detection method. A new K N mutual convolution window is proposed. The correction algorithm, which is based on the K N mutual convolution window and the three spectral line interpolation, is realized. The flicker parameter detection method based on improved square detection method and new K N mutual convolution window is proposed in this study. The flicker parameter detection platform based on virtual instrument is developed. Simulation experimental results show that the proposed algorithm can effectively realize the accurate detection of flicker parameters in the cases of single frequency modulation, multi frequency modulation, power grid frequency deviation, containing superposition harmonic interference and noise interference. This method is easy to realize and its accuracy is higher than the traditional detection methods.