基于改进能量算子和六项余弦窗频谱校正的电压闪变包络参数检测

Voltage flicker envelope parameter detection based on improved energy operator and six-term cosine window spectrum correction

随着新能源和电力电子技术的广泛发展与应用,当前电网电压波动与闪变问题日趋严重。针对电压闪变参数的准确检测和评估,提出基于改进能量算子和六项余弦窗三谱线改进FFT的电压闪变包络参数检测方法。该方法与传统能量算子相比,无需平方根运算,计算速度更快、实时性更好。基于推导出的闪变校正系数使其在基波频率波动及各类谐波等电网干扰情况下的准确度和稳定性均显著提高,并搭建基于PXI+Lab VIEW架构的检测平台进行测试。仿真实验和实测结果证明:在分别含有单一调幅波调制、多频率调幅波调制、电网基波频率变动、含有各类谐波和白噪声干扰时,所提检测算法相比传统能量算子稳定性好、准确度更高,可有效实现电压闪变参数的在线检测与准确分析。

With the rapid development and application of new energy and power electronics technologies,the current grid voltage fluctuations and flicker problems are becoming more and more seriously.Aiming at the accurate detection and evaluation of voltage flicker parameters,a method for detecting voltage flicker envelope parameters based on improved energy operator and six-term cosine window three-spectral line interpolation is proposed.Compared with traditional energy operator,this method does not need square root operation,and has faster calculation speed and better real-time performance.The accuracy and stability of the system in the case of fundamental wave frequency fluctuation and various harmonics are improved by the flicker correction coefficient.A detection platform based on PXI+LabVIEW architecture is built and tested.The simulation and experimental results show that the detection algorithm is more stable and accurate than the traditional energy operator when it contains single amplitude modulation,multi-frequency amplitude modulation,fundamental frequency fluctuation,harmonic,inter-harmonic and white noise interference respectively.And the real-time online detection and accurate analysis of voltage flicker parameters can effectively be realized.