电力系统测频算法比较

较全面地阐述了电力系统频率测量的重要意义和这些年来的研究成果。在初步分析了电力系统频率测量的实质的基础上,以测频主算法的数学原理为线索,对各种测频算法进行了分类和评述,包括数字滤波法中的DFT法,在表示信号频谱特性中具有较大优势,已成为目前电力系统频率测量的主导算法;小波变换法继承和发展了窗口Fourier变换时、频局部化的思想,同时又克服了窗口不随频率变化、没有离散正交基的缺点;其他算法如信号去调制法、过零相位比较法、解析函数法、函数逼近法、人工神经网络法等在实时性、准确性上则不如上述两种算法。建议性地提出了各种测频算法的适用场合,预期为有关人员进行电力系统频率测量时提供一定的参考。最后对电力系统频率测量的发展趋势提出了一些看法。

Comparison on Power System Frequency Measurement Algorithm

The importance and recent achievements in the field of power system frequency measurement are expounded in this paper.Firstly,the essence of the power system frequency measurement is assayed on the basis of signal observation model.Secondly the classification and comments of various kinds of frequency estimation algorithms are clarified by means of their mathematical features,including Discrete Fourier Transform,which has dominant position in expressing the characteristics of the signal spectrum,has become the leading algorithm in the field of power system frequency measurement;Wavelet Transform comes in for the idea of localizing time-spectrum of window Fourier Transform as well as overcoming the disadvantages of window Fourier Transform.It is also pointed that other algorithms,such as Removing signal modulate,Calculating zero-phase time,Analytic function,Function simulation,Artificial nerve network are not as good as the two algorithms above in the aspects of real-time performance and accuracy.The practicable conditions of the frequency estimation algorithms are suggested.In conclusion,the trend of the power system frequency measurement is demonstrated.