Modification of the Spectral Analysis Method for Measuring Power Parameters Based on the Application of Window Functions

Accurate spectrum measurement is one of the most important measurement tasks in the electric power grids. Knowledge of the complex spectrum allows to indirectly measure the vast majority of signal parameters. These include the parameters of electric power: active, apparent and reactive. The prevailing source of methodological error is the so-called “spectrum leakage” effect. The most common approach to suppress the spectrum leakage effect is the window function application. This approach allows using computationally efficient fast Fourier transform algorithms to obtain the signal spectrum. In this paper, we consider the application of the window function method to measure frequency, amplitude, initial phase and power parameters for the case of using rectangular and Hanning window. Interpolations of the spectrum for different numbers of spectrum samples are considered: one, two, three and five. By using MATLAB and Simulink, simulation models are proposed that allow evaluation of the effectiveness of the presented techniques.