The Research Of Improved Dual-Windowed Interpolation Harmonic Detection And Hybrid Active Power Filter Simulation

With the rapid development of power electronics technology in the modern life, the problem of power system harmonic pollution is growing serious. In the research of power system harmonics, hybrid active filter is the main research directions and an effective treatment of harmonic pollution, The accurate harmonic measurement provides an important scientific basis for the harmonic compensation and inhibition, is the key link in the study of hybrid active power filter. The harmonic analysis method for the fast Fourier transform is widely used because of its easily achievement.But,the detected Harmonic parameters will be affected by spectrum leakage and Hurdle Effect in the aspects of accuracy while using FFT directly under non-coherent sampling process in the course of conducting the harmonic analysis, which leads to a bad performance.Therefore, it is of great theoretical and practical significance to research new window function and implement novel FFT-based methods for HAPF.In this paper, all the studying are based on the three phase hybrid active power filter. Firstly, I introduce the definition of harmonic, generate research status and development trends of the principle of harmonic detection method and hybrid active power filter. Comparatived the factors that affect the accuracy of the FFT harmonic measurement to study the problems it caused and solutions, Lists several commonly used window function, through the study of window function time domain and frequency domain properties to propose window function selection principle. Secondly, this paper built a improved harmonic detection method which based Triang self-convolution window and Hanning self-convolution window from the point of improved window function to suppress spectral leakage. The SCW is constructed by self-convolutions of the window in time domain, with the convolution increase in numbers, its spectral leakage suppression are also rapidly increasing. After simulating the window function, it proves that self-convolution window is better than the commonly used windows in amplitude and frequency characteristics. The improved harmonic analysis method based on the SCW is presented to solve the problem of FFT.Finally, by using the Matlab/Simulink software to simulate the system modeling of HAPF. The simulation results show that the SCW interpolation detection harmonic analysis can detect the harmonic current, and effectively compensate harmonic current for the power system waveforms with serious distortion, and the harmonic distortion rate is reduced. Theoretical analysis and simulation results verify that the study of the hybrid active power filter is effective and feasible.