An Improved Harmonic Detection Method for Power Quality Based on Hybrid Convolution Interpolation

In order to suppress the spectrum leakage and fence effect caused by fast Fourier change, a new hybrid convolution window is constructed by combining the Hanning window with narrow main lobe and the four fifth-order Nuttall Windows with fast fading sidelobe. In addition, four-line interpolation is used to obtain the correction formulas of amplitude, frequency, phase and other parameters by polynomial fitting to solve the fence problem. This hybrid convolution window four-line spectrum interpolation harmonic detection method can realize the detection and analysis of complex signals in MATLAB environment. The proposed algorithm in this paper is compared with the single-window interpolation algorithm, which verifies the ability of the proposed algorithm to improve the harmonic detection accuracy.