The Hanning self-convolution window (HSCW) is proposed in this paper. And the phase difference correction algorithm based on the discrete spectrum and the HSCW is given. The HSCW has a low peak side lobe level, a high side lobe roll-off rate, and a simple spectrum representation. Hence, leakage errors and harmonic interferences can be considerably reduced by weighting samples with the HSCW, the parameter estimation by the HSCW-based phase difference correction algorithm is free of solving high order equations, and the overall method can be easily implemented in embedded systems. Simulation and application results show that the HSCW-based phase difference correction algorithm can suppress the impacts of fundamental frequency fluctuation and white noise on harmonic parameter estimation, and the HSCW is advantageous over existing combined cosine windows in terms of harmonic analysis performance.hanning self-convolution window, FFT, phase difference, spectral leakage, frequency fluctuationThe accurate dynamic estimation of signal parameters has been a hot topic in the field of signal processing [1] . The estimation can provide an information basis for power measurment [2] , fault diagnosis [3] , electrical harmonic compensation [4] , and orthogonal frequency-division multiplexing [5] . Compared with wavelet transforms, the fast Fourier transform (FFT) is more computationally efficient and easier for implementations in embedded systems such as DSP and ARM, and is by now the most widely used in various signal parameter estimation algorithms [6,7] .For dynamic signals, it is difficult to achieve strict synchronous sampling even if frequency tracking technologies are adopted [8,9] . When using FFT to estimate signal parameters with asynchronous sampling, estimation error due to the spectral leakage and picket fence effect introduced by the asynchronous sampling and signal cutoff is relatively large [10] . Various kinds of windows, e.g., the rectangular window [11] , the Hanning window [12] , the Hamming window [13] , the Blackman window [14] , the Blackman-Harris window [15] , the RifeVincent window [16] , the Nuttall window [17] , the polynomial windows [18] , the flat-top window [19] , and the rectangular convolution window [20] , have been proposed and used in the windowed interpolation FFT algorithms, and they can in some degree suppress spectral leakage and increase the accuracy of the signal parameter estimation. The use of the FFT algorithms with dual-spectrum-line [7,12,14] or multi-spectrum-line [6,8] interpolation based on high order combined cosine windows in fundamental and harmonics parameter estimation involves, however, solving high order equations, which is computationally expensive [21][22][23] . Different approaches have been proposed to solve the problem. Yang, Ding et al. gave a discrete phase difference correction algorithm suitable for all kinds of symmetrical windows, which can calculate signal parameters without relying on the expression of the window spectral function [24] . Yang et al. proposed ...