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针对非稳态电力信号傅里叶谐波分析中频谱泄露所导致测量误差较大的问题,提出一种基于准同步序列重构的非稳态电力谐波分析方法.首先在频域上对原始采样信号进行50 Hz的频移,经过sinc滤波器滤除谐波分量,采用移频角差法求得基波频率偏移量;依据计算的基波频率,再通过三次B样条插值重构原始采样信号;最后利用全相位FFT有较优抑制频谱泄露的性能,对重构后的准同步序列进行谐波分析,确定每一个谐波成分参数,实现谐波参数的准确测量.试验表明,该算法能有效检测非稳态信号的基波频率大小,实现非稳态下电力谐波信号的高精度检测,实验平台验证了方案的可行性.“,”Focusing on the problem of large measurement error that caused by spectrum leakage in Fourier harmonic analysis of non-stationary power system,a non-stationary power harmonic analysis method based on quasi-synchronous and sequence reconstruction algorithm was proposed.Firstly,the original sampling signal were moved 50Hz in frequency domain,the harmonics were filtering through SF,fundamental frequency was detected under the method of frequency shift and angular difference;and then,cubic B spline was used to reconstruct the original sampling signal;finally,every harmonic component could be accurately determined under the reconstructed quasi-synchronous sequence,which make use of the great performance of suppress spectrum leaks in all-phase FFT.Experiment results show that the proposed algorithm is suitable for the fundamental frequency and harmonics detection in the power system under non-stationary situations,and the feasibility of which is verified by the application in experimental platform.