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非同步采样时,含有邻近间谐波的基波信号进行短时傅里叶变换时,基波、间谐波和各自负频率成分间会产生严重的频谱干扰.因此,为了准确提取并测量混叠频谱中的基波成分,该文提出基于滑窗频谱分离的基波参数测量方法.首先建立多频率信号模型,并基于短时傅里叶变换推导出频谱分离算法,分离出基波和干扰的频率分量,最终计算出基波参数.该文在电压波动、频谱混叠等多种工况下进行算法验证,结果表明,所提方法能够准确地提取基波成分,并兼具较高的时间分辨率和参数测量精度,且具有一定的抗噪性.同样,所提方法也适用于谐波和间谐波的识别和测量.“,”The severe spectrum interferences could occur among fundamental wave,interharmonics and their negative frequency components when the fundamental signal which contains adjacent interharmonics was analyzed by short-time Fourier transform (STFT) under asynchronous sampling condition.Therefore,in order to decompose and measure the fundamental component of the aliasing spectrum,a new fundamental parameter estimation method based on sliding-window spectrum separation and measurement (SSSM) algorithm was proposed.Firstly,multiple frequency signal model was established,and the spectrum separation algorithm was deduced by short time Fourier transform.Then,fundamental component and other components are separated,and the fundamental parameters can be calculated.The method has been verified via a variety of cases,such as voltage fluctuation and spectrum aliasing,the results show that the proposed method can accurately extract the fundamental component with high temporal resolution and parameter measurement accuracy,and has the ability of anti-noise to some extent.In addition,the method can also be applied to identification and measurement of harmonics or interharmonics.