一种基于准均匀采样的电力谐波分析方法

针对电力谐波的准同步加窗分析法存在所用信号周期多、计算复杂和谐波泄漏分布不均匀等问题，基于准均匀采样提出了一种仅需1个信号周期特别适于单片机快速、准确实现的电力谐波分析方法。准均匀采样的时间离散误差不随连续采样而积累，在1个信号周期内取2的整数次幂个同步采样点，直接采用FFT算法即可实现谐波分析。基于信号的基波近似，并假设信号采样时的时间离散误差和幅值量化误差均服从均匀分布，对采用准均匀采样的电力谐波估计误差进行了分析。给出了基于准均匀采样电力谐波分析的算法和具体实现流程，流程中通过长整型变量对采样时间进行精确控制，算法简单高效。最后对准均匀采样谐波分析算法进行了仿真，结果表明基于通用单片机即可实现电力谐波的快速、准确分析。

A power harmonic analysis method using quasi-uniform sampling

There are problems of sampling in multiple signal periods, with high complexity and uneven harmonic leakage distribution in the quasi-synchronous windowing analysis method of the power harmonic. Thus a fast and accurate power harmonic analysis method suitable for MCU is proposed using quasi-uniform sampling. The time discrete error of quasi-uniform sampling does not accumulate with continuous sampling, so two integer power synchronous sampling points can be obtained in one signal cycle, and harmonic analysis can be realized directly with the help of a FFT algorithm. Based on the fundamental component approximation of the signal and assuming that the time discrete and amplitude quantization errors of signal sampling obey a uniform distribution, the power harmonic estimation error using quasi-uniform sampling is analyzed. The algorithm and specific implementation process of power harmonic analysis are given. In the process, the sampling time is accurately controlled by long integer variables, and the algorithm is simple and efficient. Finally, the quasi-uniform sampling harmonic analysis algorithm is simulated. The results show that fast and accurate power harmonic analysis can be realized based on a general purpose MCU. This work is supported by the National Natural Science Foundation of China (No. 61871387).