基于非迭代多点插值DFT的谐波电能计量算法

Harmonic Energy Metering Algorithm Based on Non- Iterative Multipoint Interpolation DFT

在电网信号普遍存在谐波的情况下,为了满足相关标准规定的电能计量准确度和稳定性的要求,需要更精确地估计电网信号谐波参数。在广义加窗离散傅里叶变换和频谱插值校正方法基础上,采用快速傅里叶变换(FFT)和最大衰减旁瓣窗方法,对准确估计谐波参数进行了研究。在充分考虑并消除了与共轭分量相关的参数对估计结果影响的同时,使用了插值离散傅里叶变换(IpDFT)算法。根据谐波标准IEEE STD 1459功率定义,进行谐波电能准确计量的仿真计算。仿真结果表明,该算法可以成功地用于短时间情况下的快速、准确谐波电能计量,避免了常用的多点线性插值方法带来的累积误差,可应用于高精度动态负荷谐波电能计量,较以往其他计量算法具有更广的适用性。

Harmonics commonly exist in the power grid signal,in order to meet the requirements of accuracy and stability of the energy metering specified by relevant standards,it is necessary to estimate the harmonic parameters of the grid signal more accurately.Based on the generalized windowed discrete Fourier transform and spectral interpolation correction method,the fast Fourier transform(FFT) and the maximum attenuation sidelobe window method are used to accurately estimate the harmonic parameters.The influence of the parameters related to the conjugate component on the estimation result is fully considered and eliminated,and the algorithm is better than the multi-point iterative IpDFT algorithm based on the finite difference of the interpolation point.According to the harmonic standard IEEE STD 1459 power definition,the simulation calculation of harmonic energy accurate metering is carried out.The simulation results show that the proposed algorithm can be successfully used for fast and accurate harmonic energy metering in short-time situations,avoiding the cumulative error caused by the commonly used multi-point linear interpolation method,and can be applied to high-precision dynamic load harmonic energy metering.It has wider applicability than other metering algorithms in the past.