复杂电能信号谐波时频域特征分析及其对电能计量影响

为准确分析复杂电能信号谐波时频域特性对电能计量的影响，提出了一种零值搜索-短时傅里叶变换时频域电压、电流信号幅度和相位分析算法，利用信号波形过零特征，自适应调整短窗傅里叶变换的时域窗宽，解决了电网频率波动导致的相位累积效应对相位分析的影响，算法的幅值分析误差为10-3、相位分析误差小于1°；建立了复杂电能信号时频域数据表征模型和4类时频域全局化特征矩阵提取算法，解决了时频域特性表征与提取的问题；以典型非线性动态负荷中频炉为分析案例，分析给出了其4类时频域全局化特征，并建立了畸变波形动态电能测试信号特征模型，通过辅助实验验证了4个时频域全局化特征对电能表动态超差的影响，提出了对国际和国内标准修改的建议。

Analysis of time-frequency domain characteristics of harmonics of complex energy signals and their influences on energy measurement

To accurately analyze the impact of complex electrical energy signal time-frequency characteristics on electric energy metering, the zero search-short-time Fourier transform(ZS-STFT) time-frequency domain voltage and current signal amplitude phase analysis algorithm is proposed, which adaptively adjusts the time domain window width of short-time Fourier transform(STFT) by using the signal waveform zero crossing feature, which solves the influence of phase accumulation effect caused by power grid frequency fluctuation on phase analysis. The amplitude analysis error of the algorithm is less than 10-3 and the phase analysis error is less than 1°. A time-frequency domain data representation model for complex power signals and four types of time-frequency domain globalize matrix extraction algorithms are established, which solves the problem of time-frequency domain characteristic characterization and extraction. Taking a typical nonlinear dynamic load intermediate frequency furnace as an analysis case, four types of time-frequency domain globa-lize are given by analysis. In addition, a distortion waveform dynamic energy test signal feature model is established. The influence of the four globalize of the time-frequency domain on the dynamic error of the energy meter is verified by auxiliary experiments, and suggestions for international and domestic standards are put forward.