Abstract:To realize high-accuracy measurement of harmonic energy in complicated industry field, a kind of harmonic energy measurement method based on wavelet packet decomposition and reconstruction algorithm is presented. The wavelet packet decomposition and reconstruction algorithm and the extraction method of harmonic signal based on this algorithm are introduced. The calculation expression of harmonic power and the principle of harmonic energy measurement are listed. The simulation analysis of harmonic energy measurement use db42 wavelet function, 50Hz as fundamental frequency, 2-layer wavelet packet transform, simulation input signal about forty fundamental periods and 800Hz for sampling. The simulation results of active energy and reactive energy of harmonic in steady or unsteady state demonstrate feasibility and accuracy of this algorithm. Three-phase harmonic energy measurement device based on VI technology developed on the basis of this algorithm realizes active energy and reactive energy measurement of each time harmonic. The accuracy class of fundamental energy measurement is up to 0.2S and the harmonic energy measurement fulfills the accuracy requirements of the A class harmonic measurement.
滕召胜, 罗志坤, 孙传奇, 高云鹏, 唐求. 基于小波包分解与重构算法的谐波电能计量[J]. 电工技术学报, 2010, 25(8): 200-206.
Teng Zhaosheng, Luo Zhikun, Sun Chuanqi, Gao Yunpeng, Tang Qiu. Harmonic Energy Measurement Based on Wavelet Packet Decomposition and Reconstruction Algorithm. Transactions of China Electrotechnical Society, 2010, 25(8): 200-206.
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