Desynchronized Processing Technique for Harmonic and Interharmonic Analysis Based on Cosine Window Interpolation

作者：Xu, Lin^*; Han, Yang; Yao, Gang; Zhou, Li Dan; Khan, M M; Chen, Chen; Pan, Jun Min

来源：International Review of Electrical Engineering, 2009, 4(5): 943-956.

• Fast Fourier Transform
• Harmonic and Interharmonic detection
• Leakage effect
• Synchronization
• Power system
• Signal processing
• Frequency deviation

The Fast Fourier Transform (FFT) suffers from the deficiency of leakage effect for the harmonic and inter-harmonic analysis of electric signals. in order to overcome the leakage effect of FFT algorithm, a new desynchronized signal processing technique is proposed, which is based on poly-item cosine window (CW) interpolation. The proposed technique is consisted of a double-stage signal processing procedure. In the first stage, the harmonic components are accurately estimated via cosine window interpolations in the frequency domain and the estimated signal is subtracted from the original signal in the time domain. In the second stage, inter-harmonic components are accurately obtained via the same interpolation without the spectral leakage problems. Since the procedure does not require synchronization, a fixed sampling frequency can be utilized to simplify the data acquisition process. Meanwhile, the computational burden is remarkably reduced due to the direct utilization of the FFT on the acquired sampling signal. Extensive simulation results are provided to verify the validity and effectiveness of the proposed algorithm, which reveals that the frequencies, amplitudes and phase angles of the harmonics and the inter-harmonics are accurately calculated, even under significant fundamental frequency deviations in the input signal. Moreover, the proposed technique is found to have overwhelming advantages in terms of the improved estimation accuracy and reduced computational burden compared to the existing unsynchronized sampling techniques in literature.

• 出版日期2009-10
• 单位上海交通大学