Research Of Inter-harmonic Detection Algorithm Based On DSP

The inter harmonic detection algorithm is studied in this paper.Based on the traditional FFT detection,the windowed interpolation algorithm is adopted and the interharmonics detection of Hanning window ? Blackman window ? Blackman-Harris window?three Nuttall window?four Nuttall window is researched.The results of the test were compared and analyzed.The results show that the four Nuttall window interpolation FFT algorithm has the best detection accuracy.The recursive algorithm of Wavelet transform is used to detect inter harmonic and the results show that it has better performance for the detection of Inter harmonic.Hardware testing platform uses TMS320F2812 as the core chip,the three-phase voltage and three-phase current are collected,and the inter harmonics detection circuit is completed.By using C language programming,the algorithm transplantation is completed in the DSP hardware platform.The four Nuttall window interpolation FFT algorithm was applied to do the inter harmonic detection and the simulation.The experimental results show that the four Nuttall window has good sidelobe performance,and has a good effect to improve the spectrum leakage phenomenon.It has better detection performance by comparing with other algorithms.A recursive filter analysis method based on wavelet transform is applied.The algorithm transplantation in the DSP hardware platform has successfully been completed.The functional testing is completed.It can meet the requirements of accuracy and the needs of real-time.