Real-time signal frequency analysis in variable speed drives using the sparse fast Fourier transform (sFFT)

This paper investigates the implementation and the use of the sparse fast Fourier transform algorithm in the converter control of a variable speed drive. The algorithm is proposed due to the reduction in computational complexity compared to the conventional fast Fourier transform for the special case of sparse signals. After discussing the theory and a simulation model, experimental results obtained using a field programmable gate array (FPGA) implementation are presented, showing the effectiveness of the proposed solution.