Harmonics measurement with a Modulated Sliding DFT algorithm on an FPGA platform

Effective harmonics estimation has become a key issue in power quality assessment. This paper deals with a DFT (Discrete Fourier Transform) based measurement technique, which can be easily employed to accurately determine the harmonic components of a distorted signal. The proposed method uses an mSDFT (Modulated Sliding DFT) algorithm and a Variable Sampling Period Technique (VSPT) to achieve a frequency adaptive mechanism. It provides (i) high degree of accuracy, (ii) structural/performance robustness, (iii) frequency adaptability, and (iv) requires no damping factor. The structural simplicity of the algorithm renders it suitable for a Field Programmable Gate Array (FPGA) implementation.