Application of the AFT technique for low-cost and accurate measurements

This paper deals with an evaluation of the use of the arithmetic Fourier transform (AFT) in fast and accurate measurement of the analyzed signal amplitude. The approach in the frequency domain is preferable to that in the time domain, owing to its ability to give information about a number of parameters in addition to the r.m.s. values of the voltage and current, such as the fundamental components, fundamental phase angles and harmonics. The disadvantage of using the usual FFT techniques, relevant to the large amount of computation involved (especially when the length of the analyzed sequencies is not a power of two), is reduced when the proposed AFT technique is used in the computation process. Then, using the proposed procedure, one can obtain a very fast, relatively low-cost, and accurate measurement with respect to that of the FFT. Several numerical results proved these interesting conclusions