Three, Four and Seven Parameters Sine-fitting Algorithms Applied in the Electric Power Calibrations

Algorithms written in VBA with three, four and seven parameters sine-fitting are presented. They estimate values of frequency, amplitude, phase, offset, and RMS noise of sinusoidal waves. 4PSF algorithm applied on voltage and current signals from power source give two different frequencies. Application of 7PSF algorithm gives same frequency for both signals and about two times lower uncertainties for phase difference calculations than 4PSF algorithm. Abbreviations: 3PSF - three parameters sine-fitting; 4PSF - four parameters sine-fitting; 7PSF - seven parameters sine-fitting; DVM - digital voltmeter; DUT - device under test; and VBA - Visual Basic for Applications