Algorithm for measurement and processing of results from total harmonic distortion calibration of power quality analyzers by using standard periodic non-harmonic signals

The approach to calibrate the coefficient of total harmonic distortion of power quality analyzers using reference standard non-harmonic waveform signals, instead of the traditionally used set of harmonic signals is considered in [1]. Using a reference calibrator, square, triangular, saw-shaped signals and a truncated sine wave signal are generated in series, which provide setting of appropriate reference values of the total harmonic distortions for which the analyzer is calibrated. In the present work, a computer-based automation system and algorithm for calibration of Power Quality Analyzer are proposed by THD. The algorithm performs the sequence of operations for control of the reference calibrator and the calibrated analyzer, setting reference values of THD of the voltage/current from the calibrator, performing multiple measurements at the calibration point, measured results are extracted from the analyzer and their processing and an estimate of the actual value of the measured THD values and an estimate of the extended uncertainty is obtained at the analyzer calibration point.