A DAQ-based sampling wattmeter for IEEE Std. 1459-2010 powers measurements. Uncertainty evaluation in nonsinusoidal conditions

•The proposed wattmeter is based on commercial data acquisition boards.•A correction stage is implemented to improve the accuracy of the instrument.•The instrument uncertainty is evaluated in accordance with the GUM.•An experimental correlation analysis is carried out for the uncertainty evaluation.•The wattmeter can be used for of transfer standards under non sinusoidal condition.

This paper presents the evaluation of the metrological performances of a DAQ-based sampling wattmeter (DAQ-SW) for the measurement of IEEE Std. 1459-2010 power quantities in non-sinusoidal conditions. The instrument makes use of two commercial data acquisition (DAQ) boards, a non-inductive current shunt, a personal computer and a commercial software for data processing. Starting from the results of an experimental characterization of the two instrument channels with non-sinusoidal voltages and currents and a correlation analysis, the combined standard uncertainties of IEEE Std. 1459-2010 quantities are evaluated, following the approach of the ISO Guide to the Expression of Uncertainty in Measurement (GUM).