Uncertainty analysis of power ratio parameters for harmonic emission assessment in power systems

To promote regulation strategies and incentives for harmonic mitigation, simple tools are needed for evaluating harmonic pollution levels at point of common coupling (PCC), as well as on the whole grid. Starting from IEEE Std. 1459-2010 approach [1] and the common concept of power factor correction, in [2] the authors have presented a preliminary study, aimed at investigating the possibility of using power ratio parameters for harmonic emission assessment. Being the formulation of IEEE Std. 1459 power quantities and related power ratio indicators very simple, the proposed indicators measurement can be easily integrated in common measurement instruments, thus allowing easily the assessment of harmonic emissions and related billing/incentives strategies implementation. In this context, it is important to investigate the measurement uncertainty impact on the evaluation of considered power ratios (both those defined in IEEE Std. 1459 and the new proposed ones) [2]. To this aim, the measurement of the considered parameters has been implemented on a PC-based sampling wattmeter. Starting from the instrumentation accuracies and the correlation analysis, combined standard uncertainties of power ratio indicators have been evaluated and a comparison has been made between IEEE Std. 1459 indicators and the newly proposed ones.