Contents I. Introduction
With the increase of harmonic distortion in modern distribution networks, due to the widespread diffusion of power electronics devices, the problem of harmonic emissions assessment and mitigation has become a very important issue [1]. To promote regulation strategies and incentives for harmonic mitigation and billing systems for sharing responsibility between customers and utilities for harmonic disturbances, it is necessary to have simple tools for evaluating harmonic pollution levels at the point of common coupling (PCC) as well as on the whole grid. The issue has been largely debated in scientific literature [2]–[12]. Sophisticated methods have been formulated to separate customers and utilities contribution to harmonic distortion, and to investigate the impact of single harmonic components. However, such methods are difficult to be implemented in practical measurement equipment used for billing purposes (i.e. the common smart metering platforms currently used in distribution networks, which have limited memory). On the contrary, simpler methods have been proposed, which allow indicating the prevailing source of disturbance upstream or downstream the PCC or the presence of a disturbing load.
