Harmonic Sources Modeling and Characterization in Modern Power Systems: A Comprehensive Overview

The future of power systems is moving towards a greater use of renewable energy sources and a higher proportion of power electronic devices. However, this has led to an increase in power quality issues that can seriously affect the stable operation of power systems. One key aspect of evaluating power quality of the grid is analysing harmonics and their sources. There are several challenges in understanding and controlling harmonics, including modelling the sources of harmonics, tracing them, and controlling their impact. This paper presents a comprehensive review on the common models of harmonic sources in modern power systems, and provides insight into the circuit mechanisms, mathematical models, and operational processes of these sources. It also examines the harmonic characteristics of various sources in typical operating scenarios, involving typical residential power load, electric vehicle charging scenario, frequency conversion speed regulating device, renewable energy generation scenario, electric arc furnace load and electric locomotive load, and offers a summary of typical harmonic source equipment. Additionally, this paper looks ahead at the future and development directions of harmonic analysis and control in the context of modern power systems. This work can be used as a guide to improve the understanding of harmonic distortion in modern power systems and to develop methods for mitigating its negative effects on power quality and system stability.