Harmonic disturbances in networks, and their treatment

Electricity is generally distributed as three voltage waves forming a
3-phase sinusoidal system. One of the characteristics of such a system is
its waveform, which must always remain as close as possible to that of a
pure sine wave.
If distorted beyond certain limits, as is often the case on networks
comprising sources of harmonic currents and voltages such as arc
furnaces, static power converters, lighting systems, etc., thewaveform
must be corrected.

The aim of the present document is to provide a better understanding of
these harmonics problems, including their causes and the most
commonly used solutions.