A study on the identification of major harmonic sources in power systems

Power system transmission and distribution utilities strive to ensure that the voltage harmonic distortion planning levels are maintained by limiting the harmonic currents injected by the loads. With large customers assessment of the harmonics contributed is carried out at the point of common coupling (PCC). Determination of the contribution to the overall harmonic distortion at the PCC by the major customer is a complex task as it is dependant on aspects such as supply system configuration, associated loads and background harmonics for which the supply authority is responsible. This paper reviews some of the methods that have been proposed to identify the harmonic contribution by a load and reports on a preliminary simulation study in relation to a highly simplified practical situation.