Metering and tariffs for harmonics

The growing and increasingly important sources of harmonic currents (and the resultant voltages) in electrical distribution systems are: fluorescent lighting; diode rectifying circuits; thyristor controlled circuits; and induction motor control using IGBTs. The harmonic currents generated by these nonlinear loads produce numerous undesirable effects. There is now a widespread view that the generation of harmonic currents must be regulated, not only to ensure that customers pay for the energy they use, but also to ensure quality of supply to other customers in a market where quality control is steadily becoming a statutory requirement. Two approaches in this direction are described by the author