Active compensation of harmonics in industrial applications

In industrial low and medium voltage mains, passive filters and PFC capacitors have traditionally been used to improve the supply quality. However, they cannot be rated only for the loads being compensated. They are affected by harmonic currents from other non-linear loads or by harmonics from the power system [1]. Compared with passive element compensators, an active harmonic compensator (AHC) can be used to improve the supply quality without worrying about all the problems associated with applying passive elements.