Do I need to use a line reactor with VFDs to work with an Active Harmonic Filter?

All non-linear loads must have an input line reactor (minimum 3%) or a DC link choke to achieve the desired system performance. While an AHF can correct harmonics without line reactors, issues can occur if there is not sufficient impedance between an AHF and a load.

Using line reactors is also cost effective since reactors mitigate some of the harmonics and a smaller AHF can be deployed.