Harmonic compensation apparatus and methods with three level inverter

摘要

A parallel connected active harmonic compensator is disclosed having a three level inverter (14) to provide the power stage for supplying or drawing current to or from a line of an AC power distribution system to compensate for harmonics drawn by a load (RL) supplied by the line. The active harmonic compensator compensates for one or more harmonic components by deriving a control signal which is substantially devoid of the relevant harmonic components, generates predetermined boundaries relative to the control signal and used the boundaries to control the inverter switches (14) to supply or draw current to or from the line to remove the relevant harmonic components.