Active power filter for three-phase current harmonic cancellation and reactive power compensation

To address power quality problems in industrial power systems, a new control scheme for three-phase active power filter is proposed. The control scheme includes two functional modules such as a current harmonic cancellation module and a reactive power compensation module. The current harmonic cancellation module is based on a multiple adaptive feed-forward cancellation algorithm for selective current harmonic identification. The reactive power compensation module utilizes the measured voltage and the estimated fundamental current to calculate reactive power. After the above information has been calculated, the corrective current reference signals can be generated for the active filter. In this way, the two control functions are integrated together so that one active filter can accomplish two functions simultaneously. Simulation results under different operating conditions demonstrate that the proposed control scheme can successfully cancel harmonic current and compensate reactive power at the point of common coupling.