This research presents compensation of current harmonic disturbance in power system network using
shunt active power filter. In this paper, harmonic extraction using Synchronous Reference Frame
Fundamental technique (SRFF) was investigated for three phase 3-wire system. It proposes a method
based on direct current measurement of load currents using a band pass filter at low cut off frequencies
to improve the filtering ability in highly contaminated loads. The proposed filter consists of second
order low pass and high pass filters cascaded together at suitable frequencies, estimated based on the
output of these units to mitigate the current harmonics. The performance of the system was simulated
in Matlab Platform and evaluated considering total harmonic distortion of the source current in a threephase
balanced network. The simulation results show the ability of the proposed tracking scheme to
accurately estimate harmonics.