Harmonic Mitigation Analysis of Pi and Fuzzy Logic Based Shunt Active Power Filters For Different Non-Linear Loads
In modern electric power system, harmonic contamination due to the intensive use of power converters and
other non-linear loads in industry and by consumers become a serious and a harmful problem. The non-linear loads draw
non-sinusoidal current when sinusoidal voltage is applied and hence cause harmonic currents. The presence of harmonics in
the power line can cause undesirable effects like greater power losses in distribution, noise problems in communication
systems and failure of operation of electronic equipments which have higher sensitivity because of the inclusion of
microelectronic control systems. So, the harmonic current need to be suppressed to enhance the power quality since it cannot
contribute to active power. The main objective of this paper is to provide a solution to harmonic current problem by
developing a PI and Fuzzy logic controllers based shunt active power filter and compare the performance controllers when
connected to two different loads namely rectifier and DC motor load. Matlab R2010b /simulink power system toolbox is
used to simulate the proposed system The total harmonic distortion and the power factor are obtained for three cases -
without filter , shunt active power filter with PI and Fuzzy Logic controller for both the loads under balanced source
voltage conditions. The results obtained by simulation show the effectiveness and the superiority of shunt active power
filter; with Fuzzy Logic controller compared to PI controller for both load conditions.
Index Terms— DC link voltage, Fuzzy Logic Controller, Harmonics, Proportional Integral Controller, Power Quality,
Shunt Active Power Filter, Total Harmonic Distortion.