A Fractional Order PI (FOPI) Controller Design For Shunt Active Power Filter To Improve The Power Quality

In this article, a Fractional Order Proportional Integral (FOPI) controller based shunt active power filter (SAPF) is proposed. The FOPI controller is designed to have a constant voltage of the DC-Link of the SAPF which is used for the elimination of harmonics and there by to improve the power quality. To design the FOPI controller, phase margin, gain crossover frequency and velocity error constant are taken as desired specifications. For harmonic current extraction and gate signal generation, instantaneous active and reactive power (P-Q) approach and pulse width modulation technique (PWM) have been used. In order to show the effectiveness of the proposed FOPI controller in maintaining the a constant voltage and in eliminating harmonics thereby improving the power quality of the system, SAPF model is developed in MATLAB/SIMULINK and the effectiveness of the designed FOPI controller is analyzed. The results obtained with FOPI controller illustrates that the FOPI makes the system to have a the constant voltage of the DC-Link and compensates the harmonic components present in the system.