Tag Archives: PI controller

Power Quality Improvement for Distribution Network by Design of Two Control Strategies for Active Power Filter (Published)

This paper introduces a design for two different control strategies (proportional integral (PI)-controller and Instantaneous Active and Reactive Power (PQ) method) based on hysteresis current control technique (HCCT) which are applied on shunt active power filter (SAPF) used in distribution system including of nonlinear load to achieve harmonics mitigation and reactive power compensation, where the presence of nonlinear load causes different disturbances and leads to poor power system quality, therefore shunt active power filter has been proposed to provides good harmonic compensation and limit the total harmonic distortion in distribution system to an acceptable values specified by power quality standard and finally get power quality improvement. Where the performance of shunt active power filter depends on the accuracy of the control theory, MATLAB / SIMULINK power system toolbox is used to simulate the proposed distribution system and simulation results are presented and discussed against two control method’s performance to showing the effectiveness of the control algorithm.

Keywords: APF, HCCT, PI controller, PQ, SAPF


Multivariable system is usually characterized with loop interactions which normally have deteriorating effect on closed loop performance. Thus, there is need to decouple the system for efficient performance of the multivariable feedback system. In this work, dynamic and static compensators were used to remove loop interactions. Inverse of the steady state gain was used as static compensator while dynamic compensator elements were obtained using feedforward design technique. These were applied to design feedback control system for Shell Heavy Oil Fractionator (SHOF) using Proportional integral (PI) control settings. PI controllers for the plant were tuned using Ziegler-Nichols, Tyreus-Luyben and PID modules built in MATLAB for different plant parameters. The closed loop system was implemented based on gain scheduling strategy. Good control performance was achieved using settling time, rise time and overshoot as performance metrics for the control strategy

Keywords: Compensators, PI controller, Shell heavy oil Fractionator (SHOF), gain scheduling, multivariable system