Implementation of Proportional-Integral-Observer Techniques for Load Frequency Control of Power System

This paper presents the implementation of Proportional-Integral-Observer(PI-Observer) based state feedback control for Load Frequency of single area isolated power system model. The general application of PI-Observer has been realized in areas of robotic and mechanical system. The PI-Observer is used to estimate both the original states and the unknown inputs generally disturbances, modeling errors or the other non-linearities present in the system. The estimation error of the PI-Observer is gradually reduced by the proportional and integral feedback loop that appreciably improves the observer dynamics. A single area linear power system model is taken as a test case to implement the proposed methodology which is then compared with full state Luenberger observer based state feedback control for load frequency control of power system. MATLAB/SIMULINK is extensively used for modeling & simulation of power system and observer. The dynamic responses are compared and discussed on the basis of error dynamics, system states, peak overshoot and settling time. Lastly it was found that response of PI-observer based state feedback control scheme is quite appreciable as compared to Luenberger observer based state feedback schemes.