A novel scaling factor based fuzzy logic controller for frequency control of an isolated hybrid power system

Highly intermittent power, generated by wind energy in an isolated hybrid power system (IHPS), results in severe frequency and power fluctuation. The aim of this paper is to carry out a comparative study of scaling factor (SF) based fuzzy logic controller (FLC) (SF-FLC), SF-FLC with proportional-integral (PI) (SF-FLC-PI) controller, SF-FLC with proportional-derivative (PD) (SF-FLC-PD) controller and SF-FLC with proportional-integral-derivative (PID) (SF-FLC-PID) controller for deviation in frequency and power of an IHPS model. The undertaken model of IHPS for this study embraces a diesel engine generator, a wind turbine generator and an energy storage device (for instance, capacitive energy storage). Optimal tuning of the different tunable parameters considered for suppressing the deviation in frequency and power of IHPS model owing to alteration in load demand has been carried out by quasi-oppositional harmony search (QOHS) algorithm. The obtained results demonstrate minimum deviation in frequency and power may be realized by practicing the proposed SF-FLC-PID controller for the considered IHPS model. Robustness and non-linearity investigation have been also executed for the proposed SF-FLC-PID controller based configuration of the studied IHPS model. It is revealed that the proposed SF-FLC-PID controller is very much robust in nature and takes care of non-linearity very well while QOHS algorithm is adopted.