Optimal design of a robust FO-Multistage controller for the frequency awareness of an islanded AC microgrid under <i>i</i> -SCA algorithm
Prakash Chandra Sahu, Ramesh Chandra Prusty, Sidhartha Panda
Abstract
The article contributes a research work on optimal designing of a Fractional Order-Multistage PD/(1 + PI) controller (FO-Multistage) for controlling the frequency of an islanded AC Microgrid under various uncertainties. The renewable energy-based proposed Microgrid system is configured with the penetration of numbers of distributed generation (DG) systems. However, the large uncertainties and low inertia of most DG system result in fluctuations of frequency in islanded microgrid system. To maintain nominal frequency, the article proposes a robust FO-Multistage controller to constitute a secondary control loop in the microgrid system. An improved-sine cosine algorithm (i-SCA) is suggested to optimally design the robust FO-Multistage controller under various uncertainties. The system performance is also verified under stochastic model-generated wind and solar power uncertainties. The viability of the proposed approaches is demonstrated through a suitable comparative analysis over some conventional approaches. It has been investigated that the system performance has been improved gracefully with the proposed i-SCA-optimised FO-Multistage controller.