AUTHOR=Luo Ke , Jiao Yingying , Zhu Jiawei 

TITLE=Perturbation Observer Based Fractional-Order Control for SMES Systems Based on Jellyfish Search Algorithm

JOURNAL=Frontiers in Energy Research

VOLUME=Volume 9 - 2021

YEAR=2021

URL=https://www.frontiersin.org/journals/energy-research/articles/10.3389/fenrg.2021.781774

DOI=10.3389/fenrg.2021.781774

ISSN=2296-598X

ABSTRACT=Electric energy storage system (EESS) is considered as an efficient and promising tool to alleviate the power imbalance of grid-connected micro-grid with distributed generation (DG). This work develops a perturbation observer based fractional-order control (POFOC) strategy for superconducting magnetic energy storage (SMES) system. Initially, a high-gain state and perturbation observer (HGSPO) is designed for reliable estimation of the combined impact of SMES’s nonlinearities, parameter uncertainties, unmodelled dynamics, and external disturbances. Then, the storage function of a SMES system is designed, which takes favorable terms into serious consideration to sufficiently utilize SMES system’s physical properties. Moreover, a fractional-order control framework is applied for complete compensation for the estimated perturbation and adopted as the attached input to boost its dynamical responses. Furthermore, a newly proposed jellyfish search algorithm (JSA) is utilized to realize optimization and tuning of control gains of the developed strategy, upon which high-quality global optimum can be obtained to ensure prominent controlling performance. Case studies, e.g., active power and reactive power supply and system restoration capability after faults effectively validate the effectiveness and reliability of POFOC strategy compared with traditional PID control.