Adaptive fractional-order PID control for VSC-HVDC systems via cooperative beetle antennae search with offshore wind integration

Abstract

Since the voltage source converter based high voltage direct current (VSC-HVDC) systems owns the features of nonlinearity, strong coupling and multivariable, the classical proportional integral (PI) control is hard to obtain content control effect. Hence, a new perturbation observer based fractional-order PID (PoFoPID) control strategy is designed in this paper for (VSC-HVDC) systems with offshore wind integration, which can efficiently boost the robustness and control performance of entire system. Particularly, it employs a fractional-order PID (FoPID) framework for the sake of compensating the perturbation estimate, which dramatically boost the dynamical responds of the closed-loop system, and the cooperative beetle antennae search (CBAS) algorithm is adopted to quickly and efficiently search its best control parameters. Besides, CBAS algorithm is able to efficiently escape a local optimum because of a suitable trade-off between global exploration and local exploitation can be realized. At last, comprehensive case studies are carried out, namely, active and reactive power tracking, 5-cycle line-line-line-ground (LLLG) fault, and offshore wind farm integration. Simulation results validate superiorities and effectiveness of PoFoPID control in comparison of that of PID control and feedback linearization sliding-mode control (FLSMC), respectively.