Enhancing primary frequency support from DFIG with SSSC optimized through Honey Badger algorithm

Technical advancements in the renewable sector lead to an increased penetration, primarily of wind generation, into the grid. Conventional generators, the main contributors to system inertia, are being replaced by wind generation to facilitate sustainable power production. Owing to minimal inertial support with converter-based generators, overall system inertia is reduced, which in turn causes severe issues in the power system network, mainly related to frequency stability. Emulating inertial response from wind turbines is a possible solution. Wind energy systems can be equipped with supplementary controllers to enhance system inertia by extracting energy stored in turbine rotors, blades, and other rotating parts. The advanced wind turbines, provided with inertial control, perform better than the conventional wind-penetrated system. However, adverse effects such as secondary frequency dip may be observed after the inertial response period. Static Synchronous Series Compensator (SSSC), a class of FACTS devices, is employed to improve the power transfer capability of tie lines, that connect remotely located wind farms to the grid. In addition to improving power quality, SSSC aids in the frequency stability of the grid by damping out low-frequency oscillations in lines and enhancing inter-area power exchange. In this paper, inertial support from wind turbine generators (WTG) is presented as a solution to enhance the primary frequency response capability of the wind-penetrated system. The system response is further enhanced with the integration of SSSC. The variation of net inertia and droop in the system with penetration is accommodated for analysis. The controller parameters are optimized with the latest Honey Badger Algorithm (HBA), which performs better than other meta-heuristic optimization methods. The efficiency of the HBA is also compared with other prominent algorithms.