<![CDATA[The increasing penetration of wind energy systems requires advanced control strategies capable of maintaining stable operation during grid disturbances while complying with modern GC requirements. This paper proposes a COA-based control scheme for a DC chopper integrated into a PMSWG system to enhance its FRTC under severe voltage disturbances. The COA is employed to optimally tune the controller parameters, ensuring effective regulation of the DC-link voltage and improved transient performance. The proposed approach is evaluated under four critical grid conditions, including three voltage dip scenarios corresponding to 100%, 80%, and 40% retained voltage levels, as well as a 20% voltage swell condition. Simulation results demonstrate that the proposed controller maintains the DC-link voltage close to its reference value of 1150 V, preventing excessive overvoltage during fault events and reducing stress on power electronic converters. Moreover, the control strategy satisfies GC requirements by providing appropriate reactive power support during VDs while ensuring controlled active power transfer. The optimized controller effectively suppresses electromagnetic torque oscillations, limits transient current peaks in the GSC, and enables rapid recovery of generator speed following fault clearance. Comprehensive MATLAB/Simulink studies confirm that the proposed COA-based DC chopper control significantly improves system transient stability, enhances grid-support capability, and ensures reliable operation under both voltage dip and swell conditions. In addition, the improved DC-link voltage regulation contributes to increased converter lifetime and reduced operational downtime, demonstrating the practicality and effectiveness of the proposed solution for modern wind energy conversion systems.]]>
