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This work analyzes the stability and performance of an offshore solar-concentrated ocean thermal energy conversion system (SC-OTEC) tied to an onshore AC grid. The OTEC is a system where electricity is generated using small temperature differences between the warm surface and deep cold ocean water. Existing control methods for SC-OTEC systems lack coordination, hindering dynamic stability and effective damping for the synchronous generator (SG). These methods struggle to quickly adapt to sudden disturbances and lack the capability to adequately reject or compensate for such disturbances due to complex control constraints and computational demands. To this regard, a control strategy combining sliding mode control (SMC) and a power system stabilizer (PSS) to improve the SC-OTEC dynamic stability and damping features for the SG. Moreover, an auxiliary secondary automatic voltage regulator is assembled with a non-linear exciter system to provide damping features. The proposed PID-PSS and secondary AVR controller gains are adaptively tuned using a modified whale optimization algorithm with the balloon effect modulation. The studied SC-OTEC is tested through MATLAB/Simulink under a severe 3ϕ short-circuit fault, solar radiation variations, and a change in surface seawater temperature as well as changes in local loads. The final findings approved that the proposed control strategy preserves a strong performance and can mimic effectively the proposed SC-OTEC damping compared to the conventional system.本研究针对与陆上交流电网相连的海上聚光型海洋温差能转换系统（SC-OTEC）的稳定性与运行性能展开分析。海洋温差能转换系统（OTEC）是利用表层暖海水与深层冷海水之间的微小温差进行发电的系统。现有SC-OTEC系统的控制方法缺乏协调机制，这会阻碍同步发电机（SG）的动态稳定性与有效阻尼性能。由于控制约束复杂且计算量较大，此类控制方法难以快速响应突发扰动，也无法充分抑制或补偿此类扰动带来的影响。针对上述问题，本文提出一种将滑模控制（SMC）与电力系统稳定器（PSS）相结合的控制策略，以提升SC-OTEC的动态稳定性，并改善同步发电机（SG）的阻尼特性。此外，本文还将辅助式二级自动电压调节器（AVR）与非线性励磁系统集成，以提供阻尼特性。本文采用带有气球效应调制的改进型鲸鱼优化算法，对所提出的PID-PSS控制器与二级自动电压调节器的参数进行自适应整定。本文通过MATLAB/Simulink平台，在严重三相短路故障、太阳辐射变化、表层海水温度变化以及本地负荷波动工况下，对所研究的SC-OTEC系统进行了测试。最终研究结果证实，相较于传统控制系统，本文所提出的控制策略具备优异的运行性能，可有效实现SC-OTEC系统的阻尼特性优化。