Control of a Twin-Turbine Submerged Floating System (TTSFS) with Model Predictive Control (MPC) is discussed in this paper. The TTSFS has been developed to harvest Ocean Current Energy, and it has twin turbines and a weather-vaning ability by using a single-point mooring system. The TTSFS is perturbed and the output power fluctuates, due to turbulence in the flow. The aim of this study is to show the possibility to mitigate motions of the TTSFS and fluctuations of the output power simultaneously in turbulent flow, using blade pitch control and torque control of the generator. The control simulation is performed using a motion simulator which can simulate nonlinear 6 DoF motions of the TTSFS coupled with rotating twin-turbines and a single-point mooring system. Based on the simulation results, it is concluded that motion control is necessary to prevent large asymmetric motion which may affect the integrity of the mooring system. Also, MPC has the ability to mitigate motions of the TTSFS and the fluctuation of the output power simultaneously. However, there are tradeoffs among the variance of the motions, the variance of the angular velocity or the torque and the average of the output power.

本文讨论了采用模型预测控制（MPC）的双涡轮潜水浮系统（TTSFS）的控制。TTSFS被开发来收集洋流能量，它具有双涡轮机和通过使用单点系泊系统的风向标能力。由于流动中的湍流，TTSFS受到干扰，输出功率也发生波动。这项研究的目的是显示利用叶片桨距控制和发电机转矩控制同时减轻湍流中TTSFS的运动和输出功率波动的可能性。使用运动模拟器执行控制仿真，该运动模拟器可以模拟TTSFS的非线性6 DoF运动以及旋转双涡轮机和单点系泊系统。根据仿真结果，结论是运动控制对于防止可能影响系泊系统完整性的大的不对称运动是必要的。而且，MPC能够同时缓解TTSFS的运动和输出功率的波动。然而，在运动的方差，角速度或转矩的方差和输出功率的平均值之间存在折衷。