Floating vertical axis wind turbines (VAWTs) have many advantages over floating horizontal axis wind turbines (HAWTs) at large scales in deep water; however, there are several key challenges to overcome as well. One of the challenges is accurate prediction of the dynamic motion and loads performance of a floating VAWT. A new semi-coupled aero-servo-hydro method is developed to assess dynamic responses of a floating VAWT by modeling the system as a 7-degree-of-freedom (7-DOF) model: the supporting platform is considered as a 6-DOF rigid body; the rotation of the rotor is considered as the 7th DOF. Aerodynamic, hydrodynamic, and mooring loads and control of the rotor speed are fully considered. This model can predict performance of floating VAWTs with reasonable fidelity according to validation with OrcaFlex through static and dynamic responses of a floating VAWT with Darrieus rotor operating on a new tension-leg platform (TLP). Being a reduced complexity model, the 7-DOF model can be efficiently applied to assess performance of the newly designed floating VAWT. This model is used to examine the relative contributions of aerodynamic and wave loads imparted to the floating system and the benefits of a three-bladed VAWT over a two-bladed VAWT through dynamic and fatigue analysis.

浮式垂直轴风力涡轮机（VAWTs）在深水大尺度上比浮动式水平轴风力机（HAWTs）有很多优势；然而，也有几个关键挑战需要克服。挑战之一是准确预测浮动 VAWT 的动态运动和负载性能。通过将系统建模为 7 自由度 (7-DOF) 模型，开发了一种新的半耦合气动伺服液压方法来评估浮动 VAWT 的动态响应：支撑平台被视为 6-自由度刚体；转子的旋转被认为是第 7 个自由度。充分考虑了空气动力、水动力和系泊载荷以及转子速度的控制。该模型可以根据 OrcaFlex 的验证，通过在新张力腿平台 (TLP) 上运行的带有 Darrieus 转子的浮动 VAWT 的静态和动态响应，以合理的保真度预测浮动 VAWT 的性能。作为一种降低复杂性的模型，7-DOF 模型可以有效地应用于评估新设计的浮动 VAWT 的性能。该模型用于通过动态和疲劳分析检查传递给浮动系统的空气动力和波浪载荷的相对贡献，以及三叶片 VAWT 相对于两叶片 VAWT 的优势。