Advanced Control of Offshore Semi-submersible Wind Turbines

风能是世界上增长最快的可再生和可持续发电能源。提高风力涡轮机和风力发电场效率的一个趋势是将它们转移到深水海域，那里的风比陆上风更强、更稳定，我们需要在那里让涡轮机漂浮起来。由于基础不固定，浮式风力机可以利用其重新定位的能力来缓解风力机之间的尾迹效应，增加多个风力机的总功率，并降低风电场中风力机的疲劳负荷。然而，浮式海上风力发电机组运行中的挑战之一是以不可预测的方式作用于平台的海浪干扰。为了提高风力发电能力，需要通过控制工程技术抑制平台和涡轮机在波浪激励下的不良振动运动，从而最小化风能成本。本项目的主要目标是建立半潜式平台上实用规模的浮式海上风力机的控制技术，以最大限度地提高风能捕获能力，最大限度地减少结构载荷，从而降低风能成本。实现这一目标的方法在四个方面具有原创性和新颖性。首先，对于控制器的设计，我们采用了面向控制的模型，该模型可以显式地考虑平台三维运动的动力波动效应。其次，我们利用最近发展起来的线性变参数控制技术来设计前馈和反馈控制系统。第三，为了进一步抑制波浪引起的平台振动，我们采用了实时波压测量进行前馈和预测控制。最后，作为高层实时风电场布局优化下的底层控制，我们只利用气动力对平台进行位置控制，不增加任何额外的执行器。*为了实现上述主要目标，本方案的技术任务包括：1)扩展面向控制的建模技术，使其具有结构灵活性和将气动分配到三个叶片；2)基于模型设计半潜式风力机的线性变参数控制器；3)设计半潜式平台可移动范围内的平台位置控制器。4)本程序设计的面向控制的建模和控制器设计软件开发。将进行仿真研究以验证所开发的模型和控制器。*研究成果将对加拿大和世界范围内的环境、社会和经济产生重大影响。它将在短期和长期内增加风能行业的就业、投资和社区利润。它将提供一个干净的环境，不会对周围环境造成视觉和噪音影响。

Wind is the fastest growing renewable and sustainable energy in electricity generation around the world. One trend to improve the efficiency of wind turbines and wind farms is to move them into the deepwater sea where the wind is stronger and more consistent than the onshore wind and where we need to set the turbines afloat. Due to the unfixed foundation, floating wind turbines can take advantage of their relocation capability to alleviate the wake effect between turbines, to increase the total power of multiple turbines, and to reduce the fatigue load of the turbines in the wind farm. However, one of the challenges in the operation of floating offshore wind turbines is the wave disturbance which acts on the platforms in an unpredictable manner. To enhance wind power generation, the undesirable vibration motions of the platform and the turbine excited by the wave need to be suppressed, and consequently wind energy cost need to be minimized, by control engineering technologies.******The main goal of this program is to establish control techniques for a utility-scale floating offshore wind turbine on a semi-submersible platform, in order to maximize the wind power capture and minimize the structural loading, thereby reducing the wind energy cost. The approach to this goal is original and novel in four ways. Firstly, for controller design, we adopt control-oriented models that can involve explicitly dynamical wave effect to the platform's 3-D motion. Secondly, we exploit our recently-developed linear parameter-varying control techniques to design feedforward and feedback control systems. Thirdly, to further suppress the wave-induced platform vibration, we employ real-time wave pressure measurement for feedforward and predictive control. Lastly, as a low-level control under the high-level real-time wind farm layout optimization, we account for position control of the platform by making use of only the aerodynamic force, without adding any extra actuator.******To achieve the main goal described above, technical tasks in this program include 1) extension of the control-oriented modelling technique with structural flexibilities and the aerodynamic force distributed to three blades, 2) model-based design of linear parameter-varying controllers of a semi-submersible wind turbine, 3) design of platform position controllers within the movable range of the semi-submersible platform, and 4) software development for control-oriented modelling and controller design devised in this program. Simulation studies will be conducted to validate the developed models and controllers.******The research outcome will have a great impact on the environment, society and economy in Canada and worldwide. It will increase employment in the wind energy sector, investments and profits to the community, in both the short and long term. It will provide a clean environment without visual and noise impact on the surrounding environment.