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，那里的风比陆上风更强，更稳定，我们需要将涡轮机漂浮起来。浮动式风力发电机由于基础不固定，可以利用其搬迁能力，减轻机组间的尾流效应，提高多台机组的总功率，降低风电场机组的疲劳载荷。然而，浮式海上风力涡轮机的操作中的挑战之一是以不可预测的方式作用在平台上的波浪扰动。为了增强风力发电，需要通过控制工程技术来抑制由波浪激发的平台和涡轮机的不期望的振动运动，并且因此需要最小化风能成本。该项目的主要目标是建立半潜式平台上的公用事业规模漂浮式海上风力涡轮机的控制技术，以最大限度地提高风能捕获率并最小化结构载荷，从而降低风能成本。实现这一目标的方法在四个方面是新颖的。首先，对于控制器的设计，我们采用了面向控制的模型，可以显式地考虑动力学波动对平台三维运动的影响。其次，我们利用我们最近发展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，我们采用实时波压力测量的前馈和预测控制。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，本计划的技术任务包括：1）扩展面向控制的建模技术，使其具有结构柔性和分布到三个叶片的气动力，2）基于模型设计半潜式风力涡轮机的线性参数变化控制器，3）设计半潜式平台可移动范围内的平台位置控制器，（4）面向控制的建模和控制器设计的软件开发。将进行模拟研究，以验证开发的模型和控制器。**研究成果将对加拿大乃至全球的环境、社会和经济产生重大影响。它将在短期和长期内增加风能部门的就业机会、投资和社区利润。这将提供一个清洁的环境，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.