Structural loads of wind turbines are becoming critical because of the growing size of wind turbines in combination with the required dynamic output demands. Wind turbine tower and blades are therefore affected by structural loads. To mitigate the loads while maintaining other desired conditions such as the optimization of power generated or the regulation of rotor speed, advanced control schemes have been developed during the last decade. However, conflict and trade‐off between structural load reduction capacity of the controllers and other goals arise; when trying to reduce the structural loads, the power production or regulation performance may be also reduced. Suitable measures are needed when designing controllers to evaluate the control performance with respect to the conflicting control goals. Existing measures for structural loads only consider the loads without referring to the relationship between loads and other control performance aspects. In this contribution, the conflicts are clearly defined and expressed to evaluate the effectiveness of control methods by introducing novel measures. New measures considering structural loads, power production, and regulation to prove the control performance and to formulate criteria for controller design are proposed. The proposed measures allow graphical illustration and numerical criteria describing conflicting control goals and the relationship between goals. Two control approaches for wind turbines, PI and observer‐based state feedback, are defined and used to illustrate and to compare the newly introduced measures. The results are obtained by simulation using Fatigue, Aerodynamics, Structures, and Turbulence (FAST) tool, developed by the National Renewable Energy Laboratory (NREL), USA.

中文翻译：

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风力涡轮机的结构负荷减轻控制：一项新的性能指标

由于风力涡轮机的尺寸不断增加以及所需的动态输出需求，风力涡轮机的结构载荷变得至关重要。因此，风力涡轮机塔架和叶片受结构载荷的影响。为了减轻负荷，同时保持其他所需条件，例如优化发电功率或调节转子速度，在过去的十年中开发了先进的控制方案。但是，控制器的结构减轻负荷能力与其他目标之间存在冲突和折衷。当试图减少结构负荷时，功率或调节性能也会降低。当设计控制器以评估与冲突控制目标有关的控制性能时，需要采取适当的措施。现有的结构载荷测量方法仅考虑载荷，而没有涉及载荷与其他控制性能方面之间的关系。在此贡献中，冲突被明确定义并表达出来，以通过引入新颖的措施来评估控制方法的有效性。提出了考虑结构载荷，功率产生和调节的新措施，以证明控制性能并制定控制器设计标准。所提出的措施允许图形化描述和数字标准来描述冲突的控制目标以及目标之间的关系。定义了两种用于风力涡轮机的控制方法，即PI和基于观察者的状态反馈，以说明和比较新引入的措施。结果是通过使用疲劳，空气动力学，