Passive pitch blade systems research and lab testing for reducing loads on tidal turbines

在目前的最先进水平下，潮汐涡轮机产生的能源的水平成本太高，这种技术在商业上是不可行的，尽管潮流提供了一种可预测和可持续的能源来源。对于具有可变叶片螺距的涡轮机，主动控制系统和机械执行器已被发现是故障的主要来源，因此增加了运行成本。然而，恒桨距涡轮机承受高于额定转速的高扭矩和推力负荷，因此具有较低的截止转速，从而导致较低的能量产量。被动叶片螺距控制可以通过提高切割速度来降低LCOE，从而降低产量，而不会导致重大的可靠性问题。研究表明，弯扭耦合有可能为潮汐涡轮机提供有限程度的被动叶片俯仰。已经出版了关于开发风力涡轮机被动变桨机构的文献，并进行了建模，以证明为潮汐涡轮机实施被动叶片变桨的好处。该项目的创新之处在于寻求开发和实施一种用于商业潮汐涡轮机的被动俯仰系统。

At the current state-of-the-art, the levelised cost of energy generated by tidal turbines is too high for such technologies to be commercially viable, despite the fact that tidal currents offer a predictable and sustainable source of energy. For turbines that have variable blade pitch, the active control system and mechanical actuators have been found to be major sources of failure and therefore increase operating costs. Constant blade pitch turbines, however, experience high torque and thrust loads above rated speed, and therefore have low cut-out speeds, resulting in lower energy yields. Passive blade pitch control offers the potential to reduce the LCOE by increasing the cut-out speed, and therefore yield, without causing major reliability issues. Research has shown that bend-twist coupling has the potential to provide a limited degree of passive blade pitching for tidal turbines. Literature has been published regarding the development of passive pitch mechanisms for wind turbines, and modelling has been undertaken to demonstrate the benefits of implementing passive blade pitching for tidal turbines. The novelty of this project lies in seeking to develop and implement a passive pitching system for a commercial tidal turbine.