Active control for multi-degree-of-freedom wave energy converters with load limiting
Active control for multi-degree-of-freedom wave energy converters with load limiting
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DOI：
10.1016/j.renene.2020.05.073
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发表时间：
2020-10
期刊：
影响因子：
8.7
通讯作者：
A. Hillis;C. Whitlam;A. Brask;J. Chapman;A. Plummer
中科院分区：
文献类型：
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作者：
A. Hillis;C. Whitlam;A. Brask;J. Chapman;A. Plummer
主动控制策略是实现波浪能转换器（WEC）高效、安全和经济运行的关键。已经开发了许多策略，但大多数研究仅限于WEC的简化仿真模型，这些模型不能代表真实的设备。此外，许多研究假设完美的知识的波浪激振力，这是一个必要的输入，许多控制策略。在这项工作中，目的是开发一种主动控制策略，以最大限度地提高功率捕获，同时限制设备负载，以延长其使用寿命。设计了一种带有线性二次型调节器速度跟踪环的近似最优速度跟踪（AVT）控制器。该控制器被应用于一系列现实海况下WaveSub多自由度WEC的经过验证的全尺寸非线性模型。控制器中只使用物理上可测量的量，这意味着所开发的策略可部署在真实的系统中。主动控制系统的性能相比，一个最佳调谐的被动阻尼系统，并观察到高达80%的功率增益。这种方法在以最小的附加设备成本提供功率捕获的显著增加方面显示出重要性，因此可能导致能量成本的重大改善。
An active control strategy is a key component to enable efficient, safe and economical operation of a wave energy converter (WEC). Many strategies have been developed, but most studies are limited to simplified simulation models of WECs which are not representative of real devices. Furthermore, many studies assume perfect knowledge of the wave excitation force, which is a necessary input to many control strategies. In this work, the aim is to develop an active control strategy to maximise power capture while limiting device loading to prolong its lifetime. An approximate optimal velocity tracking (AVT) controller with a Linear Quadratic Regulator velocity tracking loop is designed. The controller is applied to a validated full-scale nonlinear model of the WaveSub multi-DOF WEC in a range of realistic sea states. Only physically measurable quantities are used in the controller, meaning the strategy developed is deployable in a real system. The performance of the actively controlled system is compared to an optimally tuned passively damped system, and power gains of up to 80% are observed. This approach shows significance in providing a substantial increase in power capture for minimal additional device cost and therefore a major improvement in cost of energy would likely result.