双浮体直驱波浪发电装置建模分析与基于模型预测控制的能量提取算法研究  

Modelling and Analysis of the Two-Body Direct-Drive Wave Energy Converter and Optimal Energy Extraction Method Based on Model Predictive Control

作　　者：黄宣睿 林泽川 肖曦[1] Huang Xuanrui;Lin Zechuan;Xiao Xi(Department of Electrical Engineering,Tsinghua University,Beijing 100084)

机构地区：[1]清华大学电机系,北京100084

出　　处：《电工技术学报》2024年第2期445-454,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金资助项目(U1806224)。

摘　　要：基于振荡浮体结构的直驱波浪发电装置具有损耗低、控制灵活等优点,近年来,逐渐成为波浪发电领域的研究热点。双浮体直驱波浪发电装置不需要海上固定平台,能够通过锚系结构在海水中工作,是一种工程可行的直驱波浪发电方案,但其动力学模型更为复杂,相关控制算法缺少实际装置测试。该文通过等效电路的方法对双浮体装置进行建模分析,指出采用张力锚结构可将双浮体装置等效为单浮体装置进行分析,简化控制器的分析与设计,从而建立基于模型预测控制的高效波浪能提取问题。提出一种结合波浪激励力辨识、预测与快速模型预测求解的控制算法,并且设计了双浮体直驱波浪发电装置,在不同波浪条件下进行了相关实验测试。实验结果表明,所提控制算法能够在有效降低运算复杂度的前提下提高装置的波浪能提取效率。With low loss and flexible control,a direct-drive wave energy converter(WEC)based on oscillating body structure has become a research hotspot in wave energy.Through the mooring system,two-body direct-drive WEC,independent of off-shore fixed platforms,is a promising solution to wave energy utilization.However,the two-body WEC utilizes relative motion between upper and lower float to generate electricity,which makes modelling and optimal energy extraction control more difficult.A two-body WEC can be regarded as two power sources with different voltages and resistance paralleled to output electricity through the equivalent method.Furthermore,this two-paralleled power source can be equivalent to a single source model,similar to a single-body WEC.Therefore,modelling and energy extraction characteristics of two-body WEC are simplified.The stiffness of mooring has a great effect on maximum wave energy extraction.The results show that the mooring should be as stiff as possible to avoid energy extraction loss.In this case,the two-body WEC can be equivalent to a single-body WEC:the upper float harnesses wave energy,and the lower float along with the mooring system acts as a fixed base.Moreover,the design of a two-body WEC with a pretension mooring system is put forward.Model predictive control(MPC)is a state-of-the-art method for optimal energy extraction in wave energy.Based on the equivalent model,the MPC problem for maximizing wave energy extraction considering generator force and float displacement constraints is formulated.For wave excitation force prediction,the Kalman filter is used to achieve excitation force identification,and the autoregressive model is used for excitation force prediction.Considering the computation complexity of the MPC solution,a fast solution algorithm is put forward,and the previous step is set as the initial iteration of the current step.Thus,only one iteration is required.Compared with the conventional MPC that requires 3~5 interactions,the proposed fast solution algorithm can save up to 8

关 键 词：双浮体直驱波浪发电 能量提取优化算法 装置建模分析 波浪水槽 模型预测控制 

分 类 号：TM619[电气工程—电力系统及自动化]