双模式水下航行器波浪能发电的模型预测控制

Model Predictive Control of Wave Power Generation for Dual-mode Underwater Vehicles

双模式水下航行器在捕能发电模式下的工作原理与振荡双浮子式波能装置相同,为了提高航行器的波浪能发电功率,必须采取有效的控制策略。模型预测控制能有效提高传统波能装置的输出功率,但通常将PTO系统等效简化为对波能装置的作用力,并以PTO力作为控制量,优化系统的机械功率输出。针对双模式水下航行器的结构和功能特点,提出以航行器本体推进器为执行机构的模型预测控制方法,对双浮子的运动状态进行调节,进而实现装置发电功率最大化。为验证控制方法的有效性,建立了双浮子从波浪捕能到电能输出的状态空间模型,在Simulink中搭建了模型预测控制器仿真模型,分别求解了随机波浪激励下有无模型预测控制的装置电功率输出,并对比了模型预测控制提高的能量输出和执行机构的能量消耗。结果表明,提出的模型预测控制方法有效提升了装置的电能输出,平均发电功率增幅可达38.4%。

The working principle of dual-mode underwater vehicles in power generation mode is the same as oscillating double-float wave energy converters(WECs).In order to increase the output power,effective control strategies must be adopted.The model predictive control(MPC)can effectively improve the output power of traditional WECs,but the power take-off(PTO)system is usually simplified as a counter acting force,which is used as the control quantity to optimize the mechanical power output of the system.Based on the structural and functional characteristics of dual-mode underwater vehicles,the propeller is proposed as the actuator of MPC in this paper.In order to verify the effectiveness of the control method,a state-space model of the double-float WEC from wave energy capture to electrical energy output is established,and a MPC controller is established in Simulink.The electric power output of the device with and without MPC under random wave excitation are solved.And the energy output improved by MPC is compared with the energy consumption of the actuator.The results show that the proposed MPC method can effectively improve the electrical power generation.