Research On Optimization And Control Strategy Of The Buoy Driven By Ocean Thermal Energy

Ocean detection buoy is an underwater detection instrument that achieve profiling movement in seawater by changing its own buoyancy.It is an important part of the global observation network and is of great significance to the development of marine resources,monitoring of extreme weather,and protection of ocean security.Most of the existing buoys are powered by batteries,and the service life of the buoys is severely limited.In this paper,a detection buoy driven by ocean thermal energy is developed and researched,and the structural layout and functional unit design of the buoy are described in detail.In order to realize the selfsupply of energy in the working process of the buoy,a multi-objective optimization design is carried out on the shape and structure of the buoy.The control strategy of the power generation system is deeply studied and verified by experiments.The main work content is as follows:Looking at the current research status of ocean temperature difference energy and ocean detection buoys at home and abroad,the temperature difference energy in detection instruments driven by temperature difference energy is mostly used for buoyancy adjustment of buoys,and control and communication systems still rely on battery power.This paper aims to design and study a set of A buoy system that can generate self-supplied electricity from temperature difference can be realized.According to the working principle and working process of the buoy,the hydraulic system design of each functional unit of the buoy is carried out,and the overall structure and unit layout of the buoy are analyzed and modeled in detail.The heat exchange system of the buoy adopts a tubular structure with a built-in skin bag,and choose n-hexadecane as the heat-exchanging medium,and the pressure-resistant shell of the buoy is made of carbon fiber material and introduced reinforcing ribs to meet the needs of underwater work.The buoy can change the buoyancy by adjusting its own drainage volume to realize the profile motion.In order to improve the motion performance of the buoy and reduce energy consumption,this paper conducts multi-objective optimization on the shape and structure of the buoy.The overall shape of the buoy is designed with a drop-shaped rotator,and the busbar of the gyratory body is expressed by an equation with adjustable parameters.Based on CFD,the motion performance of the buoy is analyzed,and the neural network is trained using the performance data of the buoy under different parameters to obtain the shape parameters of the buoy.The mapping relationship between the buoy and the motion performance,the genetic algorithm is introduced to perform multi-objective optimization on the buoy,draw the Pareto front,find the optimal solution,and complete the optimization of the buoy’s streamlined shell with low energy consumption and high performance.In order to improve the power generation efficiency of the buoy and increase the power generation capacity,the temperature difference energy power generation system of the buoy was studied,and a set of power generation system control strategy was designed.In this paper,the buoy power generation system is mathematically modeled,the energy loss in the power generation process is analyzed by establishing an efficiency model,the control parameters and control objectives are determined,the neural network is trained using experimental data,and the key components are identified for the system,and Simulink is used to establish The simulation model of the power generation system was established,the accuracy of the efficiency model was tested,and the control strategy of the maximum efficiency point tracking was designed based on the gray wolf algorithm,and the tracking control of the buoy power generation system was carried out,and the feasibility of the algorithm was verified in the simulation software.Finally,on the basis of the above research and design,the key structure of the buoy was processed and tested,the internal parts of the buoy were designed and selected,and the development of the buoy prototype was preliminarily completed.At the same time,a test platform for the power generation system was designed and built,and the power generation performance and maximum efficiency tracking control of the buoy were actually tested.The effectiveness and reliability of the control strategy were verified by comparison of experimental data.