Research On Distributed Wave Energy Control Based On Integrated Digital Controlled Hydraulic Cylinder Group

Among the variety of energies in the ocean,wave energy is abundantly and highly available.In order to improve the conversion efficiency of wave energy and reduce the cost of single unit,distributed wave energy generation system has become the research hotspot nowadays.This paper mainly studies the conversion from wave energy to hydraulic energy based on pendulum wave energy generation device.In this project,an integrated digital control hydraulic cylinder group(IDCHCG)replaces the traditional hydraulic cylinder,so that we can control the output of the resistance torque to adjust buoy pendulum motion state to improve the capture efficiency.On this basis,a hydraulic system of distributed wave energy capture system is constructed in this paper.The maximum power capture of distributed wave power generation system is achieved through pressure control and power regulation of hydraulic system.The main contents of this thesis are as follows:In chapter one,the current research progress of wave power plant,IDCHCG and distributed wave power generation hydraulic system at home and abroad are summarized,and the research significance and research content of the project are illustrated.In chapter two,the kinematic characteristics of buoyancy pendulum in waves were analyzed based on the theory of micro-amplitude wave.The control principle,output pressure and output flow characteristics of the IDCHCG were analyzed.The hydraulic system of distributed wave energy generation system is designed,and the control strategy of hydraulic system is researched.The fuzzy control strategy of pressure is proposed.In chapter three,the model of the IDCHCG is established,and the power curve of the wave power generation system based on the output resistance of the IDCHCG is analyzed.The maximum power capture algorithm based on bisection variable step search algorithm is proposed.In chapter four,the hydraulic system of distributed wave energy generation is established by AMESim and the control system is established by Lab VIEW.AMESim dynamic link library achieves a joint simulation of the two to verify the feasibility of control algorithms.In chapter five,hardware and software design of the controller are completed and a semi-physical test platform is set up.The start-up pressure and power characteristics of the IDCHCG were tested and the semi-physical test of distributed wave power generation was carried out.In chapter six,the research work has been summarized.As an extension,this thesis also made some prospects towards the subsequent research work.