Study On Pressure Balance Of Multi - Buoyo Pendulum Based On Digital Hydraulic Cylinder Block

With the development of economy, the demand for energy has an great increasing in the modern society. But the formation period of traditional fossil energy is too long. It is also much pollutional to the environment. So the research of the renewable, green, environmentally friendly new energy has become an important subject. Wave energy is a kind of oceanic energy. It is abundant, clean and renewable. It is a good choice to replace fossil energy. As the secondary energy conversion mechanism of most of the wave energy generation devices, the hydraulic cylinder has an important role in the whole system. In this paper, a new type structure-the digital control hydraulic cylinder group is used to replace the conventional hydraulic cylinder in the buoyancy pendulum wave energy generation device. Its running state is controlled on two parallel generation system to achieve the goal that the pressure is balanced and the sporadic wave energy is gathered to generate electricity together. The content of each chapter is as follows:First chapter, this chapter illustrates the significance of wave energy development and the research state of wave energy generation technology. The principle of wave energy generation device is analyzed from the application of the hydraulic system in the wave energy development. It is stated that the use of the hydraulic cylinder as the key component in hydraulic system and the secondary energy conversion mechanism of the wave energy generation device. This chapter introduces the technology and development of the array type wave energy generation equipment, the research state of gathering energy separately and generating together. Finally, the significance and content of this research is introduced.Second chapter, this chapter introduces the working principle of the digital control hydraulic cylinder group, design the basic parameters and the mechanical structure. The main parts of the digital hydraulic cylinder group is illustrated. So are the high speed valve and displacement sensor. Finally, this chapter conducts a simple simulation of the digital hydraulic cylinder group.Third chapter, this chapter introduces the principle of the whole buoyancy pendulum wave energy generation device and the running of the digital hydraulic cylinder group, conducts a simulation of high speed valves in the digital hydraulic cylinder group which its stress are dynamic characteristic and static characteristic. Keeping the running state of the digital hydraulic cylinder group this chapter simulates the running of buoyancy pendulum wave energy generation system, illustrates the function of changing the area. The pressure balance control strategy is used in two parallel generation system. Finally, this chapter conducts a simulation of this generation system which has added the control strategy and verifies the feasibility of this strategy.Fourth chapter, based on the theoretical analysis and modeling simulation, the experiment platform is built. The structure of this scheme is designed. The digital hydraulic cylinder group is controlled by the microcontroller programming successfully. The experiment result is analyzed and compared at last.Fifth chapter, summary, putting forward to the work direction in the future.