Hydrodynamic Performance And Optimal Control Of Oscillating Float Wave Energy Device

As the global demand for energy growing,it has promoted the development of new energy technologies,especially wave energy technologies.A wide variety of wave energy devices are widely used.The oscillating float wave energy device has a simple structure,a wide application range,and great development potential.Some oscillating float wave energy devices in foreign countries are close to commercialization,while domestic development is relatively lagging behind.Most of China's sea areas are semi-enclosed,with short wave periods and relatively low energy density,which are quite different from foreign sea conditions.Therefore,we must take the road of independent research and development.In this paper,the research on the oscillating float wave energy device is studied.The main contents of the research are as follows:(1)Based on the linear wave theory of potential flow,a hydrodynamic mathematical model of the wave energy device is established.The basic hydrodynamic coefficients of wave energy devices are calculated by commercial hydrodynamic software AQWA.On this basis,the effects of float diameter draft ratio,PTO damping coefficient and anchor chain on the hydrodynamic performance of wave energy devices are studied through the established mathematical model.The impact of hydrodynamic performance.The wave energy device optimization and improvement scheme applicable to China's sea area is proposed.(2)When the wave energy device works,there will actually be six degrees of freedom motion,in which the pitch motion is more obvious than other degrees of freedom motion,and it is often studied that the oscillatory float wave energy device generally only considers the wave motion device heave motion.In this paper,considering the influence of pitch on the wave energy device,the wave energy device simulation model is built on the MATLAB/SIMULINK platform to analyze the influence of the pitch on the motion performance and power characteristics of the wave energy device under different sea conditions.(3)Deriving the state space expression of the wave energy device,establishing the objective function according to the expression,and considering the constraints of the float velocity,displacement,PTO output force,etc.,discuss the application of the linear model predictive control on the wave energy device.Combined with hydrodynamic optimization,the optimal control of the wave energy device in the wave is optimal and the operating state is optimal.