Research On Key Technology For The Control System Of Actively Resonant Wave Energy Generator

Under the background of energy crisis in the world,development and utilization of ocean energy become a focus.Although all kinds of wave energy utilization device emerge in endlessly,most of them have the shortcoming of low conversion efficiency.Based on the platform of controllable resonance wave energy generation technology,the application of active resonance and the maximum power point tracking control strategy,to a certain extent,improve the conversion efficiency of wave energy power generation device respectively from two aspects: the frequency and height of wave.The main work is as follows:Firstly,the background and significance and the research status of the wave energy utilization technology is introduced in this paper.Then the research content of this paper is brought out.Secondly,the basic theory of wave energy,the physical structure and the working principle of actively resonant wave energy generation system is introduced,and the point that the acquisition of characteristic parameters of ocean wave in real time is the key to improve the efficiency of power extraction.Thirdly,according to the requirement of the power system for real-time monitoring of the wave characteristic parameters,a set of low-cost wave buoy system was designed based on the STM32 microcontroller and MEMS sensors.According to the features of the wave,the complementary filter,quaternion,short-time Fourier algorithm was used to calculate the wave characteristic parameters such as frequency,wave height and direction,and the feasibility of the buoy scheme has been verified through experiment.Finally,according to the characteristics of the generation device,the control strategy of active resonance and maximum power point tracing have been used,and a set of hardware scheme based on STM32F4 microcontroller have been designed.Based on the idea of capturing maximum energy by resonance,and the feature of rigidity adjuster modifying the natural frequency of the pendulum,a closed-loop control system was designed to implement active resonance of generation system by using of PID controller.Inspired by photovoltaic and wind power generation system,the control strategy of maximum power point tracking based on the algorithm of gradient descent was adopted to make the generation system working in the maximum power when the condition of the wave height changing.Two kinds of control strategies improved the conversion efficiency of wave energy generation device to a certain extent.