Design And Development Of Underwater Monitoring Device For Tidal Stream Turbine

With the development of society and technology, people become more and more dependent on energy, and energy has become crucial for human’s survival and development. However, with a large number of exploit, traditional fossil energy is confronted with depletion; at the same time, due to the burning and exploit of fossil fuels, environmental pollution problems are growing worse. The recent haze weather once again sounded the alarm for us. For global sustainable development, development and exploit of green renewable energy has become the consensus of the world. Tidal energy as a kind of ocean energy, abundant in reserves and regular in time, is a green renewable energy without pollution, so it has drawn more and more attention all over the world.The subject comes from the special fund for marine renewable energy of the State Oceanic Administration - "500kW marine energy independent power system demonstration project". In this project, Ocean University of China is responsible for 100kW tidal stream generation, and has designed two 50kW tidal stream generation turbines. After the turbines are mounted at the bottom of the sea, in order to ensure the safety of the turbines and extract maximum energy, it is necessary to monitor the operation environment and operation state of the turbines, as well as control the pitch angle.An underwater monitoring device is designed in this paper for tidal current generation sets according to above requirements. This device consists of two parts: the underwater monitoring system and the pitch control system, witch achieved parameters monitoring and pitch angle control. The main work of this paper is as follows:1. Hardware and software are designed for the underwater monitoring system. Underlying device drive and information acquisition are realized for multi sensors, which achieves the monitoring of the internal and external environment parameters as well as the running status of the turbine;2. The design and development of the pitch control system are carried out. Three closed-loop control algorithm, which is current, speed and angle, is proposed. One-click-pitch function is designed to realize precision control of the blade;3. Communication system based on Modbus protocol and CAN bus is designed in this paper for the communication between underwater units and upper monitor;4. Sensor calibration experiment and field test are adopted in this paper, and these greatly improve the accuracy of monitoring parameters and the reliability of the system.Underwater monitoring device designed in this paper has been launched successfully and running normally underwater. Monitoring parameters are uploaded regularly to the upper monitor and stored in the database. Through the statistics and analysis on these parameters, we realize monitoring the state of the turbines. And this has provided valuable data and experience for better development and utilization of the tidal energy.