Dynamic Analysis Of The Vertical-axis Tidal Current Turbine

The vertical-axis tidal current turbine is a conversion device of ocean current energy,which is studied extensively in recent years. This paper completes the mechanism design ofthe2×300kW vertical-axis tidal current turbine, analyzes the mechanism dynamics,hydrodynamic and structure dynamics of the vertical-axis tidal current turbine, and verifiesthe feasibility of ocean current energy conversion of the vertical-axis tidal current turbine.Base on the typical structure of the vertical-axis tidal current turbine, hydrodynamicsproperty and the power generation technical characteristics of the tidal turbine, completing themechanism design of the vertical-axis tidal current turbine, establishing the3D solid model ofthe vertical-axis tidal current turbine.The transmission system dynamics of the vertical-axis tidal current turbine is analyzed.Based on the transmission system dynamics characteristics of the vertical-axis tidal currentturbine, establish the dynamics equations of the subsystems like impeller, gear transmissionsystem and generator, building transmission system dynamics model of the vertical-axis tidalcurrent turbine on the basis of the rigid shafting and the flexible shafting, and simulating it inideal flow velocities by MATLAB/SIMULINK software. The transmission system dynamiccharacteristic of the tidal turbine was analysis by the software.The hydrodynamics of the vertical-axis tidal current turbine is analyzed. Obtaining theexternal load function of the vertical-axis tidal current turbine in the actual measuredvelocities by analyzing its motion and stress, this lays the foundation for the harmonicresponse analysis of the whole system of the vertical-axis tidal current turbine. The outputcharacteristics of the tidal turbine in the actual measured velocities further verifies thefeasibility of the vertical-axis tidal current turbine mechanism model.Establishing the finite element simulation model for modal analysis of the increaser andthe whole tidal turbine by reasonable structure simplification, calculate the anterior10ranksof natural frequencies and corresponding mode shapes of increaser and the anterior20ranksof natural frequencies and corresponding mode shapes of the whole tidal current turbine bymodel analysis, the modal analysis results show that the natural frequency of the turbine isaway from the frequencies of tidal current load, impeller load and generator rotor load,implying the inexistence of the resonance phenomenon in this turbine. Analyze the dynamicresponse of the vertical-axis tidal current turbine under the load in the external loads, impellerand rotor eccentric load by the mode superposition method, and further validate the rationality of the vertical-axis tidal current turbine mechanism model. Furthermore, propose theapproach of strengthen the weak part of the structure during the structure design of thevertical-axis tidal current turbine.