Study On Vibration Response Of A Floating Tidal Powergeneration Device

In the process of power generation,the tidal power generation device will be subject to external excitation such as turbine,generator and tidal current,under these external excitation,the tidal power generation device will produce different degrees of vibration,and the long-term vibration will not only produce the structure fatigue damage,but also affect the normal use of various types of equipment on the tidal power generation.Therefore,it is very important to study the vibration characteristics of the tidal power generation devicein order to ensure the long-term stable operation of it.In this paper,a floating type tidal power generation device which uses the barge as carrier and equipped with vertical shaft turbine is proposed,and its vibration characteristicswere studied.The work of this paper is as follows:1?A three-dimensional finite element model of floating tidal power generation device is established,the modal analysis is carried out after obtaining the attached water quality,the influence of the attached water quality on the natural frequency of the tidal power generation device is compared,and the natural frequency calculation result is compared with the known excitation frequency,the results show that the vibration of the tidal power generation is a low frequency vibration,the natural frequency of the power generation device effectively avoids the tidal load and the turbine load frequency and there is no resonance phenomenon.2?The dynamic load of the turbine is calculated,and then the vibration force is sinusoidal by the Fourier series expansion,the motion force of the turbine blade is calculated and analyzed in detail,finally the results of vibration response of each position of the tidal power generation are obtained by transient response analysis.3?Unfolded real ship vibration test of the tidal power generation device,measured the acceleration response curve at the critical position and got the displacement response curve by quadratic integration,then compared the results with the numerical simulation after the measurement data processing,got the error at the location of the test points are in acceptable rangeand both have the same conclusion,the reduction of the speed makes the excitation force decreases,the displacement response value becomes smaller,and finally completed the tidal current power plant vibration evaluation,the evaluation area of each test point is in the favorable evaluation area of vibration,is in line with the actual engineering standards.4?The numerical simulation of the mooring system of the tidal power generation is carried out by the software of AQWA,based on the time domain analysis,the response value of each mooring chain is obtained under the condition of different environmental load incidence angle,.the simulation results show that: The normal working sea conditions and the survival of the sea conditions,the incident angle of 90° corresponds to the most dangerous horizontal wave conditions;under different environmental loads,the equivalent safety factor of each mooring chain is more than 1.67;the tension reserves of each mooring chain meet the specifications and meet the actual engineering requirements.