Dynamic Characteristics of Wind Turbine Transmission System under Verying Wind Speed and Operation Control Conditions

2012 ◽  
Vol 48 (07) ◽  
pp. 1 ◽  
Author(s):  
QIN Datong
2021 ◽  
Vol 104 (3) ◽  
pp. 003685042110356
Author(s):  
Hexu Yang ◽  
Xiaopeng Li ◽  
Jinchi Xu ◽  
Zemin Yang ◽  
Renzhen Chen

According to the working characteristics of a 1.5 MW wind turbine planetary gear system under complex and random wind load, a two-parameter Weibull distribution model is used to describe the distribution of random wind speed, and the time-varying load caused by random wind speed is obtained. The nonlinear dynamic model of planetary gear transmission system is established by using the lumped parameter method, and the relative relations among various components are derived by using Lagrange method. Then, the relative relationship between the components is solved by Runge Kutta method. Considering the influence of random load and stiffness ratio on the planetary gear transmission system, the nonlinear dynamic response of cyclic load and random wind load on the transmission system is analyzed. The analysis results show that the variation of the stiffness ratio makes the planetary gear have abundant nonlinear dynamics behavior and the planetary gear can get rid of chaos and enter into stable periodic motion by changing the stiffness ratio properly on the premise of ensuring transmission efficiency. For the variable pitch wind turbine, the random change of external load increases the instability of the system.


2021 ◽  
pp. 1-7
Author(s):  
Sobhy Ghoneam ◽  
Ahmed Hamada ◽  
Taha S. Sherif

Abstract This paper presents a comprehensive study of the dynamic behavior of small vertical axis wind turbines (VAWTs) based on local fabricated Savonius VAWTs, which is suitable for countries that have moderate wind speed. The merits of this design are cleanliness, silent, start-up under low wind speed, independent wind directions, adaptability and ease of manufacturing. Also, this paper presents an experimental validation study for the optimized Savonius VAWT. Four verification test configurations of the optimized VAWT composite blades are designed, simulated and fabricated of Glass – Polyester with different stacking sequence layout for each. Modified mechanical parameters are introduced to improve the scalability, reliability, and accuracy of the developed models. Based on wind energy conversion system basics, aerodynamic characteristics (tip speed ratio (λ) and coefficient of power (Cp)), dynamic characteristics (natural frequencies and mode shapes) of Savonius-rotor models are presented and simulated within SOLIDWORKS Simulation 2020 software. The dynamic characteristics such as frequency, mode shape and damping factor are extensively investigated using Fast Fourier Transformer (FFT) analyzer. The results show that the role of composite material blades in improving the dynamic performance of a wind turbine is significant.


2013 ◽  
Vol 321-324 ◽  
pp. 9-12
Author(s):  
Wen Jun Yang ◽  
Hui Qun Yuan ◽  
Zhi Min Huang ◽  
Li Se Yang

Based on gear transmission system of 1.5MW wind turbine, dynamic characteristics are analyzed under the effect of both external and internal incentives. Using lumped parameter method, the dynamic model involving 6 degrees of freedom for every helical gear is established with taking the time-varying mesh stiffness and error into account. The results show that the transmission system is quasi-periodic under the operating speed, and the vibration direction of gear with a large amplitude is obtained. This study can be referred to the engineering applications.


Author(s):  
Huitao Chen ◽  
Xianhui Wang ◽  
Haichao Gao ◽  
Fan Yan

In order to study the dynamic characteristics of gear transmission system of wind turbine with random wind and the effect of random backlash on system stability, a stochastic volatility model is established to obtain the external excitation of gear transmission system of wind turbine. A dynamic model of system is set up with the consideration of gear time-varying mesh stiffness, transmission error and backlash. The dynamic behavior of system with random wind and the effect of random backlash on system stability are obtained using numerical method. The results show that: (1) The vibration displacement of system components has the similar trends with external excitation, and the higher the speed, the greater the vibration displacement. (2) Random backlash has a significantly influence on system stability. The instability of system decreases at first and then increases with the increase of mean backlash, and the stability of system decrease with the increase of standard deviation of backlash. The operation stability of a wind turbine will improve if select an appropriate gear backlash.


2011 ◽  
Vol 86 ◽  
pp. 518-522 ◽  
Author(s):  
Hui Tao Chen ◽  
Xiao Ling Wu ◽  
Da Tong Qin ◽  
Jun Yang ◽  
Zhi Gang Zhou

The effects of gear manufacturing error on the dynamic characteristics of planetary gear transmission system of wind turbine are studied in this paper. Firstly, the static transmission error combined with manufacturing error of the gear is deduced. Then, the nonlinear dynamic model of planetary gear transmission system of wind turbine is set up with the consideration of time-varying mesh stiffness, backlash and manufacturing error. Finally, the statistical characteristics of Vibration displacement response process of each component of planetary gear transmission system are obtained by simulation analysis of the planetary gear system of 1.5MW Semi-direct drive wind turbine with the consideration of the torque fluctuation caused by wind speed. The research results lay a foundation for reliability design and optimizing of gear transmission system of wind turbine.


Author(s):  
Aiqiang Zhang ◽  
Jing Wei ◽  
Datong Qin ◽  
Shaoshuai Hou ◽  
Teik C. Lim

Gravity is usually neglected in the dynamic modeling and analysis of the transmission system, especially in some relatively lightweight equipment. The wind turbine gearbox weight up to tens of tons or even hundreds of tons, and the effects of gravity have not been explored and quantified. In order to obtain accurate vibration response predictions to understand the coupled dynamic characteristics of the wind turbine gear transmission system, a comprehensive, fully coupled, dynamic model is established using the node finite element method with gravity considered. Both time-domain and frequency-domain dynamic responses are calculated using the precise integration method with various excitations being taken into account. The results indicate that gravity has a significant impact on the vibration equilibrium position of central floating components, but the changing trends are different. Gravity does not change the composition of the excitation frequency, but will have a certain impact on the distribution ratio of the frequency components. And the high frequency vibrations are hardly affected by gravity. In addition, the load sharing coefficient is greater when gravity is taken into account, both of internal gearing and external gearing system. When the planet gears have a certain position error in accordance with certain rules, the load sharing performance of the system will be better.


2011 ◽  
Vol 86 ◽  
pp. 653-657
Author(s):  
Zhi Gang Zhou ◽  
Da Tong Qin ◽  
Jun Yang ◽  
Hui Tao Chen

The sparse least squares support vector machines (SL-SVM) is used to simulate wind speed of real wind field, and time-varying wind load caused by stochastic wind speed is then obtained. A coupling gear-bearing dynamical model of planetary gear transmission system of wind turbine is built using lumped-parameter method, in which the varying wind load, time-vary mesh stiffness of gear pair and time-vary stiffness of rolling element bearing are taken into account. Numerical method is used to simulate the dynamic performance of planetary gear transmission of multibrid technology wind turbine (MTWT) with 1.5MW rated power, the vibration displacement responses of gears and dynamic meshing forces of gear pairs as well as nonlinear bearing forces in the transmission system are obtained, and the influence rules of external varying wind load on the vibration characteristics of transmission system of wind turbine are studied. The research results lay a foundation for dynamic performance optimization and reliability design of gear transmission system of wind turbine.


2020 ◽  
Vol 17 (2) ◽  
pp. 69-72
Author(s):  
V. Кауаn ◽  

The results of studies on possibility of increasing efficiency in the use of wind energy and improving the dynamic characteristics of Darrieus wind turbine with straight blades are described. It is shown how the values of torque on the rotor shaft may be optimized by controlling the orientation of the turbine blades relative to the oncoming flow. Control of blades was provided with a cylindrical track of the special form in plan. The track form allowed to establish optimum angle of attack on each site of blade circular trajectory. It allowed to increase power coefficient Cp by 1.5 times and to reduce wind speed at which there is self-start of the wind turbine


Sign in / Sign up

Export Citation Format

Share Document