Performance Of Wind Turbine System Research Articles

Performance of wind turbine system based on a brushless doubly fed reluctance generator and a six pulse bridge cycloconverter

In this paper, a variable speed wind energy conversion system (WECS) made with a six pulse bridge cycloconverter and a brushless doubly fed reluctance generator (BDFRG) is investigated. The novelty of the proposed work is to use a brushless doubly fed reluctance generator and a six pulses cycloconverter for working in high power and for reducing the cost, also the proposed work use a maximum power point tracking algorithm to capture the optimal power available in the wind in order to increase the efficiency of the system. The power control of this system is applied, to capture the maximum power from the wind by using a maximum power point tracking (MPPT) control technique, to achieve the independent control of the active and reactive powers exchanged between the wind generator and the grid, also to test the possibility to operate in two quadrant modes (subsynchronous and supersynchronous modes). The dynamic modeling equations that describe the suggested system are presented here. The results of the simulation are shown in order to illustrate the performance and efficiency of this system.

Study the Response Of The Wind Turbine System under Realistic Working Conditions Using Simulink

In recent years, there has been a very rapid development in the field of clean energy due to the huge increase in the demand, which prompted the manufacturers and the designers to increase the efficiency and operating life of the energy systems and especially for wind turbine. It can be considered that the control unit is the main key of the wind turbines. Consequently, it’s essential to understanding the working principle of this unit and spotlight on the factors which influence significantly on the performance of wind turbine system. Simulink technique is proposed to find the response of the wind turbine system under different working conditions. In this paper, it was investigated the influence of the rotational speed, type of generator on the response of the wind turbine system.

Aerodynamic performance and wind-induced effect of large-scale wind turbine system under yaw and wind-rain combination action

Blade yaw will change aerodynamic performance of large-scale wind turbine structure, especially under rainstorm conditions. Structural responses and stability of large-scale wind turbine system during rainstorm are more complicated due to the impact force of rainstorm on the structural surface and its influences on the incoming turbulence. In this study, the 5 MW wind turbine tower-blade system which was developed by Nanjing University of Aeronautics and Astronautics (NUAA) was used as the research object. Firstly, the surrounding wind field of the 5 MW wind turbine tower-blade system under different yaw angles (0°, 5°, 10°, 20°, 30° and 45°) was simulated by the computational fluid dynamics (CFD) technology based on the wind-rain two-way coupling algorithm. Secondly, the wind-rain coupling synchronous iteration was carried out by adding the discrete phase model (DPM). Based on numerical simulation results, the influencing law of yaw angle on wind-driven rainfall, additional acting force of raindrops and rain-induced pressure coefficient was discussed. The velocity flow line, turbulence energy strength, raindrop running speed and trajectory action mechanism on the structural surface in wind-rain coupling field was disclosed. Moreover, the distribution laws and fitting formula of wind-rain equivalent pressure coefficient under different yaw angles were constructed. Finally, large-scale wind turbine tower-blade coupling model under different yaw angles was constructed by combining the finite element method. Structural responses, buckling stability and ultimate bearing capacity of the large-scale wind turbine system with considerations to different yaw angles under wind condition and wind-rain condition were discussed. Results demonstrated that yaw angle can affect aerodynamic force and comprehensive stress performance of the wind turbine system significantly. The wind-rain load enhances structural responses of the system, and decreases the overall buckling stability and ultimate bearing capacity of the wind turbine. Main conclusions not only can provide references for accurate load evaluation under extreme complex conditions, but also are conducive to deepen understandings on the action mechanism of wind-rain load.

Modeling and Implementation of MPPT based Wind Energy System Using Cuckoo Search

This paper presents adjustable speed generators for wind turbines. In order to improve the potential and performance of wind turbine system this paper proposes a concept DFIG. Generally wind nature is not fixed it varies linearly w.r.t time, hence, a MPPT controller is proposed in this paper. This paper presents the DFIG wind energy system. A Control strategy implemented and controlled by framing rotor reference frame axis in terms of direct and quadrature axis coordinates. A PI based RSC and GSC controllers are introduced to control the power through the wind system to grid. This proposed model is implemented and verified by using Matlab/Simulink.

Analysis of the effect of blade positions on the aerodynamic performances of wind turbine tower-blade system in halt states

The unsteady flow field disturbance between the blades and tower is one of the primary factors affecting the aerodynamic performance of wind turbine. Based on the research object of a 3MW horizontal axis wind turbine which was developed independently by Nanjing University of Aeronautics and Astronautics, numerical simulation on the aerodynamic performance of wind turbine system in halt state with blades in different position was conducted using large eddy simulation (LES) method. Based on the 3D unsteady numerical simulation results in a total of eight conditions (determined by the relative position with the tower during the complete rotation process of the blade), the characteristics of wind pressure distributions of the wind turbine system and action mechanism of surrounding flow field were analysed. The effect of different position of blades on the aerodynamic performance of wind turbine in halt state as well as the disturbance effect was evaluated. Results of the study showed that the halt position of blades had significant effect on the wind pressure distribution of the wind turbine system as well as the characteristics of flow around. Relevant conclusions from this study provided reference for the wind-resistant design of large scale wind turbine system in different halt states.

Dynamic characteristics of gear box with PGT for wind turbine

Abstract: Gear box is the most important transmission device in wind turbines. The dynamic characteristics of gear box will directly influence the performance of wind turbine system, such as wind power conversion efficiency, weight lighten/power density and so on. This paper introduced the configurations of gear box in wind turbines, and summarized that planetary gear train (PGT) is most widely used gear box. Then, a nonlinear dynamic model coupled torsional translational degree of freedom is presented for a PGT with three planet gears, in consideration of manufacture and assembly errors and gear elastic deformation. By using the dynamic model, a single stage gear box (a PGT) in a wind turbine system is taken as a case study to discuss its dynamic characteristics, such as vibration characteristic, and load sharing characteristic among the planet gears, affected by support stiffness, manufacture and assembly errors. The work will provide a worthy reference for the wind turbine gear box design.

풍력 블레이드의 결빙에 의한 공력특성 및 성능 변화

추운 기후에서 운영되는 풍력터빈 시스템의 표면에 발생한 결빙으로 인하여 공기역학적 성능이 크게 저하될 수 있다. 이러한 결빙은 양력감소 및 항력증가를 야기하고, 발전효율에 부정적인 영향을 미치게 된다. 이로 인하여 풍력발전기의 성능저하 또는 과부하, 무게중심의 변화에 따른 과도진동, 결빙파편이 지상으로 떨어질 경우의 안전성 문제, 계기의 결빙으로 인한 계기 측정오차, 최악의 경우 풍력 시스템 정지 등의 문제가 발생한다. 본 연구에서는 결빙증식이 풍력 발전기의 공력특성에 미치는 영향을 CFD 기법을 이용해 분석하였다. 또한 결빙증식 결과를 바탕으로 BEM 기법을 적용시켜 삼차원 블레이드에 대한 공력성능을 계산하였다. 결빙의 두께는 상대적인 속도차이에 의해 블레이드 중심에서 끝단으로 갈수록 증가함을 알 수 있었고, 공기의 속도가 결빙증식에 미치는 주요 인자임을 확인하였다. A significant degradation in the aerodynamic performance of wind turbine system can occur by ice accretion on the surface of blades operated in cold climate. The ice accretion can result in performance loss, overloading due to delayed stall, excessive vibration associated with mass imbalance, ice shedding, instrumental measurement errors, and, in worst case, wind turbine system shutdown. In this study, the effects of ice accretions on the aerodynamic characteristics of wind turbine blade sections are investigated on the basis of modern CFD method. In addition, the computational results are used to predict the performance of three-dimensional wind turbine blade system through the blade element momentum method. It is shown that the thickness of ice accretion increases from the root to the tip and the effects of icing conditions such as relative wind velocity play significant role in the shape of ice accretion.