风力发电机多域物理建模方法及独立变桨模糊控制器优化研究

针对独立变桨风力发电机,分析了风力发电机运行原理,基于以上原理在Matlab下分别建立了1.5MW独立变桨风力发电机的监测控制系统、独立变桨距控制系统、偏航控制系统、液压执行器系统和电网系统的物理模型,设计了独立变桨距控制模糊PI控制器,与传统PI控制器进行了仿真对比。仿真结果表明了该物理模型的正确性,对比结果表明,模糊PI控制器不仅能提高节距角跟踪精度而且能够稳定输出电压和输出功率,同时也减小了拍打震动和桨叶载荷。     

漂浮式海上风力发电机组独立变桨距控制技术研究

主要研究了漂浮式海上风力发电机组的独立变桨距控制技术。首先概述了当前海上风电的发展情况,重点介绍漂浮式海上风力发电机组,分析了漂浮式平台的流体动力学和运动学特征,建立了平台的模型方程。借鉴陆上风力发电机组独立变桨距控制器的控制策略,将平台的纵摇、艏摇和发电机的输出功率作为变桨距控制器的控制目标,针对风力发电机的非线性设计了专家PID控制器,利用d-q坐标变换技术将控制量分配到3个桨叶。为了验证控制器的可行性,在国外成熟的风力发电机非线性模型FAST上进行仿真试验,将结果与不对平台运动进行控制时和采用统一变桨距控制器时的结果进行对比,对比结果表明独立变桨距技术能有效减小平台的纵摇运动,并且对输出功率的影响较小。     

遗传算法在变桨距风力发电控制系统中的应用

介绍了遗传算法的基本原理,讨论了一种应用遗传算法和模糊理论计算风力发电机变桨距控制器的方法,该方法利用遗传算法简单高效的寻优特点对模糊控制器的结构和参数进行优化设计。仿真结果表明,应用该方法设计的控制器具有很好的控制精度和动态特性,可应用于大型风力发机变桨距控制系统。     

风力发电机组并网控制器

该文介绍一种大中型风力发电机并网运行的控制器，它具有，性能稳定、抗干扰能力强的特点．，能完成数据采样、显示及实时监控的任务．文章以ＦＤ１６—７５ｋＷＡ网型风力发电机的并网运行控制为例，详细说明控制器的软硬件设计和现场投运情况．     

KF—100型风力发电机充放电控制器

FK—100型风力发电机充放电控制器,是使用100瓦风力发电机及蓄电池供电时所必备的配套产品,风力发电机为间歇工作的电源。连续供电,需备有蓄电池,而蓄电池无此控制器,则极易因电池过充过放电缩短使用寿命。本控制器能自动控制充电放电,以保护电池,     

可编程控制器实现风力发电机安全运行的处理方法

针对５５ｋＷ风力发电机对控系统特殊要求，结合可编程序控制器的性能特点，利用Ｃ６０Ｐ型可编程序控制器成功地实现了国产中型风力发电机控制系统的长时间安全运行。     

浓缩风能型风力发电机迎风自动控制系统

风力发电机的迎风控制对于保证其正常发电十分重要。根据浓缩风能型风力发电机的形体结构 ,设计了由风向标、PLC可编程控制器、小型直流继电器、直流减速电动机、蜗轮蜗杆减速机等组成的闭环控制系统。实验结果表明整个系统可在风向变化超过± 15°时自动迎风 ,达到了设计要求。在程序设计中考虑了电缆缠结及解缆 ,可以使风电场管理人员在较长的时期内不必检查电缆缠结情况 ,简化了风力发电机的维护过程。为浓缩风能型风力发电机组向中、大型并网发电机组发展奠定了基础     

国产200kW风力发电机微机控制器

国产２００ｋＷ风力发电机微机控制器高海建目前国外大中型风力发电机普遍采用微机控制，实现风力机群自动控制，无人值守。该微机控制器是以８０３１单片机为主芯片的控制系统，可实现无人值守，自动记录数据，故障判断，汉字显示和机群集中管理。１系统硬件结构该系统采...     

带有RCC的异步风力发电机系统的特性分析

介绍了带有转子电流控制器（RCC）的变桨距调节异步风力发电机系统的基本原理及其控制策略。基于Saber仿真软件，建立了变桨距风力机、绕线式异步发电饥、转子电流控制器以及风速等的仿真模型，并以此为基础深入研究了该类风力发电机系统的运行特性。仿真分析表明，引入转子电流控制可以明显改善发电机的输出电能品质，降低变桨距风力机的调节频率，延长变桨距机构的使用寿命。制作了一套7．5kW模拟异步风力发电机的RCC系统，对带有RCC的异步风力发电机系统进行了模拟实验研究。     

小型风力发电机组优化控制策略与实验研究

提出一种小型风力发电机组功率的优化控制策略.根据选定的300 W/24 V永磁发电机,使用Wilson叶片设计计算模型,应用MATLAB语言设计了300 W风机叶片;并针对现有风机控制系统中将控制器的设计与叶片、电机的匹配特性彼此孤立、分离的现象,设计出与风力发电机的电机、叶片相互匹配的控制器.在风洞试验中测试了样机在8、10 、12 、15 m/s等风速一定条件下,功率随系统电压的变化规律,当降低系统电压时,风机输出功率会一直下降,在此过程中并没有出现功率增加的现象,也就充分证明了工作在峰前区域的风力发电机,当风速大于额定风速时,控制系统可以通过减小接入系统的负载电阻值来控制其功率.这对研究小型风力发电系统的可控性、可靠性和耐久性有一定的指导意义和实用价值.     

大型海上风电机组变桨距PID控制策略研究

文章针对大型海上风机的叶片具有较大惯性的问题,分析了传统变桨距PI控制器的不足,从而设计出带有超前环节的变桨距PID控制器,其能改善因惯性较大而导致的不良控制效果,并通过典型工况的仿真计算及性能分析,表明PID控制器的整体性能优于PI控制器,不仅具有稳定风轮转速、减轻风机振动的优点,还降低了风机的极限载荷水平,从而在保证安全性的基础上降低了机组成本。     

Identification in closed‐loop operation of models for collective pitch robust controller design

To achieve load reduction and power optimization, wind turbine controllers design requires the availability of reliable control‐oriented linear models. These are needed for model‐based controller design. Model identification of wind turbine while operating in closed loop is an appropriate solution that has recently shown its capabilities when linear time‐invariant controllers and complicated control structures are present. However, the collective pitch control loop, one of the most important wind turbine loops, uses non‐linear controllers. Typically, this non‐linear controller is a combination of a linear controller and a gain scheduling. This paper presents a new algorithm for identification in closed‐loop operation that allows the use of this kind of non‐linear controllers. The algorithm is applied for identification the collective pitch demand to generator speed of a wind turbine at various operating points. The obtained models are presented and discussed from a control point of view. The validity of these models is illustrated by their use for the design of a linear fix robust controller. The performance based on simulation data of this linear controller is similar to that obtained with simulations based on a linear controller with gain scheduling, but its design and implementation is much simpler. Copyright © 2012 John Wiley & Sons, Ltd.     

A fuzzy logic pitch angle controller for power system stabilization

In this article the design of a fuzzy logic pitch angle controller for a fixed speed, active‐stall wind turbine, which is used for power system stabilization, is presented. The system to be controlled, which is the wind turbine and the power system to which the turbine is connected, is described. The advantages of fuzzy logic control when applied to large‐signal control of active‐stall wind turbines are outlined. The general steps of the design process for a fuzzy logic controller, including definition of the controller inputs, set‐up of the fuzzy rules and the method of defuzzification, are described. The performance of the controller is assessed by simulation, where the wind turbine's task is to dampen power system oscillations. In the scenario simulated for this work, the wind turbine has to ride through a transient short‐circuit fault and subsequently contribute to the damping of the grid frequency oscillations that are caused by the transient fault. It is concluded that the fuzzy logic controller enables the wind turbine to dampen power system oscillations. It is also concluded that, owing to the inherent non‐linearities in a wind turbine and the unpredictability of the whole system, the fuzzy logic controller is very suitable for this application. Copyright © 2006 John Wiley &Sons, Ltd.     

Simulating Feedback Linearization control of wind turbines using high‐order models

As wind turbines are becoming larger, wind turbine control must now encompass load control objectives as well as power and speed control to achieve a low cost of energy. Due to the inherent non‐linearities in a wind turbine system, the use of non‐linear model‐based controllers has the potential to increase control performance. A non‐linear feedback linearization controller with an Extended Kalman Filter is successfully used to control a FAST model of the controls advanced research turbine with active blade, tower and drive‐train dynamics in above rated wind conditions. The controller exhibits reductions in low speed shaft fatigue damage equivalent loads, power regulation and speed regulation when compared to a Gain Scheduled Proportional Integral controller, designed for speed regulation alone. The feedback linearization controller shows better rotor speed regulation than a Linear Quadratic Regulator (LQR) at close to rated wind speeds, but poorer rotor speed regulation at higher wind speeds. This is due to modeling inaccuracies and the addition of unmodeled dynamics during simulation. Similar performance between the feedback linearization controller and the LQR in reducing drive‐train fatigue damage and power regulation is observed. Improvements in control performance may be achieved through increasing the accuracy of the non‐linear model used for controller design. Copyright © 2009 John Wiley & Sons, Ltd.     

风电机组电动变桨距伺服系统的研究

基于非线性PI理论,针对风力发电机组电动变桨距伺服系统中执行电机的非线性特性,提出了一种新的非线性控制方法。该方法基于对象的非线性模型,通过简单的非线性变换,把串励直流电机控制器的设计简化为线性系统问题。通过对变桨距电机负载所受驱动力进行了详细分析,进一步设计了控制器,在Matlab/Simulink环境下进行的数字仿真表明,此伺服系统具有良好的动态性能。     

一种新型聚能-遮蔽型立轴风力机

提出了一种适合任意风向的新型聚能-遮蔽型立轴风力机,并应用计算流体力学方法,对这种风力机的气动性能进行了数值模拟.研究表明:这种新型立轴风力机比传统的立轴风力机的风能利用率有显著提高.此外,该文还采用了正交优化设计方法,对这种立轴风力机的结构参数进行了优化设计,得到了一组最优的设计参数,该最优设计参数下风力机的风能利用率达37%.     

Transient and dynamic control of a variable speed wind turbine with synchronous generator

In this article, a controller for dynamic and transient control of a variable speed wind turbine with a full‐scale converter‐connected high‐speed synchronous generator is presented. First, the phenomenon of drive train oscillations in wind turbines with full‐scale converter‐connected generators is discussed. Based on this discussion, a controller is presented that dampens these oscillations without impacting on the power that the wind turbine injects into the grid. Since wind turbines are increasingly demanded to take over power system stabilizing and control tasks, the presented wind turbine design is further enhanced to support the grid in transient grid events. A controller is designed that allows the wind turbine to ride through transient grid faults. Since such faults often cause power system oscillations, another controller is added that enables the turbine to participate in the damping of such oscillations. It is concluded that the controllers presented keep the wind turbine stable under any operating conditions, and that they are capable of adding substantial damping to the power system. Copyright © 2007 John Wiley & Sons, Ltd.     

The effect of timescales on wind farm power variability with nonlinear model predictive control

Model predictive control techniques enable operators to balance multiple objectives in large wind farms, but the controller design depends on modeling effects that propagate at different timescales. This paper uses nonlinear model predictive control to investigate how wind farm power variability can be reduced both by varying ratios of three timescales impacting the system control and by inclusion of a power variability minimization measure in the controller objective function. Tests were conducted to assess how different timescale ratios affect the average farm power and power variability. Power variability measures are shown to be sensitive to the ratio of the incident wind period and the turbine time delay, particularly for cases with dominant incident wind frequencies. The average farm power increases in a series of steps as the controller time horizon increases, which corresponds to time horizon values required for wakes disturbances to propagate to downstream turbines. A second set of tests was conducted in which various measures of power variability were incorporated into the controller objective function and shown to yield significant reductions in farm power variability without significant reductions in farm power output. The controller was found to utilize two different approaches for achieving power variability reduction depending on the formulation of the controller objective function. These results have important implications for the design and operation of wind power plants, including the importance of considering the frequency components of wind during turbine siting and the potential to reduce power variability through the use of farm‐level coordinated control. Copyright © 2017 John Wiley & Sons, Ltd.     

An analytical frequency-domain model of aerodynamic mass and damping of floating wind turbines

The fore-aft motion of the rotor-nacelle assembly (RNA) of a rotating floating wind turbine (FWT) can cause an oscillation in aerodynamic thrust, which may be equivalently treated as frequency-dependent aerodynamic mass and damping effects. In this study, an explicit frequency-domain analytical model is proposed to calculate the equivalent aerodynamic mass and damping of FWTs, with proper linearization of control system. Assuming that an FWT operates under steady wind conditions and a forced oscillation is exerted at the RNA along the wind direction, the thrust fluctuations are equivalently represented by the force and moment acting on the nacelle instead of pure aerodynamic loads. Based on the thrust oscillation expression, equivalent aerodynamic mass and damping are derived analytically. After verifying the model by numerical comparison, it is used to demonstrate equivalent aerodynamic mass and damping of three wind turbines (5–15 MW). Effects of wind turbine up-scaling and controller dynamics are addressed. Results show that equivalent aerodynamic mass and damping present a nonlinear characteristic with oscillation frequency in the below-rated region, while the relationship is close to linear for higher wind speeds. The effect of wind turbine up-scaling has a visible impact on equivalent aerodynamic mass and damping, especially at near-rated wind speed. Controller gains affect equivalent aerodynamic mass and damping and should be tuned reasonably in the controller design for FWTs. Outcomes of our study can be used to establish a frequency-domain coupled model of FWTs and are beneficial for conceptual design and parameter optimization of the platform of FWTs.