【作者】 张纯明；

【导师】 姚兴佳；

【作者基本信息】 沈阳工业大学 ， 电工理论与新技术， 2011， 博士

【摘要】 随着世界风力发电技术的迅速发展,风电机组单机容量不断增大,风机变速变桨控制已经成为世界风电发展的主流。尤其是通过独立变桨控制来稳定发电机功率输出和减小机组动态载荷的控制策略更成为当前大型风电机组研发的关键。本文以国家科技部重大支撑专项“适应海、陆环境的双馈式变速恒频风电机组的研制”课题为依托,以3MW双馈变速恒频风力发电机组独立变桨距控制系统为研究对象,对独立变桨控制策略进行深入研究,进一步减小大型风电机组运行中的不平衡载荷,稳定发电机的功率输出。主要研究内容如下:首先,基于风机变桨控制理论和独立变桨控制模型,研究了基于叶根载荷坐标变换桨距角反馈线性化的独立变桨控制策略。在变速变桨距风机空气动力学和独立变桨运行原理基础上,深入分析了独立变桨控制的机构设置、风机风速特性和风机运行的动态载荷等问题,推导出独立变桨反馈线性化控制模型,设计出基于叶根载荷变换桨距角反馈线性化的独立变桨控制策略。该控制策略通过实时检测每个叶片的叶根载荷,以此来反映叶片和机组因风速变化引起的不平衡载荷,利用Coleman坐标变换理论将叶根载荷变换为桨距角反馈调节量,对风机桨叶进行单独控制。控制的主要目标是实时跟踪响应风速的变化,通过桨距角反馈调节,提高大型风电机组独立变桨系统的稳定性和快速性,减小由风切变、塔影效应和随机湍流等对机组造成的不平衡载荷。通过计算机仿真,结果表明:基于叶根载荷变换桨距角反馈线性化的独立变桨控制策略,能够快速响应风速的变化,实时调节风机桨叶,系统具有较强的稳定性和快速性,对减小风电机组的不平衡载荷效果明显。其次,研究设计了基于3MW风电机组线性参数变化(LPV)模型参考自适应的独立变桨系统整机控制策略。针对大型风电机组多输入、多输出的非线性耦合和独立变桨引起的附加控制载荷影响,应用线性参数变化LPV理论对风电机组风能转换系统多变量控制进行线性化,建立了风电机组独立变桨控制系统线性参数变化LPV模型。该模型以可测参数的缓慢变化来实时反应机组风能转换过程中的非线性,可以有效模拟风电机组的实际运行状况。以此,采用模型参考自适应控制理论设计出基于风电机组LPV模型参考自适应的独立变桨整机控制策略。通过对LPV模型参考自适应独立变桨控制和PI独立变桨控制计算机仿真比较,结果表明,采取LPV模型参考自适应控制的独立变桨系统输出转矩脉动相对平缓,幅值变化小,发电机输出功率稳定,传动系统的震动较小,输出效率较大,相对PI控制更具有优越性。最后,为了验证上述独立变桨控制的策略和仿真结果,设计了3MW双馈变速恒频风力发电机组独立变桨距半实物实验测试平台。通过对风电场和风机风况的实际模拟对独立变桨控制策略进行了试验研究。半实物实验平台中风电机组运行控制系统、电动变桨距执行机构、传感系统都是实物,而其它如风轮、塔架、发电机等都用GH公司的Bladed仿真软件来模拟,整个半实物实验台相当于一台独立变桨距风机。实验结果进一步验证了本文所研究的大型风电机组独立变桨控制策略的可行性和有效性。更多还原

【Abstract】 With the rapid development of wind power generation technology, the wind generator single capacity are continually increased, variable speed and pitch control technology has become the main trend in today’s wind power development. Especially, the control strategy of using individual pitch to stabilize the output power of generator and reduce load disturbance of wind turbine is the hot spot of large wind turbines research. Depend on National Key Technology R&D Program major project“Research and development of land and sea environment doubly fed variable speed constant frequency wind turbines”, this thesis studied the independent variable pitch control strategy on 3MW doubly fed variable speed constant frequency wind turbine independent variable pitch control system. The purpose is using independent variable pitch control to reduce the unbalanced load of wind turbine, stabilize the output power of generator. The major research works are summarized in the following:Firstly, according to wind turbine variable pitch control theory and independent variable pitch control wind turbine control model; independent variable pitch control theory based on blade root loading coordinate transformation pitch angle feedback linearization is studied. Based on the summary of variable speed and variable pitch wind turbine aerodynamics and operation principle, the thesis analyzed the problems such as structural establishment of independent variable pitch, wind turbine characteristics and dynamic loading of independent blade operating, derived independent variable pitch feedback linearization control model, designed independent variable pitch control strategy based on blade root loading variable pitch angle feedback linearization. By detected the blade root loading of each blade and using Coleman coordinate transformation theory to change blade root loading into pitch angle feedback adjustment, the strategy realized the independent control of wind turbine, the main purpose is to reduce the unbalanced loading to the wind turbine caused by wind shear, tower shadow and random turbulent. Compared with PI unified variable pitch control simulation exercises, the results illustrate, independent variable pitch control strategy based on blade root loading variable pitch angle feedback linearization can realized independent pitch control and has significant effect on reducing dynamic loading of wind turbine, pitch control system has better stability and faster response time.Then, the research designed independent variable pitch control strategy based on 3MV wind turbine LPV (linear parameter variable) model reference self-adaption. According to the non-linear couple of large wind turbine multi-input and multi-output and the extra control loading impact of independent variable pitch, the thesis used LPV theory to linearize the variable control of wind power transformation system in wind turbine, established the LPV model of wind turbine independent variable pitch control system. This model can be used to test the slowly change of parameters and realized the non-linearization in wind power transformation processes of wind turbine, can effectively simulated the operation situation of wind turbine. In addition, an independent variable pitch whole turbine control strategy based on wind turbine LPV model reference self-adaption is designed using model reference self-adaption control theory. Compared with the independent variable pitch system computer simulation between LPV model reference self-adaption control and PI control, the results illustrate, the independent variable pitch system using LPV model reference self-adaption control has more gentle torque pulsation output, with small amplitude change, generator output power is around rated power, transmission system has small shock and high output efficiency, and has better advantages than PI control.Finally, a 3MW wind turbine independent variable pitch semi-physical experiment platform is established to confirm the above independent variable pitch control strategy and simulation results. By simulated the typical wind field situation, independent variable pitch control strategy is tested. There are some entities in the semi- physical simulation experiment platform, such as wind turbines operating control system, electronic drive mechanism of variable pitch system and sensor system. Others such as wind wheel, tower and generators are using Bladed simulation software powered by GH Company to simulate; the whole semi-physical simulation platform can be regard as a real variable speed variable pitch turbine. The test data shows that the individual variable pitch control strategy of large-scale wind turbine is feasible and effective.更多还原