【作者】 马丽；

【导师】 刘军； 霍连文；

【作者基本信息】 西安理工大学 ， 控制工程， 2016， 硕士

【摘要】 能源是人类赖以生存和发展的重要物质基础之一。在能源推动社会进步的过程中,化石能源也在日趋枯竭,同时长期大量使用煤炭、石油、天然气等导致的气候、生态环境问题也日益突出。风能作为一种清洁且开发技术相对成熟的可再生能源,发展前景广阔。目前,直驱式永磁同步风力发电系统由于传动系统结构简单、运行可靠、发电效率高等优点得到广泛应用。首先,本文建立了直驱式永磁同步风力发电系统的数学模型,对直驱式永磁同步风力发电系统工作原理和矢量控制策略进行了分析。由于直驱式永磁同步风力发电系统功率存在损耗,导致基于功率反馈的传统的最大风能跟踪控制策略在实际应用中不能给定准确的最大功率,从而影响了系统风能吸收效率。本文建立了考虑铜耗、铁耗、机械损耗和杂散损耗的永磁同步风力发电机的模型,通过计算损耗的转矩值,在传统功率反馈控制的基础上,研究了考虑损耗转矩的最佳电流给定的最大风能跟踪控制,从而提高风能捕获的准确性。其次,由于永磁同步风力发电系统是一个多变量、非线性、强耦合、时变的复杂系统,难以建立其精确的数学模型,本文以桨距角的变化量作为模糊控制器的输出,设计了基于模糊控制理论的变桨距控制器。考虑到实际的变桨距执行机构存在动作滞后,同时变桨距的速度也是有限的,当风速包含有阵风或高频变化分量时,仅调节风力机的桨距角难以达到预期的效果,风力发电机的输出功率和机组转速仍有明显波动。而采用传统的有功功率控制策略,风力发电机输出有功功率时也会产生波动,这对电网安全稳定的运行产生较大的影响。因此,提出了在全风速范围内结合风力发电机变桨控制和发电机变速控制的有功功率平滑控制策略,即全风速范围调节桨距角,并兼顾功率平滑性和利用率达到了风机输出功率平滑的要求。最后,本文在Matlab/Simulink平台上建立了直驱永磁同步风力发电系统的仿真模型,验证了控制策略的有效性和正确性。更多还原

【Abstract】 Energy is one of the important material basis for human survival and development.In the process of social progress,resources are increasingly depleted,at the same time,climate,ecological and environmental problems are caused by a long-term use of coal,oil,natural gas and other fossil resources are worse.Wind energy as a clean and development technology is relatively mature renewable energy,has broad prospects for development.At present,direct drive permanent magnet synchronous wind power generation system has been widely used because of its simple drive system,reliable operation,high power efficiency and so on.First of all,the mathematical model of direct drive permanent magnet synchronous wind power generation system is established,and the operation principle and vector control strategy of direct drive permanent magnet synchronous wind power generation system are analyzed.Due to the power loss of the system,the traditional maximum wind energy tracking control strategy based on power feedback cannot be given the accurate maximum power in the practical application,which can affect the efficiency of the system.In this paper,considering the copper loss,iron loss,mechanical loss and stray loss in the permanent magnet synchronous wind generator model,calculating the value of the loss,based on the traditional power feedback control,studying the maximum wind energy tracking control is given the best current considered loss torque,so as to improve the wind energy capture efficiency.Secondly,due to the wind power generation system is a complex system with multi variable,nonlinear,strong coupling,time-varying;it is difficult to establish an accurate mathematical model.This paper uses the variation of the pitch angle as the output of the fuzzy controller,designs a variable pitch controller based on the fuzzy control theory has a strong anti-interference ability.Considering the actual pitch actuator has delayed action.At the same time the speed of the variable pitch is limited,when the wind speed comprises a gust of wind or high-frequency changes,only adjusting the pitch angle of the wind turbine is difficult to achieve the expected effect,wind generator output power and rotating speed of the unit still fluctuates significantly.By using the traditional active power control strategy,the output power of the wind power generator can fluctuate,which has a large disturbance to the safe and stable operation of the power grid.So,the active power smoothing control strategy is proposed,which combines the variable pitch control and variable speed control of wind turbines in the full range of wind speed.Finally,the simulation model of the direct drive permanent magnet synchronous windpower generation system is established on the Matlab/Simulink platform,which verifies the effectiveness and correctness of the control strategy.更多还原