【作者】 刘向向；

【导师】 王奔；

【作者基本信息】 西南交通大学 ， 电机与电器， 2013， 硕士

【摘要】 随着全世界范围内的能源危机日益严重,人们逐渐将目光转向了新能源发电。风能作为一种清洁、环保、利用方便并且储存量巨大的可再生能源,受到了广泛关注,风力发电技术在世界各国得到了迅速发展。在各种变速恒频(VSCF)风力发电系统中,直驱永磁同步风力发电机组具有结构简单、不需要升速齿轮箱、不存在电刷和滑环、机组运行的稳定性和可靠性较高等优点,成为了当前最主要的发电方式。本文在了解了风力发电的研究意义和国内外研究现状以及直驱永磁同步风力发电机的结构特点的基础上,以直驱永磁同步风力发电机为研究对象,对其三种并网电路的优缺点进行了比较,选择采用双PWM变流器作为它的并网电路。推导出了永磁同步发电机(PMSG)在dq坐标系下的非线性数学模型。采用逆系统方法、变结构控制理论以及转子磁链定向矢量控制相结合的方法设计了发电机侧变流器的变结构控制器；采用电网电压定向矢量控制方法设计了电网侧变流器的PI控制器。搭建了仿真模型,并通过仿真验证了该控制策略可实现发电机输出有功功率的准确控制、并网有功功率和无功功率独立调节、变速恒频发电运行以及双PWM变流器直流侧电压稳定控制。变结构控制与PI控制相比,动态响应速度更快、鲁棒性更好。考虑到风电场输出功率的波动性、间隙性严重影响了电网的稳定运行,为平抑其输出功率波动,提高其并网运行稳定性,选择了在风电场并网母线位置集中配置了钒电池(VRB)储能系统。采用双向AC/DC变流器作为VRB储能系统的功率调节器,并采用非线性控制方法、变结构控制理论以及电网电压定向矢量控制相结合的方法设计了VRB储能系统的闭环控制器。搭建了仿真模型,仿真验证了风速变化时,利用该控制策略,VRB储能系统能够通过快速充放电,平抑风电场输出的功率波动,并且变结构控制的效果优于PI控制；VRB储能系统输出的有功和无功功率可进行独立调节,系统动态性能良好。更多还原

【Abstract】 With the growing worldwide energy crisis, people are gradually turning to new energy generation. Wind energy has attracted widespread attention as a clean、、 environmentally friendly、using convenient and huge storage capacity of renewable energy. Wind power technology has been the rapid development in the countries all over the world. A direct-drive permanent magnet synchronous wind turbine has become the main way of power generation in various VSCF wind power generation systems and it has a simple structure、does not need the liter-speed gearbox、does not exist the brush and slip ring unit、has high operation stability and reliability.In this paper, the significance of research and research status of the wind power generation as well as the structural features of direct-drive permanent magnet synchronous wind turbine have been understood, direct-drive permanent magnet synchronous wind turbine is used as the research object and comparing the advantages and disadvantages of its three kinds grid-connected circuit as well as the dual PWM converter is used as the main grid-connected circuit for it. The nonlinear mathematical model of permanent magnet synchronous generator in dq coordinate system is deduced. A control strategy is proposed to design the variable structure controller of the generator-side converter, which combines the inverse system method, the variable structure control theory and the rotor flux oriented vector control method, using grid voltage oriented vector control method to design the PI controller of the grid side converter. A simulation model is built. The simulation results indicate that using the proposed control strategy, the accurate control of active power output of PMSG, independent adjust of grid-connected active and reactive power, variable speed constant frequency (VSCF) power generation as well as stability control of dual PWM converter DC side voltage can be achieved. Compared with PI control, variable structure control shows quick dynamic performances and good robustness.Considering the fluctuation and intermission of wind farm output power seriously affect the stable operation of a grid. A vanadium redox flow battery (VRB) energy storage system is equipped at the grid bus of wind farm in order to smooth the output power and improve the stability of grid-connected wind farm. A bi-directional AC/DC converter is used as the power regulator of VRB energy storage system. A control strategy is proposed to design the closed-loop controller of energy storage system, which combines the nonlinear control method、the variable structure control theory and the grid voltage oriented vector control method. A simulation model is built. Simulation results show that using the proposed control strategy, the vanadium battery energy storage system can fast charge and discharge to smooth the fluctuation of wind farm output power when the wind speed rapidly changes, variable structure controller shows better dynamic performances when compared it with PI controller; the independent adjusting of the active and reactive power of VRB energy storage system output can be achieved, and the dynamic performance of system is good.更多还原