【作者】 席慧；

【导师】 谢刚；

【作者基本信息】 太原理工大学 ， 控制理论与控制工程， 2012， 硕士

【摘要】 随着可在生能源的逐渐枯竭,人们开始重视对新能源的开发与利用。风力发电作为新能源的主力军,近年来得到了快速的发展。直驱型风力发电系统由于具有能量转换率高,并网功率控制灵活等优点,成为最具发展前景的风力发电方式之一,受到科研人员的广泛关注。在直驱型风力发电系统中,全功率变流器将发电机与电网连接,把变频变压的能量转换为恒频恒压的能量,实现对发电机输出的电流、功率因素等的快速调节,并减小谐波对电网的污染。同时,对整个风力发电系统高效、稳定的运行起到非常积极的作用。因此,对变流器的有效控制是电能转换的核心,掌握这项技术,可以很好的促进我国风力发电事业的发展。本论文主要对直驱式风力发电系统的双PWM变流器的数学模型及其控制策略进行了研究,并通过仿真实验验证了研究理论的正确性。论文的具体研究内容如下：(1)论文首先对风力发电的研究现状进行了一定的介绍,重点详细阐述了直驱式变流器拓扑结构和控制技术,建立了永磁同步发电机、PwM整流器以及变流器直流环节的数学模型,为后面的研究打下了一定的基础。(2)根据所建立的数学模型,分别对机侧变流器和网侧变流器的控制策略进行了研究,机侧变流器采用转子磁场定向的矢量控制策略,网侧变流器采用电网电压定向的控制策略,实现了有功功率和无功功率的解耦控制；对控制系统的PI参数、网侧滤波电感、直流侧电容等参数进行了计算,为系统参数的选择提供了一定的参考；最后研究了当三相电网电压跌落时,直流侧应采取的保护措施。(3)在MATLAB/Simulink仿真平台上搭建了整个直驱型风力发电系统的仿真模型,分别对电网电压正常和电网电压跌落两种情况进行了仿真分析。仿真表明：在电网电压正常的情况下,所研究的控制策略可以实现最大功率追踪和保持直流电压的稳定；在电网电压跌落的情况下,直流侧电容会出现过电压情况,通过采取保护措施,可以很好的解决这一问题。更多还原

【Abstract】 As in the depletion of renewable energy, people began to pay attention to the development and utilization of new energy. Wind power as the main force of the new energy, has achieved rapid development in recent years. Due to the high rate of energy conversion and flexible network power control, direct-drive wind power generation system becomes one of the most promising wind power generations and obtains extensive attention from researchers.In the direct-drive wind power system, full-power converter connects generator and electric, variable frequency energy is converted to the constant frequency constant voltage energy, to achieve the rapid adjustment of generator output current and power factor and reduce the harmonic pollution on power. Meanwhile, it plays a very active role in the efficient and stable operation of the entire wind power generation system. Therefore, the effective control of the converter is the core of the power conversion; master the technology can promote the development of China’s wind power business.The paper main makes research on the mathematical model of dual PWM converter in the direct-drive wind power system and its control strategy, and verified the correctness of the theory of the study by simulation experiment. The specific content of the paper is as follows: Ⅰ. Firstly, the research make introduction on the current situation of wind power; focuses on the direct-drive inverter topology and control technology, build a mathematical model of permanent magnet synchronous generator, the PWM rectifier and the converter DC link, so laid a foundation for the later study.Ⅱ. According to the mathematical model, study respectively on the machine side converter and grid side converter control strategy. Machine-side converter use the rotor magnetic field oriented vector control strategy, Network-side converter use the grid voltage-oriented control strategy, decoupling control of active power and reactive power; Parameters such as the calculation of the PI parameters of the control system, the network side of the filter inductor, the DC side capacitance, provides the reference for the choice of system parameters; Finally, study the protection measures to be taken to the DC side when the three-phase power grid voltage drop.Ⅲ. Build a simulation model of the entire direct-drive wind power generation system on the MATLAB/Simulink simulation platform and make simulation analysis on two cases of normal grid voltage and grid voltage drop. Simulation results show that:In the case of normal grid voltage, the control strategy can achieve the maximum power point tracking and maintain the stability of the DC voltage; In the case of power grid voltage drop, DC capacitor will bring over voltage. By protective measures can solve this problem effectively.更多还原