【作者】 董钦；

【导师】 苏虎；

【作者基本信息】 西南交通大学 ， 电气工程， 2011， 硕士

【摘要】 风能作为绿色无污染的可再生能源具有良好的发展前景,目前世界各国都日益重视风能的开发和利用。随着风电产业的迅速发展,直驱型风力发电系统以其诸多优点引起了广泛关注,成为当前研究热点之一,而全功率变流器控制技术是直驱型风力发电系统的核心技术。本文以双PWM变换器为研究对象,围绕永磁直驱型风力发电系统全功率变流技术展开研究。首先对永磁直驱同步发电机(PMSG)进行了探讨,包括变速恒频技术的特点、PMSG风力发电系统变换器的拓扑结构,并以基于双PWM变换器拓扑结构的PMSG风力发电系统的变流技术作为本论文研究的核心。其次基于双PWM变换器的永磁直驱同步风力发电系统的工作原理,分析了永磁直驱同步电机系统的数学模型,包括风力机模型、轴系数学模型、全功率变流器的数学模型。然后针对永磁直驱同步电机的双PWM变换器,基于矢量控制技术分析研究了相应的控制策略,重点分析了零d轴电流矢量控制策略和电压定向矢量控制策略,并通过仿真验证了这两种控制策略的有效性。最后,对在电网电压发生跌落故障时直驱型风力发电机网侧变流器的动态运行情况进行了详细的分析,并运用仿真模拟电网电压跌落故障时直驱风力发电统的运行状态,以及分析如果不采取措施可能对风力发电系统所造成的损害。在介绍低电压穿越概念的基础上,分析了一种基于耗能Crowbar加卸荷电路的低电压保护方案,在此基础上设计了一种加卸荷电路的网侧控制策略,通过仿真结果验证了这种方法有效可靠,能够帮助永磁直驱风电机组在电网发生电压跌落故障时实现低电压穿越。更多还原

【Abstract】 As a kind of pollution-free and green renewable energy, wind power has a very promising future, many countries attach great importance to the development and use of wind energy, As wind power industry develops rapidly, direct-driven wind power system attracted wide attention for many advantages, it is now one of the current research focus, while the full-scale power converter control technology is the core technology of direct-driven wind power generation system.This dissertation researches on full-scale grid-connected power conversion technology for direct-driven wind generation system based on back-to-back PWM converter.Firstly, the direct-driven wind turbine with permanent magnet synchronous generator(PMSG) is discussed, which includes the feature of variable speed constant frequency, the topological structure of D-PMSG wind turbine systems converter, base on the topological structure of back-to-back PWM convertor. The power conversion technology for D-PMSG base on the topological structure of back-to-back PWM convertor is built as the core of this dissertation;Secondly, the mathematical model of D-PMSG wind turbine systems, which includes the model of wind turbine, the mathematical model of shaft-line, the model of full-scale power convertor is analyzed through the research on the principle of D-PMSG wind turbine systems based on back-to-back PWM convertor;Thirdly, aims at the back-to-back PWM convertor of D-PMSG and reposes on the technique of vector control, mainly analyzes on the control principle of the zero d-axis current vector in the motor-side and the voltage-oriented vector control principle for the grid-side. The validity of these two control methods is confirmed through the Matlab/Simulink simulation;Finally, the operational aspect of the converter of directly-driven wind generation system when grid voltage dips is analyzed in detail, then the running state of the D-PMSG when grid voltage dips is simulated by Matlab/Simulink, describes the possible damages of the system if we don’t take any effective measures. After introducing the concept of LVRT, a method of adding a damping load to protect the system based on power dissipative crowbar is analyzed, and the related module of control methods is designed, this method is confirmed effective and reliable through the Matlab/Simulink simulation, it can help the D-PMSG to ride through the low voltage during the breakdown time.更多还原