【作者】 谭健；

【导师】 黄守道；

【作者基本信息】 湖南大学 ， 电气工程， 2008， 硕士

【摘要】 随着环境污染的日益严重和地球能源的日益紧缺,风能作为可再生绿色能源越来越被人们重视,风力发电技术也成为各国学者竞相研究的热点。而变速恒频双馈风力发电技术以其成本低、效率高等特点成为当今风力发电技术中的主流。本文首先介绍了风力发电技术的发展现状,通过对风力机机械转矩特性和双馈电机的研究,得出变速恒频风电机组的转矩——转速特性。在分析双馈感应发电机动态数学模型及其定子磁链定向矢量控制的基础上,构建了其有功和无功功率解耦控制的双闭环控制方案。利用MATLAB/SIMULINK平台进行了仿真研究,并验证了该控制方案的正确性,对实际系统的软硬件设计与调试具有一定的指导意义。然后,对作为双馈发电机励磁电源的双PWM变换器的拓扑结构及基本原理进行了深入研究,重点分析了三相PWM变换器在同步d-q坐标系中的数学模型。研究了带电流耦合、电网电压前馈补偿的控制策略,并通过仿真验证了双PWM变频器具有输入输出特性好、谐波少、能量可双向流动等特点。并将变速恒频双馈风力发电运行研究拓展到了电网故障条件下的运行控制。建立了计及电网电压故障的变速恒频双馈风力发电系统完整仿真模型。接着利用Simulink中的“Target for TI C2000”工具箱和TI公司的CCS集成开发环境,以网侧变换器为例,详细介绍了DSP代码的自动生成。最后,在仿真基础上设计了一套基于DSP的双馈风电模拟系统,系统采用一台5.5kW的绕线式异步电机做发电机,使用双DSP分别控制网侧和转子侧变换器,论文详细介绍了电压电流信号检测电路、通讯接口电路、正交编码脉冲电路和保护电路的设计,并给出了控制程序的主要流程。综上所述,本文研究成果为变速恒频双馈风电机组的控制系统的设计提供了理论依据,仿真结果验证了本文理论研究的正确性。更多还原

【Abstract】 With the pressing situation of fossil fuel exhaustion and environmental pollution, clean and renewable energy resources such as the wind energy are gaining more and more attention. Doubly-fed induction generator (DFIG) is an attractive and booming approach that provides the ability of variable speed constant frequency wind power generation with low cost and high efficiency.Firstly, the current development situation about the world wind power and wind power generation technology has been introduced. According to the mechanical torque characteristic of wind turbine and rotation speed-torque characteristic of doubly-fed machine, mechanical torque characteristic of VSCF wind turbine is obtained. Based on the analysis of the dynamic mathematical model of DFIG and its stator-flux-oriented vector control, a dual-closed-loop control scheme is developed and realizes decoupled control of the active and reactive power. Simulation study is carried out on the platform of MATLAB/SIMULINK and validates the proposed strategy, which will guide designing and debugging the practical software and hardware systems.Secondly, through the analysis of the work principle and topology frame of three phases voltage resource PWM converter, the mathematical model of the three-phase PWM converter in d-q synchronous reference frames is thoroughly investigate. The study of the control strategy shows that three-phase PWM converters are advantageous in high power factor, small input-line current harmonic distortion and bi-directional power flow. The full simulation model of the VSCF wind energy generation system with DFIG and back-to-back PWM converter is established, in which the grid voltage fault condition has been considered. The simulation model can be used to investigate the ride-through ability under grid faults, the new control scheme and other exploring research.Then the automatic generation of the DSP code with the application of the toolbox of Target for TI C2000 and the IDE of TI Corporation’s CCS.At last, simulating system of variable speed constant frequency wind generating is designed based on DSP and simulating. It is composed of a 5.5kW DFIG and grid-side and rotor-side converter which controlled by dual DSP controllers. The design of signal processing circuit, communications interface circuit, quadrature encoder pulse circuit and protection circuit has been introduce in detail. In summary, study results of this paper provide theoretical evidence for the design of the control system of variable-speed constant-frequency wind power conversion using doubly fed generator. The simulation results testify the validity of the theory and the control strategy proposed by this thesis.更多还原