【作者】 王文超；

【导师】 陈昊；

【作者基本信息】 中国矿业大学 ， 电气工程， 2019， 硕士

【摘要】 开关磁阻发电机具有结构简单坚固、制造成本低、容错性能好等优点,在风力发电领域具有较大优势,应用前景广阔。然而常用的不对称半桥功率变换器通用性较差,制造标准不统一,成本高,限制了开关磁阻发电机的应用。三相全桥变换器由于在交流电机中的广泛应用,已成为一种成熟通用的标准驱动模块,制造成本低,但在开关磁阻发电机系统中的研究和应用较少。因此,本文以三相全桥功率变换器开关磁阻发电机控制系统为研究对象,对开关磁阻发电机双极性控制的基本原理,励磁方式,开通角、关断角、转速等控制参数的变化对系统输出功率和发电效率的影响进行探讨。首先介绍了课题研究背景,总结了开关磁阻发电机在风力发电应用中的优势和不足,阐述了开关磁阻发电机在电机建模、不对称半桥和三相全桥功率变换器等方面的研究现状。然后,对不对称半桥、H桥和三相全桥三种功率变换器的结构特性进行了分析和对比,分析了三相全桥功率变换器工作过程中的励磁、续流、发电三个阶段,推导了三相全桥功率变换器工作过程中的电压方程和转矩方程,分析了开关磁阻发电机运行过程中的能量转换关系。最后,介绍了三相全桥功率变换器三相三拍和三相六拍两种励磁方式,给出了两种励磁方式下每个励磁区间的电流路径、功率开关状态和相电流方向,对比了两种励磁方式的运行特性和优缺点,分析了三相全桥功率变换器工作时超前和滞后两种绕组串联方式。利用有限元软件FLUX搭建了开关磁阻发电机二维有限元模型,通过瞬态求解器进行了三相全桥开关磁阻发电机控制系统在不同控制参数下的仿真实验,分析了开通角、关断角和转速等控制参数的变化对系统输出功率和发电效率的影响。利用RT-LAB搭建了三相全桥开关磁阻发电机双极性控制系统实验平台,进行了不同控制参数下输出功率与发电效率的对比实验,并将实验结果与仿真结果进行对比。仿真和实验表明:基于三相全桥功率变换器的开关磁阻发电机系统能够良好平稳的运行,效率较高,在转速较高时可替代不对称半桥功率变换器。更多还原

【Abstract】 Because of simple and sturdy structure,low manufacturing cost and good fault tolerance performance,switched reluctance generator has great advantages in wind power generation,showing broad application prospects.However,the frequentlyapplied asymmetric half-bridge power converters have poor versatility,uniform manufacturing standards,and high cost,which limits the application of switched reluctance generators.Due to wide application in AC motors and low manufacturing cost,three-phase full-bridge converters have become a mature and versatile standard drive module.However,applications and researches of three-phase full-bridge converters have limited investigation in switched reluctance generator systems.Therefore,this paper takes the control system of three-phase full-bridge power converter switched reluctance generator as research object,and investigates in the basic principle of bipolar control,excitation mode,the influence of changing control parameters,i.e.turn-on angle and turn-off angle and speed,on system output power and efficiency.Firstly,the research background is introduced,the advantages and disadvantages of switched reluctance generator in wind power generation are summarized.The research status of switched reluctance generator modeling,asymmetric half-bridge power converter and three-phase full-bridge power converter is described.Then,the structural characteristics of three power converters,i.e.asymmetric half-bridge,Hbridge and three-phase full-bridge,are analyzed and compared.The three stages of excitation,freewheeling and power generation in the operation of three-phase fullbridge power converter are analyzed.The voltage equation and torque equation under the operation of three-phase full-bridge power converter are deduced under bipolar operation,and the energy transformation in process of switched reluctance generator is analyzed.Finally,two excitation modes,i.e.three-phase three-beat and three-phase sixbeat,are introduced.The current circuit,power switching state and phase current direction of each excitation region are given under two excitation modes.The operation characteristics,advantages and disadvantages of two excitation modes are compared.The advanced winding series modes and the lagged winding series modes are analyzed.A 2-D finite element model of switched reluctance generator is built through the FLUX software.The current waveform of the bipolar control of three-phase full-bridge switched reluctance generator system is simulated by FLUX transient solver under different control parameters.The influence of the diffierent control parameters on the output power and efficiency is analyzed.An experimental platform of bipolar control of three-phase full-bridge switched reluctance generator system is built based on RTLAB.The experimental data of power efficiency and output power under different control parameters is obtained,and the experimental data is compared with the simulation data.The simulation and experiment results show that the switched reluctance generator system can keep smooth operation drived by three-phase fullbridge power converter with relatively high efficiently,which means that three-phase full-bridge can take the place of asymmetric half-bridge power converter under high speed.更多还原