【作者】 张倩倩；

【导师】 周西峰；

【作者基本信息】 南京邮电大学 ， 控制理论与控制工程， 2011， 硕士

【摘要】 城市轨道交通正处于快速发展时期,轨道交通牵引系统正向着轻质量、小体积、低成本和高可靠性方向发展。在轨道交通牵引传动系统中,通常采用单台逆变器驱动两台或四台交流牵引电动机,这时以往的单台感应电动机的控制策略就不能满足要求,就有必要研究多台感应电动机并联驱动的控制策略和控制系统。本文从三相感应电动机的动态数学模型出发,阐述了单台感应电动机的矢量控制原理,给出了按转子磁链定向的矢量控制系统模型。然后针对两台感应电动机参数和负载不一致的情形,在原有单台感应电动机直接磁场定向矢量控制模型的基础上,结合平均的思想,设计了一个双感应电动机并联驱动矢量控制系统,并针对空载和带载不平衡的情况进行了仿真分析。仿真结果表明:系统能够获得良好的稳态性能和动态性能。接着深入研究四台感应电动机并联驱动矢量控制原理,给出了四台感应电动机并联驱动的磁链模型和转矩模型的推导过程,设计了四台感应电动机并联驱动矢量控制系统。由于PI控制在交流调速系统中的局限性,为了使系统获得更好的性能,将模糊PID控制器应用于该系统的转速控制器,并对采用常规PI控制器和采用模糊PID控制器的系统进行了仿真。仿真结果表明,无论在启动或运行时负荷均衡与否,相比之下,基于模糊自适应PID控制器的系统更能平稳运行,且具有较好的动、静态性能,最后本文推导了多台感应电动机并联驱动的动态模型。本文方案的研究对轨道交通意义较大。更多还原

【Abstract】 With the rapid development of the railway traction system, the traction drive system of railway traction system tends to be light weight,small size, low cost and high reliability. In railway traction system, two to four induction motors operating in parallel are required to ensure the normal running. Thus the control strategies of single inverter single motor can’t meet the requirement. And it is necessary to study the control strategies and the system of multi-induction motor drive system.According to the dynamic model of induction motor and vector control theory on single induction motor, the vector control systems of two paralle1-connected induction motors is established which takes the different parameters and unbalanced loads of motor into account while combining the idea of the average.At the same the simulations are finished on the condition of the torque step change and the speed step change. The simulation results show that the system has good performance in dynamic state and stable state.According to the vector control theory of four paralled-connected induction motors, the derivation processes of the flux model and torque model of the four parallel-connected induction motor drive system are given. And the vector control systems of four parallel-connected induction motor are designed.Because of the limitations of PI control when applying to the ac speed regulating system,the paper makes full use of the advantages of fuzzy logical PID.Regardless of unbalanced loads at starting, unbalanced loads at running or balanced loads at running, The simulation results show that the system can run more smoothly and has a better dynamic and static performance when adopted the fuzzy logical PID.The study of scheme is of significance, especially in rail transport.更多还原