异步电机直接转矩控制及实验研究

发布时间：2018-01-08 20:17

本文关键词：异步电机直接转矩控制及实验研究　出处：《大连海事大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着交流调速技术的不断发展,直接转矩控制策略在工程实践中的地位越来越重要。以其简单的结构、快速的转矩响应、较好的动态和静态性能以及不依赖于电动机多种参数限制等优点,得到了广泛的认可。本文依据大量参考文献,对交流调速的发展史做了简要的介绍,详细分析了异步电机的数学模型和常用的坐标变换。介绍了直接转矩控制的基本原理,通过分析,传统直接转矩控制系统存在诸多需要改进的地方,例如转矩存在脉动、逆变器开关频率不恒定、定子磁链无法准确估算等。本文提出了空间矢量脉宽调制(SVPWM)结合新型磁链观测器的直接转矩控制方案,将该方案称之为改进的直接转矩控制策略。本文用PI调节器代替传统直接转矩控制系统中的滞环调节器,用新型的磁链观测器代替传统的纯积分观测器,建立了仿真模型,证明了新型磁链观测器观测精度明显提高。在MATLAB/Simulink工具中进行仿真研究,并对传统DTC系统仿真结果进行详细的分析,证明了直接转矩控制策略的可行性和正确性。通过对改进系统仿真结果的分析,证明了改进的直接转矩控制系统能够消除转矩脉动、精确估算定子磁链和解决逆变器开关频率不恒定的问题。本文以美国微芯科技公司推出的dsPIC33FJ128MC706A数字信号控制器作为核心控制芯片搭建硬件平台,并在MPLAB开发环境中进行软件程序调试。最后,得到了良好的实验结果。
[Abstract]:With the development of AC speed regulation technology, direct torque control strategy plays an increasingly important role in engineering practice, with its simple structure, rapid torque response. The advantages of better dynamic and static performance and independent of the motor parameters are widely recognized. Based on a large number of references, this paper gives a brief introduction to the history of AC speed regulation, analyzes in detail the mathematical model and coordinate transformation of asynchronous motor, and introduces the basic principle of direct torque control. Through analysis, there are many improvements in the traditional direct torque control system, such as torque ripple, inverter switching frequency is not constant. The stator flux can not be estimated accurately. In this paper, a direct torque control scheme based on space vector pulse width modulation (SVPWM) combined with a new flux observer is proposed. In this paper, Pi regulator is used to replace the hysteresis regulator in the traditional direct torque control system, and a new flux observer is used to replace the traditional pure integral observer. The simulation model is established, and it is proved that the observation accuracy of the new flux observer is improved obviously. The simulation research is carried out in MATLAB/Simulink tool. The simulation results of the traditional DTC system are analyzed in detail, which proves the feasibility and correctness of the direct torque control strategy. It is proved that the improved direct torque control system can eliminate torque ripple, estimate stator flux accurately and solve the problem of unsteady switching frequency of inverter. In this paper, the dsPIC33FJ128MC706A digital signal controller developed by the American Microcore Technology Company is used as the core control chip to build the hardware platform. The software program is debugged in MPLAB development environment. Finally, good experimental results are obtained.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM343

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