【作者】 王斌；

【导师】 肖建；

【作者基本信息】 西南交通大学 ， 电力电子与电力传动， 2004， 硕士

【摘要】 近20年来，异步电动机直接转矩控制以其简洁明了的系统结构，优良的静、动态性能，得到了极大的发展。它直接在定子坐标系下计算和控制交流电动机的转矩，采用定子磁场定向控制，直接对逆变器的开关状态进行最佳控制。 以TI公司生产的电机专用数字信号处理器TMS320F240为核心，可方便的实现直接转矩控制系统的全数字化。本文对异步电机直接转矩控制变频调速方法进行了研究，采用DSP汇编语言完成了有速度传感器的直接转矩控制系统的软件编写，实现了定子相电流采样、相电压的计算、定子磁链的观测、开关信号输出等功能。完成了近似圆形磁链直接转矩控制闭环系统的构建，从而证明此方法的可行性。在文中分析了转矩滞环和磁链滞环参数的变化对控制系统性能的影响，并且采用磁链弱反馈的方法对定子磁链的观测进行了改进，同时采用积分分离式PI调节算法对传统的PI调节器进行了改进。 通过理论分析和对控制系统的设计，在DSP电机控制教学实验及系统开发平台上对圆形磁链控制算法进行了初步的闭环实验，完成了电机在参考转速恒定条件下变负载实验和恒定负载条件下的变速实验，并对实验结果进行了对比分析，结果验证了系统设计方案的可行性。 转矩脉动和磁链脉动是影响传统直接转矩控制性能的主要因素，因此本文通过实验所得波形对其产生的原因进行了分析，并提出了对传统直接转矩控制进行改进的一些设想。更多还原

【Abstract】 During the recent 20 years, Direct Torque Control (DTC) for induction motor has been developed greatly because of its simple system scheme and excellent dynamic and static performances. In this scheme, the torque of motor is calculated and controlled in the stator reference frame. By using stator field orientation, the optimum switching mode is achieved to control the inverter.The digital DTC system is implemented easily using TMS320F240, which is a fixed-point DSP and developed specially for motor&motion control by Texas Instruments Inc. The DTC scheme is studied in the paper, and the software of control system with speed sensor is complied in DSP assembly language. This software has realized functions of the sampling of stator phase current, the calculating of the phase voltage, the observing of stator flux and the output of switching signal etc. In this paper, performances have been analyzed when the parameter of torque hysteretic comparator or the hysteretic band of stator flux is changed. The system of circle flux control is completed and the feasibility of the scheme is proved. In addition, the traditional PI regulator and the observer of stator flux are improved in this paper.According to the analysis of the theory of DTC scheme and the design of the control software, some primary experiments of the close-loop circle flux control system have been done using the DSP test-bed for experimentation and development of motor control. Experiments of motor with variable load or at a variable given speed are completed in this paper. These results are compared and analyzed. The feasibility of the scheme is showed through these results.Fluctuations of torque and stator flux are the main factors, which affect the performance of the traditional DTC system. So reasons of fluctuations of torque and stator flux are analyzed in this paper and some suggestions are raised.更多还原