六相感应电机无速度传感器直接转矩控制系统研究

发布时间：2018-03-21 17:09

本文选题：六相感应电机　切入点：直接转矩控制　出处：《中国矿业大学》2017年硕士论文　论文类型：学位论文

【摘要】：与三相电机驱动系统相比,多相电机调速控制系统具有很多优点,如相同电压等级条件下输出功率大、转矩脉动低和动静态性能好等。多相系统还具有可靠性高的特点,能够在缺相条件下通过调整控制策略继续运行。因此,在战舰、航天等对可靠性要求非常高的大功率应用场合,多相系统的应用日趋广泛。六相电机驱动系统的控制策略中,最为常见的有两种:矢量控制和直接转矩控制。与矢量控制相比,直接转矩控制策略的优势在于,不需要将转子模型从旋转坐标系变换到静止坐标系下,而且由于转矩直接作为控制对象,所以反应更加迅速。多相电机的特点决定了其应用场合所处环境较为恶劣,但对可靠性要求反而非常高。而闭环控制中速度的反馈常使用速度传感器测量实时的电机转速,速度传感器属于精密设备,受环境影响较大,所以对无速度传感器多相电机调速系统的研究是有一定实用意义的。本文围绕六相电机无速度传感器的直接转矩控制系统展开研究。首先,利用空间矢量解耦变换对高度耦合的六相电机进行空间解耦,并建立用以控制的电机数学模型。其次,通过合成中间电压矢量解决了定子谐波电流含量较大的问题。将适用于三相系统的过调制算法推广到六相电机调速系统中。推广了合成中间电压矢量理论,用以解决电机控制系统中存在共模电磁干扰的问题。且对以上算法进行了仿真验证。再次,对六相电机直接转矩控制系统展开了研究,并在此基础上研究了无速度传感器运行。将人工神经网络控制理论运用在六相电机直接转矩控制的转速辨识中,利用神经网络的快速收敛性、精度高等优点,提高了六相电机转速辨识的性能。且对该算法进行了仿真验证。最后,在硬件实验平台上对以上理论、算法进行了实验验证,分别完成了使用速度传感器条件下和无速度传感器条件下的实验验证。实验结果证明了文中理论的正确性。
[Abstract]:Compared with the three-phase motor drive system, the multi-phase motor speed control system has many advantages, such as large output power under the same voltage level, low torque ripple and good dynamic and static performance. It can continue to run under the condition of lack of phase by adjusting the control strategy. Therefore, in high power applications such as warships, spaceflight and so on, the application of multiphase system is becoming more and more extensive. In the control strategy of six-phase motor drive system, There are two most common methods: vector control and direct torque control. Compared with vector control, the advantage of direct torque control strategy is that there is no need to transform rotor model from rotating coordinate system to static coordinate system. And because torque is directly the object of control, so the reaction is more rapid. The characteristics of multiphase motor determine the environment of its application is relatively bad, However, the speed feedback in closed-loop control often uses speed sensor to measure the real time motor speed. The speed sensor belongs to the precision equipment and is greatly affected by the environment. Therefore, the research on speed control system of speed sensorless multiphase motor is of certain practical significance. This paper focuses on the direct torque control system of six-phase motor without speed sensor. The space vector decoupling transformation is used to decouple the highly coupled six-phase motor, and the mathematical model of the motor for control is established. By synthesizing intermediate voltage vector, the problem of large stator harmonic current content is solved. The over-modulation algorithm suitable for three-phase system is extended to six-phase motor speed regulation system, and the synthetic intermediate voltage vector theory is generalized. It is used to solve the common mode electromagnetic interference problem in motor control system, and the simulation of the above algorithm is carried out. Thirdly, the direct torque control system of six-phase motor is studied. On this basis, the speed sensorless operation is studied. The artificial neural network control theory is applied to speed identification of six-phase motor direct torque control, and the advantages of fast convergence and high precision of neural network are used. The performance of speed identification of six-phase motor is improved, and the algorithm is verified by simulation. The experimental results under the condition of using speed sensor and without velocity sensor have been completed, and the experimental results have proved the correctness of the theory in this paper.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM346;TP273

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