永磁同步电机转矩脉动抑制方法的研究

发布时间：2018-06-09 03:25

本文选题：永磁同步电机 + 转矩调节器　；参考：《扬州大学》2017年硕士论文

【摘要】：永磁同步电机比异步电机具有效率高、体积小、损耗低、结构简单、重量轻等优点。近年来随着电机控制技术、电力电子技术以及稀土永磁材料的发展,永磁同步电机已经在国防、家用电器、制造业、工业等领域得到了广泛的应用。目前永磁同步电机的控制方法主要有直接转矩控制和矢量控制,矢量控制方法通过改变电机的电枢电流来控制电机的转矩,需要创建受控对象的复杂数学模型,所以该控制方法实现起来较复杂,而直接转矩控制方法则直接在定子坐标系中计算和控制电机转矩,克服了矢量控制方法的复杂性。但是,在直接转矩控制的转矩调节器中由于采用正反矢量来增加和减少电机转矩,易导致电机在稳态运行时电机转矩和电流的脉动过大,使电机控制系统的运行性能达不到最优化,电机运行质量下降,因此需要在电机控制过程中对转矩脉动进行有效的抑制。为此本论文针对永磁同步电机的转矩脉动问题,进行了转矩脉动抑制方法的研究。本文分别利用零矢量控制法和反电动势形状函数控制法来抑制转矩脉动。零矢量控制法主要通过建立抑制转矩脉动的数学模型,将电机转矩表达式进行离散化,推导出了正矢量、反矢量和零矢量三者之间的转矩变化关系,根据电机的转矩给定值和实际转矩值之间的误差大小来判断转矩控制信号,进而选择性的调理转矩。反电动势形状函数控制法主要通过在两相导通控制的转矩观测器中,将传统的转子磁链控制改成反电动势控制,建立反电动势形状函数抑制转矩脉动的数学模型,将定子三相相反电动势经过标幺化处理后获得的三相形状函数与永磁同步电机的梯形波反电动势幅值进行乘积,再将乘积结果代入转矩方程中,获取电机转矩。最后,运用仿真软件的Simulink建立了零矢量抑制转矩脉动仿真模型和反电动势形状函数抑制转矩脉动仿真模型,从其仿真结果分析,零矢量和反电动势形状函数的引入确实有效地抑制了转矩脉动。为了验证仿真分析的正确性,对仿真结果进行了实验验证,实验结果和仿真中得到的规律基本一致,实验和仿真结果验证了上述两种脉动抑制方法的正确性。
[Abstract]:PMSM has the advantages of high efficiency, small volume, low loss, simple structure and light weight. In recent years, with the development of motor control technology, power electronics technology and rare earth permanent magnet materials, PMSM has been widely used in national defense, household appliances, manufacturing, industry and other fields. At present, the control methods of permanent magnet synchronous motor mainly include direct torque control and vector control. The vector control method controls the motor torque by changing the armature current of the motor, so it is necessary to create a complex mathematical model of the controlled object. Therefore, the control method is more complex to realize, while the direct torque control method directly calculates and controls the motor torque in the stator coordinate system, which overcomes the complexity of the vector control method. However, due to the use of positive and negative vectors to increase and reduce the torque of the motor in direct torque control, it is easy to cause excessive ripple of the torque and current of the motor in steady state operation. The performance of motor control system can not be optimized and the running quality of motor is decreased, so it is necessary to restrain torque ripple effectively in the process of motor control. In this paper, the torque ripple suppression method of permanent magnet synchronous motor (PMSM) is studied. In this paper, zero vector control and back EMF shape function control are used to suppress torque ripple, respectively. By establishing a mathematical model to suppress torque ripple, the expression of motor torque is discretized, and the relationship among positive vector, inverse vector and zero vector is deduced. The torque control signal is judged according to the error between the given torque value and the actual torque value, and then the torque is adjusted selectively. The shape function control method of backEMF is mainly based on changing the traditional rotor flux control into backEMF control in the torque observer of two-phase conduction control, and establishes a mathematical model of the shape function of backEMF to suppress torque ripple. The three-phase shape function obtained by the stator three-phase back-EMF is multiplied with the amplitude of the trapezoidal backEMF of the permanent magnet synchronous motor (PMSM), and the result of the product is substituted into the torque equation to obtain the torque of the motor. Finally, the simulation model of zero vector suppression torque ripple and the simulation model of back EMF shape function are established by Simulink, and the simulation results are analyzed. The introduction of zero vector and back EMF shape function can effectively restrain torque ripple. In order to verify the correctness of the simulation analysis, the simulation results are verified by experiments. The experimental results are basically consistent with the laws obtained in the simulation. The experimental and simulation results verify the correctness of the two methods mentioned above.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TM341

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