永磁同步电机相电流重构技术研究

发布时间：2018-02-28 05:03

本文关键词： 永磁同步电机相电流重构无位置传感器滑模观测器模型参考自适应　出处：《哈尔滨工业大学》2014年硕士论文　论文类型：学位论文

【摘要】：永磁同步电机以其高功率密度、高可靠性、高精度等众多优点在工业伺服领域得到了广泛应用。现代永磁同步电机多采用闭环矢量控制驱动系统，需要实时检测转子位置和相绕组电流值，而无论是位置传感器还是电流传感器价格都不菲，从而阻碍了永磁同步电机伺服系统成本的下降，限制了其应用范围的拓展。本文从通过减少电流传感器的数量以降低成本的角度出发，详尽阐述了几种基于单电流传感器的相电流重构方法。首先，在采用SVPWM技术的矢量控制基础上，介绍了基于母线电流传感器进行相电流重构的基本原理，考虑到实际系统中非理想因素的影响，划分了电流重构盲区。通过脉冲移位法解决了重构盲区问题，并理论推导证明了该方法不影响实际输出的电压矢量。经仿真和实验表明脉冲移位法能够基本解决重构盲区的问题，但会使电流中高频谐波的含量稍有增加。同时针对过调制运行情况下的电流重构也提出了解决方案。其次，为实现在整个电压矢量区域内都能准确地完成相电流的重构，引入了矢量脉冲插入法。这种方法可以不受电压矢量的制约，在任意区域实现电流的重构。并根据实际需求，提出了基于单极性电流传感器的脉冲插入法，同时给出了低调制区域的简化方案。但测量脉冲的引入，会带来母线电压利用率的下降，电流谐波含量的上升，，驱动器开关损耗的急剧增加等弊端。再次，从改进传统SVPWM技术的角度出发，阐述了三态脉宽调制技术和混合脉宽调制技术，详尽介绍了两种调制技术的工作原理。并对不可测量的区域进行了理论分析和改进，同时进行了仿真和实验验证。实验结果表明采用三态脉宽调制技术能够有效扩大电流重构的有效区域，但由电流曲线可以看出其控制效果仍稍逊于传统SVPWM技术。接着，通过调整电流传感器的安装位置，使得在不改动传统矢量控制算法的前提下，在绝大部分矢量区域完成了电流重构。这种方式的好处在于丝毫不会降低原来系统的性能。但特定的安装方式使得其在IPM应用中受限，同时因缺乏母线电流传感器，过流保护功能的实现稍显复杂。跟着指出了电流重构存在的一些共性误差，并提出了相应解决方案。最后，为进一步降低系统成本，介绍了两种永磁同步电机无位置传感器技术,双观测器法和反步MRAS法。详细阐述了二者的工作原理，并将相电流重构技术和无位置传感器技术结合进行仿真。仿真结果表明：双观测器法的结果中存在小幅高频抖振，对系统稳定性不利；而反步MRAS法的估算准确性受电机参数影响较为敏感。总体来说，两种方法都能较为准确地完成对转子位置和速度的估算。
[Abstract]:Permanent magnet synchronous motor has been widely used in the field of industrial servo with many advantages such as high power density , high reliability and high precision . First , on the basis of vector control using the technology of space vector , the basic principle of phase current reconstruction based on bus current sensor is introduced , and the blind area of current reconstruction is divided according to the influence of non ideal factors in real system . The problem of reconstructed blind area is solved by pulse shift method . The simulation and experiment show that the method can solve the problem of reconstructing blind area basically , but it can increase the content of high frequency harmonic in current . Secondly , in order to realize the reconstruction of the phase current accurately in the whole voltage vector region , the vector pulse insertion method is introduced . The method can realize the reconstruction of the current in any region without the restriction of the voltage vector . According to the actual demand , a pulse insertion method based on a single - polarity current sensor is proposed , and the simplification scheme of the low modulation region is also given . However , the introduction of the measurement pulse can lead to the decrease of the utilization rate of the bus voltage , the rise of the current harmonic content , the abrupt increase of the switching loss of the driver , and the like . In this paper , the principle of three - state pulse width modulation ( PWM ) and hybrid pulse width modulation ( PWM ) is introduced in this paper . The working principle of two kinds of modulation techniques is introduced in detail . Then , by adjusting the installation position of the current sensor , the current reconstruction is completed in most of the vector areas without changing the traditional vector control algorithm . The advantage of this method is that the performance of the original system is not reduced . However , the specific installation mode makes it limited in the IPM application . At the same time , due to the lack of the bus current sensor , the realization of the over - current protection function is slightly more complicated . Then , some common errors in the current reconstruction are pointed out , and the corresponding solutions are proposed . Finally , in order to further reduce the system cost , two kinds of permanent magnet synchronous motor sensorless technique , double observer method and inverse MRAS method are introduced . The working principle of the two kinds of permanent magnet synchronous motors is described in detail , and the phase current reconstruction technique and the sensorless technique are combined . The simulation results show that there is small amplitude high frequency buffeting in the results of the double observer method and the system stability is bad ; and the estimation accuracy of the inverse MRAS method is more sensitive to the influence of the parameters of the motor . Generally , both methods can accurately estimate the rotor position and speed .

【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM341

【共引文献】