永磁同步电机伺服系统实用技术的研究
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摘要
随着微电子技术和电力电子器件的发展、电机加工工艺的提高以及现代控制理论的逐步成熟,高性能、智能化、低成本、高可靠性的永磁同步电机伺服系统将会越来越多地应用于军用、工业及日常生活的各个领域。本文围绕永磁同步电机伺服系统的实用技术展开,主要对交流伺服系统调试工具开发、死区补偿技术及转动惯量辨识技术进行了深入研究。
首先分析了永磁同步电动机数学模型,在此基础上阐述永磁同步电机矢量控制理论,同时确定了id = 0的矢量控制方案。硬件系统以Freescale公司高性能DSP芯片MC56F8346为控制核心,以芯微公司智能功率模块(IPM)IM234000为功率变换装置,进行永磁同步电机全数字伺服系统的软硬件设计。实验证明此硬件平台可以稳定、可靠地运行,满足进一步深入研究的需要。
然后本文详细论述基于模块化思想设计的一款通用交流伺服系统调试软件。该软件利用PC上位机与伺服驱动器进行串行通信完成应用现场调试任务。针对伺服系统参数实时调试、运行数据实时显示等特殊要求,从软件各重要部分的设计展开讨论。大量工程实践验证了此软件操作简便、运行可靠、功能实用,极大地提高了工程人员现场调试效率。
接着深入研究了对伺服系统低速性能产生较大影响的逆变器死区效应。分析了传统的死区补偿方法后,利用位置传感器判断相电流极性实施死区补偿。实验证明此方法克服了传统方法的诸多问题,有效减小了相电流谐波,降低了转矩脉动。
最后对离线转动惯量辨识技术进行研究。在介绍了目前常用的几种方法后,对基于自适应控制中系统辨识理论的两类方法进行了仿真研究。对朗道离散时间递推参数辨识方法与传统加减速方法进行了对比实验,证明了前者不仅应用场合广,且辨识精度和辨识效率都有很大的提高。
Depending on the development of the micro-electronics technology and power electrical elements, along with the advance of the motor manufacture and maturity of the modern control theory, PMSM servo system has been applied widely in numerous fields such as military field, industrial field and daily life for its prominent characteristics such as high-performance, high intellectualized, low cost, high reliability. This paper focuses on practical technique of PMSM servo system and probes deep into the development of AC servo adjusting tool, dead-time compensation and inertia identification.
First of all, the mathematical model on which the vector control theory of the PMSM is illustrated is expound, with i d=0vector control method established. Designing hardware and software of PMSM digital servo system is based on control-core, high-performance digital signal processor named MC56F8346 manufactured by Freescale company, and power converter, intellectualized IM234000. Experiment result proves that the stability and reliability of this experimental system can satisfy the further research.
Secondly, this paper describes the process of software development aiming at tuning general AC servo system relying on communication between servo driver and personal computer by serial port. To arrive at the unique functions such as real-time adjustment and real-time display, some crucial element of the software and reliability are illustrated in detail. Proven by many engineering applications, this tool possesses simple operation, reliable operation and practical function which can improve efficiency.
Additionally, this paper probes deep into the research of dead-time in inverter, which has considerable influence on performance of AC servo system, especially in low speed status. After anglicizing traditional method, dead-time implement function can be executed basing on judging the polarity of phase current by position sensor. Experiment proves that this method can eliminate the problems existed in traditional method, and effectively minimums harmonic of current and torque ripple.
Finally, this paper focuses on off-line inertia identification technique. With some kinds of methods applied universally introduced, computer simulation research is implemented on two of them relying on system identification theory of adaptive control. Compared with traditional method in the contrast experiment, Landau's method is more precise, more efficient and more widely applied.
首先分析了永磁同步电动机数学模型,在此基础上阐述永磁同步电机矢量控制理论,同时确定了id = 0的矢量控制方案。硬件系统以Freescale公司高性能DSP芯片MC56F8346为控制核心,以芯微公司智能功率模块(IPM)IM234000为功率变换装置,进行永磁同步电机全数字伺服系统的软硬件设计。实验证明此硬件平台可以稳定、可靠地运行,满足进一步深入研究的需要。
然后本文详细论述基于模块化思想设计的一款通用交流伺服系统调试软件。该软件利用PC上位机与伺服驱动器进行串行通信完成应用现场调试任务。针对伺服系统参数实时调试、运行数据实时显示等特殊要求,从软件各重要部分的设计展开讨论。大量工程实践验证了此软件操作简便、运行可靠、功能实用,极大地提高了工程人员现场调试效率。
接着深入研究了对伺服系统低速性能产生较大影响的逆变器死区效应。分析了传统的死区补偿方法后,利用位置传感器判断相电流极性实施死区补偿。实验证明此方法克服了传统方法的诸多问题,有效减小了相电流谐波,降低了转矩脉动。
最后对离线转动惯量辨识技术进行研究。在介绍了目前常用的几种方法后,对基于自适应控制中系统辨识理论的两类方法进行了仿真研究。对朗道离散时间递推参数辨识方法与传统加减速方法进行了对比实验,证明了前者不仅应用场合广,且辨识精度和辨识效率都有很大的提高。
Depending on the development of the micro-electronics technology and power electrical elements, along with the advance of the motor manufacture and maturity of the modern control theory, PMSM servo system has been applied widely in numerous fields such as military field, industrial field and daily life for its prominent characteristics such as high-performance, high intellectualized, low cost, high reliability. This paper focuses on practical technique of PMSM servo system and probes deep into the development of AC servo adjusting tool, dead-time compensation and inertia identification.
First of all, the mathematical model on which the vector control theory of the PMSM is illustrated is expound, with i d=0vector control method established. Designing hardware and software of PMSM digital servo system is based on control-core, high-performance digital signal processor named MC56F8346 manufactured by Freescale company, and power converter, intellectualized IM234000. Experiment result proves that the stability and reliability of this experimental system can satisfy the further research.
Secondly, this paper describes the process of software development aiming at tuning general AC servo system relying on communication between servo driver and personal computer by serial port. To arrive at the unique functions such as real-time adjustment and real-time display, some crucial element of the software and reliability are illustrated in detail. Proven by many engineering applications, this tool possesses simple operation, reliable operation and practical function which can improve efficiency.
Additionally, this paper probes deep into the research of dead-time in inverter, which has considerable influence on performance of AC servo system, especially in low speed status. After anglicizing traditional method, dead-time implement function can be executed basing on judging the polarity of phase current by position sensor. Experiment proves that this method can eliminate the problems existed in traditional method, and effectively minimums harmonic of current and torque ripple.
Finally, this paper focuses on off-line inertia identification technique. With some kinds of methods applied universally introduced, computer simulation research is implemented on two of them relying on system identification theory of adaptive control. Compared with traditional method in the contrast experiment, Landau's method is more precise, more efficient and more widely applied.
引文
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[3]吴东苏.数字化永磁同步电机伺服驱动器的研究,[硕士学位论文].武汉:华中科技大学,2002.
[4]张彦召.永磁同步电机交流伺服系统研究,[硕士学位论文].南京:南京航空航天大学,2008.
[5]王健.现代交流伺服系统技术和市场发展综述.伺服控制,2007,(2):16~21.
[6]舒志兵等.交流伺服运动控制系统.北京:清华大学出版社,2006.
[7]唐任远.稀土永磁电机发展综述.电气技术,2005,(4):1~6.
[8]彭瑞.永磁同步电机交流伺服系统的研究,[硕士学位论文].南京:南京航空航天大学,2007.
[9]纪洪明.基于DSP的交流伺服驱动系统的研究与开发,[硕士学位论文].哈尔滨:哈尔滨工业大学,2006.
[10]曲家骐,王季秩.伺服控制系统中的传感器.北京:机械工业出版社,1998.
[11]吴茂刚.矢量控制永磁同步电动机交流伺服系统的研究,[博士学位论文].杭州:浙江大学,2006.
[12]许大中.交流电机调速理论.杭州:浙江大学出版社,1997.
[13]胡崇岳.现代交流调速技术.北京:机械工业出版社,2000.
[14]伍兵芳.全数字永磁交流伺服驱动系统的研究,[硕士学位论文].武汉:华中科技大学,2002.
[15]陈吉红.发展我国伺服驱动产业的探讨.航空制造技术,2006,(8):46~49.
[16]陈吉红,李斌,朱志红.由汉诺威EMO 2005看数控系统的发展趋势及思考.世界制造技术与装备市场,2006,(1):96~104.
[17]唐任远.现代永磁电机理论与设计.北京:机械工业出版社,1997.
[18]杜娟.高性能全数字交流伺服驱动器研究,[硕士学位论文].武汉:华中科技大学,2002.
[19]冬雷.DSP原理及电机控制系统应用.北京:北京航空航天大学出版社,2007.
[20]郭庆鼎,王成元.交流伺服系统.北京:机械工业出版社,1994.
[21]舒志兵等.交流伺服运动控制系统.北京:清华大学出版社,2006.
[22]陈坚.交流电机数学模型及调速系统.北京:国防工业出版社,1989.
[23]许大中.交流电机调速理论.杭州:浙江大学出版社,1997.
[24]胡崇岳.现代交流调速技术.北京:机械工业出版社,2000.
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