无位置传感器永磁无刷直流电机控制策略的研究
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摘要
永磁无刷直流电机所具有的高转矩、高效率等优良性能,使其在现代工业中得到了广泛应用,但是位置传感器的存在给其带来了诸多弊端,同时转矩脉动问题也在一定程度上限制了其在高精度场合的应用。本文分析了几种常见的无位置传感器控制技术,重点研究了反电动势法,并分析研究了低转速运行时非换相转矩脉动及其抑制问题。最后本课题以TMS320F2812芯片为核心,研究了永磁无刷直流电机无位置传感器的控制系统。
论文分析了永磁无刷直流电机的工作控制原理,并建立了相关的数学模型,以此为基础研究了反电动势法和非换相转矩脉动抑制等控制策略。反电动势法中,详细分析了模拟中性点过零检测法。而对于非换相转矩脉动问题,分析了永磁无刷直流电机低转速时运行特性,可知此阶段的换相转矩脉动能够得到有效地抑制,提出了运用PWM_ON_PWM调制方式抑制非换相转矩脉动,从而提高低转速永磁无刷直流电机的转矩控制精度。然后在Matlab/Simulink仿真环境里搭建了仿真模型,用以研究验证所提出的控制策略,所得的仿真结果表明所设计的控制系统可以得到良好的性能,PWM_ON_PWM调制方式能够使得非换相转矩脉动得到有效抑制。
以仿真结果为基础,论文设计制作了主要包括功率驱动电路和转子位置信号检测电路两部分的控制系统硬件电路。功率驱动电路部分以驱动芯片IR21367为核心搭建而成,同时还有光耦隔离电路和过流过压保护电路；转子位置信号检测电路作为无位置传感器控制系统的重要部分,本文为其设计了模拟中性点过零检测法电路,达到检测反电动势过零点的目的。
在CCS3.1软件编译环境下用C语言完成控制系统软件的编程,由于采用了模块化编程思想,使其具有较好的扩展性和通用性,方便用户的编程设计。最后对整个控制系统进行充分调试,在确定了控制系统的可靠性和稳定性之后,得出了电机一系列的工作波形,并对转速数据进行处理,得出了电机转速曲线。通过结果分析可知,本文所设计的基于无位置传感器的控制系统,不但能够稳定运行,而且比有位置传感器的控制系统取得更好的控制效果。
Permanent magnet brushless DC motor(PM BLDCM) has been widely used in modern industry, because it has some excellent performance such as high torque^high efficiency and so on. However, the existence of position sensor brights many disadvantages to the motor and the torque ripple also limit its application in high precision to some extent. This paper analyzes the some common non-position sensorless control technologies, focuses on back EMF method, and analysis of the low speed running motor non commutation torque ripple suppression problem.
The paper introduces the control principle ofPM BLDCM and establishes mathematical model Based on the above results, the back-EMF method and PWM_ON_PWM pulse width modulation control strategy are presented. In the back EMF method, a detailed analysis of the simulation of neutral point zero-crossing detection method is introduced. For the commutation torque ripple, the paper analyzes operation characteristics of permanent magnet brushless DC motor at low speed, the commutation torque ripple of the stage can be effectively suppressed, the PWMONPWM modulation mode is given to inhibition non commutation torque ripple. The simulation model is established in Matlab/Simulink simulation environment to study control strategy. The simulation results show that the designed control system can get good performance and the PWM_ON_PWM pulse width modulation can reduce the non-commutation torque ripple effectively.
Based on the result of the simulation, the designed hardware circuit of the control system consists of the power drive circuit and the rotor position signal detecting circuit as the main two parts. With drive chip IR21367as the core structure, the power drive circuit is built. Meanwhile, the optocoupler isolation circuit and the over-current and over-voltage protection circuit are both included as the secondary parts. As an important part of the non-position sensor control system, the paper designs the virtual neutral point zero crossing detection circuit for the rotor position detection circuit, to reach the purpose in detecting the zero-cross ing.
The control system software programming is completed by C language in the CCS3.1software compile environment. The designed soft system has good versatility and scalability in the result of adopting modular programming ideas. In the end, the whole control system is debugged fully. After making sure the reliability and stability of the control system, a series of motor working waveforms are obtained, The motor speed curve is obtained by processing the speed data. The results of analysis indicate that the designed control system based on non-position sensor not only run stably, but also has a better control effect than the control system based on position sensor.
论文分析了永磁无刷直流电机的工作控制原理,并建立了相关的数学模型,以此为基础研究了反电动势法和非换相转矩脉动抑制等控制策略。反电动势法中,详细分析了模拟中性点过零检测法。而对于非换相转矩脉动问题,分析了永磁无刷直流电机低转速时运行特性,可知此阶段的换相转矩脉动能够得到有效地抑制,提出了运用PWM_ON_PWM调制方式抑制非换相转矩脉动,从而提高低转速永磁无刷直流电机的转矩控制精度。然后在Matlab/Simulink仿真环境里搭建了仿真模型,用以研究验证所提出的控制策略,所得的仿真结果表明所设计的控制系统可以得到良好的性能,PWM_ON_PWM调制方式能够使得非换相转矩脉动得到有效抑制。
以仿真结果为基础,论文设计制作了主要包括功率驱动电路和转子位置信号检测电路两部分的控制系统硬件电路。功率驱动电路部分以驱动芯片IR21367为核心搭建而成,同时还有光耦隔离电路和过流过压保护电路；转子位置信号检测电路作为无位置传感器控制系统的重要部分,本文为其设计了模拟中性点过零检测法电路,达到检测反电动势过零点的目的。
在CCS3.1软件编译环境下用C语言完成控制系统软件的编程,由于采用了模块化编程思想,使其具有较好的扩展性和通用性,方便用户的编程设计。最后对整个控制系统进行充分调试,在确定了控制系统的可靠性和稳定性之后,得出了电机一系列的工作波形,并对转速数据进行处理,得出了电机转速曲线。通过结果分析可知,本文所设计的基于无位置传感器的控制系统,不但能够稳定运行,而且比有位置传感器的控制系统取得更好的控制效果。
Permanent magnet brushless DC motor(PM BLDCM) has been widely used in modern industry, because it has some excellent performance such as high torque^high efficiency and so on. However, the existence of position sensor brights many disadvantages to the motor and the torque ripple also limit its application in high precision to some extent. This paper analyzes the some common non-position sensorless control technologies, focuses on back EMF method, and analysis of the low speed running motor non commutation torque ripple suppression problem.
The paper introduces the control principle ofPM BLDCM and establishes mathematical model Based on the above results, the back-EMF method and PWM_ON_PWM pulse width modulation control strategy are presented. In the back EMF method, a detailed analysis of the simulation of neutral point zero-crossing detection method is introduced. For the commutation torque ripple, the paper analyzes operation characteristics of permanent magnet brushless DC motor at low speed, the commutation torque ripple of the stage can be effectively suppressed, the PWMONPWM modulation mode is given to inhibition non commutation torque ripple. The simulation model is established in Matlab/Simulink simulation environment to study control strategy. The simulation results show that the designed control system can get good performance and the PWM_ON_PWM pulse width modulation can reduce the non-commutation torque ripple effectively.
Based on the result of the simulation, the designed hardware circuit of the control system consists of the power drive circuit and the rotor position signal detecting circuit as the main two parts. With drive chip IR21367as the core structure, the power drive circuit is built. Meanwhile, the optocoupler isolation circuit and the over-current and over-voltage protection circuit are both included as the secondary parts. As an important part of the non-position sensor control system, the paper designs the virtual neutral point zero crossing detection circuit for the rotor position detection circuit, to reach the purpose in detecting the zero-cross ing.
The control system software programming is completed by C language in the CCS3.1software compile environment. The designed soft system has good versatility and scalability in the result of adopting modular programming ideas. In the end, the whole control system is debugged fully. After making sure the reliability and stability of the control system, a series of motor working waveforms are obtained, The motor speed curve is obtained by processing the speed data. The results of analysis indicate that the designed control system based on non-position sensor not only run stably, but also has a better control effect than the control system based on position sensor.
引文
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[2]刘刚,王志强,房建成.永磁无刷直流电机控制技术与应用[M].北京：机械出版社,2009.
[3]苏奎峰,蔡昭权,吕强,张永谦.[MS320X281x系列DSP原理及C程序开发[M].北京：北京航空航天大学出版社,2008.
[4]兰吉昌.TMS320F2812 DSP应用实例精讲[M].北京：化学工业出版社,2009.
[5]张卫宁.[MS320C28x系列DSP的CPU与外设[M].北京：清华大学出版社,2004.
[6]任润柏,周荔丹,姚钢.TMS320F28x源码解读[M].北京：电子工业出版社,2010.
[7]王兆安,黄俊.电力电子技术[M].北京：机械工业出版社,2000.
[8]康华光.电子技术基础模拟部分(第4版)[M].北京：高等教育出版社,2005.
[10]李颖.Sixnuliak动态系统建模与仿真(第2版)[M].西安：西安电子科技大学出版社,2009.
[11]杨明,徐殿国,贵献国.控制系统Anti-Windup设计综述[J].电机与控制学报,2006,10(6)：622-631.
[12]张相军,陈伯时.无刷直流电机控制系统中PWM调制方式对换相转矩脉动的影响[J].电机与控制学报,2003,7(2)：87-91.
[13]廖晖,廖政伟,吕征宇.基于PWM_ON_PWM改进型无刷直流电机的控制[J].电力电子技术,2011,11(45)：118-120.
[14]堵杰,孙承波,陈国呈.无刷直流电机换相过程中续流对电压和电流的影响[J].电工技术杂志,2002,5(3)：5-8.
[15]朱高剑,关振宏,张士奎.基于MATLAB的无刷直流电机控制系统建模与仿真[J].技术交流,2012,4(14)：37-41.
[16]韦鲲,胡长生,张仲超.一种新的消除无刷直流电机非导通相续流的PWM调制方式[J].中国电机工程学报,2005,25(7)：104-108.
[17]杨影,俞志轩,阮毅.基于反电动势的无刷直流电机无位置传感器控制技术综述[J].微电机,2011,2(44)：84-88.
[18]董少波,程小华.无刷直流电机转矩脉动及其抑制方法综述[J].微电机,2010,8(43)：83-86.
[19]王京锋,马瑞卿,孔纯祥.无刷直流电机换相转矩波动的分析研究[J].微电机,2006,6(39)：52-55.
[20]吴鹏坤,关振宏.IR21367在无刷直流电机控制中的应用[J].新特器件应用,2011, 1(13)：19-22.
[21]吴红星,叶宇骄,倪天,郭庆波.无刷直流电机转子位置检测技术综述[J].微电机,2011,8(44)：75-80.
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