直流电动机双闭环调速系统的研究外文翻译

1、中国地质大学长城学院本科毕业设计外文资料翻译 系 别信息工程系学生姓名专 业电气工程及其自动化学 号043111312015 年 3 月1 日外文资料翻译译文直流电动机双闭环调速系统的研究1概述直流电动机具有良好的起、制动性能，宜于在大范围内实现平滑调速，并且直流调速系统在理论和实践上都比较成熟，是研究其它调速系统的基础。而用MATLAB软件对直流调速系统进行虚拟环境下的仿真研究，不仅使用方便，也大大降低了研究成本。本文叙述了直流电动机的基本原理和调速原理，介绍了直流电动机开环和双闭环调速系统的组成及静、动态特性，并且根据直流电动机的基本方程建设立了调速系统的数学模型，给出了动态结构框图，用工

2、程设计方法设计了直流电动机双闭环调速系统。最后，用MATLAB仿真软件搭建了仿真模型，对调速系统进行了仿真研究。 通过对直流电动机双闭环调速系统动态特性的研究与仿真，可以清楚地看到，直流电动机双闭环调速系统具有较好的动态性能，可以在给定调速范围内，实现无静差平滑调速，这为直流电动机调速系统的硬件实验提供了理论依据。2双闭环直流调节系统的研究背景直流调速是现代电力拖动自动控制系统中发展较早的技术。在20世纪60年代，随着晶闸管的出现，现代电力电子和控制理论、计算机的结合促进了电力传动控制技术研究和应用的繁荣。晶闸管-直流电动机调速系统为现代工业提供了高效、高性能的动力。尽管目前交流调速的迅速发展

3、，交流调速技术越趋成熟，以及交流电动机的经济性和易维护性，使交流调速广泛受到用户的欢迎。但是直流电动机调速系统以其优良的调速性能仍有广阔的市场，并且建立在反馈控制理论基础上的直流调速原理也是交流调速控制的基础。现在的直流和交流调速装置都是数字化的，使用的芯片和软件各有特点，但基本控制原理有其共性。对于那些在实际调试过程中存在很大风险或实验费用昂贵的系统，一般不允许对设计好的系统直接进行实验。然而没有经过实验研究是不能将设计好的系统直接放到生产实际中去的。因此就必须对其进行模拟实验研究。当然有些情况下可以构造一套物理装置进行实验，但这种方法十分费时而且费用又高，而且在有的情况下物理模拟几乎是不可

4、能的。近年来随着计算机的迅速发展，采用计算机对控制系统进行数学仿真的方法已被人们采纳。 但是长期以来，仿真领域的研究重点是仿真模型的建立这一环节上，即在系统模型建立以后要设计一种算法。以使系统模型等为计算机所接受，然后再编制成计算机程序，并在计算机上运行。因此产生了各种仿真算法和仿真软件。由于对模型建立和仿真实验研究较少，因此建模通常需要很长时间，同时仿真结果的分析也必须依赖有关专家，而对决策者缺乏直接的指导，这样就大大阻碍了仿真技术的推广应用。MATLAB提供动态系统仿真工具Simulink，则是众多仿真软件中最强大、最优秀、最容易使用的一种。它有效的解决了以上仿真技术中的问题。在Simul

5、ink中，对系统进行建模将变的非常简单，而且仿真过程是交互的，因此可以很随意的改变仿真参数，并且立即可以得到修改后的结果。另外，使用MATLAB中的各种分析工具，还可以对仿真结果进行分析和可视化。Simulink可以超越理想的线性模型去探索更为现实的非线性问题的模型，如现实世界中的摩擦、空气阻力、齿轮啮合等自然现象；它可以仿真到宏观的星体，至微观的分子原子，它可以建模和仿真的对象的类型广泛，可以是机械的、电子的等现实存在的实体，也可以是理想的系统，可仿真动态系统的复杂性可大可小，可以是连续的、离散的或混合型的。Simulink会使你的计算机成为一个实验室，用它可对各种现实中存在的、不存在的、甚

6、至是相反的系统进行建模与仿真。自70年代以来，国内外在电气传动领域内，大量地采用了“晶闸管直流电动机调速”技术(简称VM调速系统)。尽管当今功率半导体变流技术已有了突飞猛进的发展，但在工业生产中VM系统的应用量还是占有相当的比重 。在工程设计与理论学习过程中，会接触到大量关于调速控制系统的分析、综合与设计问题。传统的研究方法主要有解析法，实验法与仿真实验，其中前两种方法在具有各自优点的同时也存在着不同的局限性。随着生产技术的发展，对电气传动在启制动、正反转以及调速精度、调速范围、静态特性、动态响应等方面提出了更高要求，这就要求大量使用调速系统。由于直流电机的调速性能和转矩控制性能好，从20世纪

7、30年代起，就开始使用直流调速系统。它的发展过程是这样的：由最早的旋转变流机组控制发展为放大机、磁放大器控制；再进一步，用静止的晶闸管变流装置和模拟控制器实现直流调速；再后来，用可控整流和大功率晶体管组成的PWM控制电路实现数字化的直流调速，使系统快速性、可控性、经济性不断提高。调速性能的不断提高，使直流调速系统的应用非常广泛。在工业生产中,需要高性能速度控制的电力拖动场合,直流调速系统,特别是双闭环直流调速系统发挥着极为重要的作用。转速、电流双闭环调速系统是20世纪60年代在国外出现的一种新型调速系统。70年代以来, 在我国的冶金、机械、制造以及印染工业等领域得到日益广泛的应用。双闭环调速系

8、统是由单闭环自动调速系统发展而来的。它通过转速和电流两个调节器分别引入转速负反馈和电流负反馈，并构成双闭环系统。从而有效的改善电机性能。 本设计主要采用三相全控桥式整流电路对直流电机供电，并通过工程设计法对转速调节器和电流调节器相关参数进行计算以达到对转速电流双闭环支流调速系统的整体实现。3系统工作原理该系统主要由主开关，电机励磁电路，晶闸管调速控制电路（包括 转速表电路），整流滤波电路，平波电抗器放电电路，能耗制动电路，整个系统采用闭环PI调节器控制的实现。当主开关闭合，这单相交流获得小的脉冲持续电流通过晶闸管调速控制电路的控制，和整流桥，为电机的滤波及平波电抗器，并在同一时间，通过整流励磁

9、电路，交流使电机获得激励去开始工作。在调节触发电路的速度设置电位器RP1由PIC16F877减少时，AN1输入电压下降使输出控制的角度，和晶闸管随流角，和主电路提高输出电压，和电机转速增加，增大和测速电路的输出电压，和电机稳定运行在设定的速度范围通过PI调节器的功能。4在系统各部分电路的设计4.1主电路的设计对电路中的各种成分的参数设置，如图3所示。按下启动按钮开关SW，使接触器KM和KM回路，常开触点闭合，其常闭触点打开，并启动按钮自锁，主电路连接，与晶闸管调速电路通过改变双向晶闸管的控制角控制的交流输出，并通过桥梁得到直流整流和滤波，同时，电机通过整流励磁电路获得激励开始工作。限制直流脉动

10、，在电路中连接平波电抗器，和电阻R3提供放电回路平波电抗器在主电路突然断了。加快制动，能耗制动是采用的设备，和制动部分由电阻R4和主电路接触器的常闭触点。电动机的励磁是由单一的整流电路供电，并防止无法控制的高速事故通过电机的励磁损耗引起的，在激励电路中，串联电流继电器KA，和动作电流可以通过调节电位器RP。4.2晶闸管触发电路的设计在主电路中的A点和B点的电压变为20V通过变压器，然后整流，约100小时半的信号发生在这两个点，并与NPN三极管通过信号分压R6和R7的放大，在三极管集电极产生过零脉冲，并捕获零通道脉冲上升沿的CCP1模块和注意发生第一时间，赶过零脉冲下降的边缘，和两者之间的时间差

11、为零的脉冲宽度，和值的一半是中点的脉冲，通过捕捉模式，我们可以准确地获得实际的过零点的交流，并在同时，我们可以利用ADC的模拟/数字转换模块将PIC16F877引脚的模拟电压RA1 / AN1所设定的晶闸管控制的角度值（设定电机的转速值），改变设定值电位器RP1和相应地改变设置的晶闸管控制角的值，并输出值转速表电路由销RA1/AN1 PIC16F877的输入，和值作为速度反馈值通过A/D转换。在单片机系统的振荡频率为4MHz，并根据特征PIC16F877订货周期，晶闸管控制角的分辨率是四分之一单片机振荡的倒数1的频率，即，在电力10ms的半波时间，控制角可以达到10000的步骤，完全实现电动机

12、的无级平滑控制。4.3测速电路设计转速表电路由光学编码盘吸积与电机转子和电脉冲放大整形电路。电脉冲频率固定的比例与电动机的转速，和通过放大整形，由光学码盘输出电脉冲从引脚RC0 /T1CK1输入PIC16F877作为标准的TTL电平，由计数TMR1计数器计算转速，并比较与预设转速和转速得到差值，与PIC16F877单片机实现PI操作这种差异的价值得到增加的控制，并将晶闸管的控制角来改变有效CCP2电机的两个端口的电压，从而控制转速。5.结论本次研究的课题直流电机双闭环调速系统的动态特性研究与仿真，是基于工程设计的方法，即用工程设计方法设计直流电动机转速、电流双闭环调速系统。根据直流电机的基本方

13、程建立调速系统的数学模型，给出动态结构框图，并用MATLAB搭建设仿真模型，进行相关参数的调试与仿真，对仿真结果进行分析、研究，验证控制方案的合理性。此次研究虽最终得到了满意的结果，但在进行系统仿真时也遇到了不少问题，主要原因在于系统建模与参数调试时没有技巧。现在我把本次仿真中获得的一些技巧作个简单的总结：(1) 系统建模时，要分为主电路和控制电路分别进行。(2) 在参数设置时，晶闸管整流桥和6脉冲触发器按仿真需要选择合适的参数，平波电抗器和直流电动机中应代入实际计算值，没有相关要求的参数取默认值即可。(3) 仿真时间的选择按实际情况而定，以出现完整的波形为前提。(4) 调节器和反馈参数按计算

14、结果代入。(5) 若双闭环仿真中出现问题，可以在开环的基础上，一步一步增加反馈环节，调节环节和限幅环节，不断调试，最终完成双闭环的仿真。(6) 参数调试时，我们还应耐心观察，认真分析，及时比较，不断优化系统。此次研究结果表明，直流电动机双闭环调速系统可以在给定调速范围内实现无静差平滑调速。由于其超调量较小，系统具有较好的稳定性、较高的稳态精度以及优良的动态性能，这不仅为直流调速实验提供了理论依据，也为其它调速系统的研究打牢了理论基础。但是其快速性要稍微差一点，这有待于以后继续研究。Double closed loop dc motor speed control system research

15、1. An overview of theDc motor has good starting and brake performance, adaptable to achieve smooth speed regulation in large scale, and dc speed regulating system in theory and practice are more mature, is the basis of the study other speed regulation system. And MATLAB software to dc speed regulati

16、ng system in a virtual environment of simulation research, not only easy to use, also greatly reduces the cost of research.Is described in this paper, the basic principle of the dc motor and speed control principle, this paper introduces the dc motor open loop and double closed-loop speed control sy

17、stem composition and the static and dynamic characteristics, and according to the basic equation of the construction of dc motor made the mathematical model of speed control system, dynamic structure diagram are given, with engineering design method of dc motor double closed loop speed control syste

18、m is designed. Finally, the MATLAB simulation software to build the simulation model of speed control system for the study of the simulation.Through the dynamic characteristics of a dc motor double closed loop speed regulation system in the research and simulation, can see clearly that dc motor doub

19、le closed loop speed regulation system has good dynamic performance, can be in the given speed range, realize the astatic smooth speed regulation,For the dc motor speed control system hardware experiments provide a theoretical basis.2. The double closed loop dc governing system research backgroundDc

20、 speed control is the modern electric drive automatic control system in the development of an earlier technology. In the 1960 s, with the emergence of thyristor, the combination of modern power electronics and control theory, computer promotes the prosperity of the electric drive control technology

21、research and application. Thyristor - dc motor speed control system for modern industry provides a highly efficient, high performance power. Although at present the rapid development of ac speed regulation, the more hasten is mature ac (alternating current) technique, and the efficiency of ac motor

22、and maintainability, the ac speed regulation is widely welcomed by users. But the dc motor speed control system, with its excellent speed regulating performance still has broad market, and based on feedback control theory of dc speed regulation principle is the basis for the control of ac speed regu

23、lation. Now the dc and ac speed regulating device is digital, using chips and software have different features, but the basic control principle has its generality.There is a big risk for those in the actual process of debugging or experimental system of expensive, generally does not allow experiment

24、s to design a good system directly. Through experimental studies, however, do not is not to design a good system directly on the actual production. So you must be on the simulation experiment research. , of course, in some cases can construct a set of device physics experiment, but this method is ve

25、ry time consuming and cost high, and in some cases, physical simulation is almost impossible. In recent years, with the rapid development of computer, USES the computer control system for mathematical simulation method has been adopted by people.But for a long time, the simulation in the field of re

26、search is focused on the establishment of simulation model is a process, namely the system model is established to design an algorithm. To make the system model for the computer, and then compiled into a computer program, and run on the computer. Thus produced a variety of simulation algorithms and

27、simulation software.Due to the model establishment and simulation study is less, so modeling often takes a long time, at the same time, the analysis of simulation results must rely on experts, and decision makers is a lack of direct guidance, thus greatly hindered the popularization and application

28、of simulation technology.Provide dynamic simulation tool Simulink in MATLAB, is the most powerful in many simulation software, one of the most outstanding, the most easy to use. It effectively solves the above problems in simulation technology. In Simulink, the modeling of the system will become ver

29、y simple, and the simulation process is interactive, so you can casually change the simulation parameters, and can immediately get the modified results. In addition, the use of MATLAB in various analysis tools, also can be the result of the simulation analysis, and visualization.Simulink can go beyo

30、nd the ideal linear model to explore more realistic models of nonlinear problem, such as friction and air resistance in the real world, the gear meshing and other natural phenomena; Simulation to the macroscopic objects, it can be to micro molecules and atoms, it can be the type of object modeling a

31、nd simulation is extensive, can is a mechanical, electronic and other real entity, also can be the ideal system, but the simulation of the complexity of the dynamic system but can small, can be continuous, discrete or hybrid. Simulink can make your computer into a lab, use it for all kinds of existi

32、ng in reality, does not exist, or even opposite system modeling and simulation.Since the 70 s, both at home and abroad in the field of electric drive extensively adopted "thyristor dc motor speed regulation technology" (hereinafter referred to as the V - M speed control system). Although t

33、oday's power semiconductor converter technology has been the development by leaps and bounds, but V - M system in industrial production are still occupies a considerable proportion. In the process of engineering design and theoretical study, to be exposed to a lot of speed control system analysi

34、s, synthesis and design problem. Traditional research methods mainly include analytical method, experimental method and simulation experiment, in which they have their respective advantages in the former two methods at the same time it still has different limitations. Along with the development of p

35、roduction technology, the electrical driving and braking, and reversing and speed control precision, speed range, static characteristic and dynamic response, etc, put forward the higher request, this requires extensive use of speed control system. As a result of the dc motor speed control and torque

36、 control performance is good, since the 1930 s, started using dc speed regulating system. Its development process is this: by the rotation of the earliest development of converter unit control for enlarger, magnetic amplifier control; Further, in the stillness of the thyristor converter device and a

37、nalog controller realize dc speed regulation; Later, with controlled rectifier and high-power transistors of PWM control circuit to realize the digital dc speed control, make the system quickness, controllability and economy enhances unceasingly. The continuous improvement of speed regulating perfor

38、mance, make the dc speed regulation system has a very wide range of applications.In industrial production, the need of high performance speed control of electric drive occasion, the dc speed regulation system, especially the double closed loop dc speed control system play an extremely important role

39、. Speed and current double closed-loop speed control system is in the 1960 s of a new type of speed control system in foreign countries. Since the 70 s, in our country's metallurgical, mechanical, manufacturing and printing and dyeing industry is increasingly widely used. Double closed loop spee

40、d control system is developed by the automatic single closed-loop speed control system. It introduced through two speed and current regulator respectively speed negative feedback and current feedback, and constitute the double closed loop system. Effectively improve the motor performance. This desig

41、n mainly adopts three-phase fully-controlled bridge rectifier circuit of dc motor power supply, and through the engineering design method for speed regulator and current regulator parameters calculation in order to achieve the speed of current double closed loop speed regulation system of a tributar

42、y of the overall implementation.3 working principle of the systemThe system is mainly composed of the main switch, the motor excitation circuit, thyristor speed control circuit (including tachometer circuit), rectifier filter circuit, flat wave reactor discharge circuit, energy consumption braking c

43、ircuit, the realization of the whole system is controlled by closed-loop PI regulator. When the main switch is closed, the small pulse current in single-phase ac gain control of thyristor speed control circuit, and the rectifier bridge, the filter for the generator and the flat wave reactor, and at

44、the same time, through the rectifier excitation circuit, ac motor inspired to begin to work. In regulating the speed of the trigger circuit potentiometer RP1 by PIC16F877 to decline, the decline of AN1 input voltage output control point of view, and the brake pipe flow Angle, and the main circuit to

45、 improve the output voltage, and the motor speed increase, increase and speed measuring circuit of the output voltage, and motor in setting speed, stable operation range by the function of the PI regulator.4. All parts of the system design of the circuit4.1 the design of the main circuitFor componen

46、ts in the circuit parameter Settings, as shown in figure 3. Press the start button switch SW, make the contactor of KM and KM circuit, the normally open contact closure, the normally closed contact is opened, and start button self-locking, main circuit connection, and thyristor speed control circuit

47、 by changing the two-way thyristor control Angle control of ac output, and dc rectifier and filter is obtained by a bridge, at the same time, the motor through rectifier excitation circuit have incentives to work. Limit the dc pulse in the circuit connection flat wave reactor, and the resistance R3

48、provide discharge circuit flat wave reactor snapped in the main circuit. To speed up the braking, energy consumption braking is to use the equipment, and brake parts by the resistor R4 and normally closed contact of main circuit contactor.The excitation of the motor is from single power rectifier ci

49、rcuit, and to prevent uncontrollable high speed accident caused by motor excitation loss, in the drive circuit, in series current relay KA, and current action can by adjusting the potentiometer RP.4.2 the design of the thyristor trigger circuitPoint A and point B in the main circuit of voltage to 20

50、 v through A transformer, then rectifier, about 100 and A half hours of signal occurred in these two points, and through the signal points with NPN R6 and R7 amplification, the triode had A zero pulse collector, and capture zero channel pulse rising along the CCP1 module and pay attention to happen

51、the first time, catch the zero pulse falling edge, and the time difference between the two is zero pulse width, and the value is half of the midpoint of pulse, by capturing mode, we can accurately obtain the actual passing zero communication, and at the same time, we can use the ADC analog/digital c

52、onversion module will analog voltage of PIC16F877 pin RA1 / AN1 set by the Angle of the thyristor control value (set motor speed value), change the set point potentiometer RP1 and change accordingly set the value of the thyristor control Angle, and the output value tachometer circuit by pin RA1 / AN

53、1 PIC16F877 input, and values as feedback speed by A/D conversion. In the single-chip microcomputer system oscillation frequency is 4 MHZ, and according to the characteristics of PIC16F877 ordering cycle, the resolution of the thyristor control Angle is a quarter of a single chip microcomputer frequ

54、ency of oscillation of the reciprocal of 1 mu, i.e., in the power of 10 ms half wave time, control Angle can reach 10000 steps, fully realize the stepless smooth control of the motor.4.3 speed measuring circuit designTachometer circuit encoded by optical disk accretion and the motor rotor and electr

55、ical pulse shaping circuit. Electrical pulse frequency fixed ratio and the rotational speed of the motor, and through the amplification plastic, by the optical encoder output electrical impulses from pin RC0 / T1CK1 input PIC16F877 as standard TTL level, by counting TMR1 counter calculation speed, a

56、nd compare with the preset rotating speed and rotating speed difference, the difference with PIC16F877 singlechip microcomputer PI operation control value increases, and the thyristor control Angle to change effective CCP2 motor voltage of two ports, so as to control speed.5 ConclusionThe study of t

57、he subject - dc motor double closed loop speed regulation system dynamic characteristic research and simulation, is based on the engineering design method of engineering design method to design dc motor speed and current double closed-loop speed control system. According to the basic equation for dc motor speed control system of mathematic model, the dynamic struc