PID控制简介中英文翻译word版

《PID控制简介中英文翻译word版》由会员分享，可在线阅读，更多相关《PID控制简介中英文翻译word版（14页珍藏版）》请在装配图网上搜索。

1、英语资料及译文About PID controlRecently automation technology is based on the concept of feedback. Elements of feedback theory consist of three parts: measurement, comparison and implementation. Measurement variables of concern, compared with expectations, with the control system to correct the error respo

2、nse.The theory and application of automatic control, the key is to make the correct measurement and comparison of how best to rectify the system.PID (proportional - integral - differential) controller as the first practical use of the controller more than 50 years of history, is still the most widel

3、y used industrial controller. Simple PID controller, the use of the system does not accurately model a prerequisite that they have become the most widely used controller.PID controller is the proportion of cells (P), integral unit (I) and the differential unit (D) component.Because of its wide range

4、 of uses, the use of flexible, has been serialized products, the use of only three parameters setting (Kp, Ti and Td) can be. In many cases, does not necessarily need all three modules, which can take 1-2 unit, but the proportion of the control unit is essential.First of all, PID broad range of appl

5、ications. Although many industrial processes or time-varying non-linear, but can be simplified through their basic non-linear and dynamic characteristics of the system over time, so that you can control the PID.Secondly, PID parameter can tune easier. That is, PID parameters Kp, Ti and Td can be bas

6、ed on the dynamic characteristics of the process of setting a timely manner. If the dynamic characteristics of the process of change, for example, changes may be caused by the load dynamic characteristics of the system changes, PID parameters can be re-tuning.Third, PID controller in practice is to

7、be improved continuously, the following are two examples of improvements.In factories, we always see a lot of loops are in manual, and because of the difficulty of the course so that the automatic mode, a smooth working. As a result of these deficiencies, the use of the industrial control system PID

8、 is always subject to product quality, safety, waste production and energy problems. PID parameter self-tuning PID parameters in order to deal with this problem setting generated. Now, the auto-tuning or self-tuning of PID controller is a business single-loop controllers and distributed control syst

9、em of a standard.In some cases the system-specific design of PID controller to control very well, but they are there are still some problems to be solved:If self-tuning should be based on the model, in order to re-PID tuning parameters online to find and maintain a good process model is more difficu

10、lt. When closed-loop works, the requirements in the process of inserting must have a test signal. This method will cause disturbance, so model-based PID parameter self-tuning is not too good in the industrial applications.If self-tuning control law based on the often difficult to load disturbance ca

11、used by the impact and dynamic characteristics of the process of the impact of changes in the distinction between the effects of so disturbed overshoot controller will have to create a self-adaptive unnecessary conversion. In addition, since the control law based on the maturity of the system is not

12、 the stability of analytical methods, the reliability of parameter tuning, there are many problems.Therefore, many self-tuning PID controller parameters work in the auto-tuning mode and not in the self-tuning mode. Auto-tuning is often used to describe the state of open-loop based on a simple proces

13、s model to determine automatic calculation of PID parameters.PID in controlling nonlinear, time-varying, coupling and parameter uncertainty and structural complexity of the process, the work is not very good. The most important thing is, if the PID controller can not control the complexity of the pr

14、ocess, regardless of how not to use transfer parameters.Despite these shortcomings, PID controller is sometimes the most simple is the best controller.At present, the level of industrial automation has become a measure of the level of modernization in all walks of life an important sign. At the same

15、 time, the development of control theory has also experienced a classical control theory, modern control theory and intelligent control theory of three stages. Classic example of intelligent control is ambiguous, such as full-automatic washing machine. Automatic control system can be divided into op

16、en-loop control systems and closed-loop control system. A control system, including controllers, sensors, transmitters, implementing agencies, input and output interfaces. Controllers output after the output interface, the implementing agencies, added to the system was charged with; control system c

17、harged with the amount, after the sensor, transmitter, through the input interface to the controller. Different control system, the sensor, transmitter, the executing agency is not the same. For example pressure sensors need to be used in pressure control system. Electric heating control system is t

18、he sensor temperature sensor. At present, PID control and PID controller or a smart controller (instrument) has a lot of products have been in practice in engineering is widely used, there are a wide range of PID controller products, major companies have developed with PID parameter self-tuning regu

19、lator function smart (intelligent regulator), which the PID controller parameters are automatically adjusted through the intelligent or self-tuning, adaptive algorithms to achieve. PID control are achieved using pressure, temperature, flow, liquid level controller, PID control functions to achieve t

20、he programmable logic controller (PLC), also enables the PC system, PID control and so on. Programmable Logic Controller (PLC) is the use of its closed-loop control module to achieve PID control, and programmable logic controller (PLC) can be connected directly with the ControlNet, such as Rockwells

21、 PLC-5 and so on. There can be the controller PID control functions, such as Rockwells Logix product line, it can be connected directly with the ControlNet, using the Internet to achieve its long-range control functions.1, Open-loop control systemOpen-loop control system is the object of the output

22、(volume control) on the controller does not affect the output. In this control system, do not rely on volume will be charged back to the formation of anti-any closed-loop circuit.2, Closed-loop control systemClosed-loop control system is characterized by the output of the system object (volume contr

23、ol) will be sent back to the impact of anti-output controller to form one or more of the closed-loop. Closed-loop control system has positive feedback and negative feedback, if the feedback signal and the system to set the value of the signal the other hand, is referred to as negative feedback, if t

24、he same polarity is called positive feedback, the general closed-loop control system using negative feedback, also known as negative feedback control system. Closed-loop control system has many examples. For example, people with negative feedback is a closed-loop control system, the eye is the senso

25、r to act as a feedback, the human body system through the constant variety of the right to make amendments to the final action. If there are no eyes, there is no feedback loops, it became an open-loop control system. Another example, when a full-automatic washing machine with a real continuously che

26、ck whether the washed clothing, and wash off automatically after the power supply, it is a closed-loop control system.3, Step response Step response refers to a step input (step function) when added to the system, the system output. Steady-state error is the system response into the steady-state, th

27、e systems desired output and actual output of the difference. The performance of control system can be stable, accurate and fast three words to describe. Stability is the stability of the system, a system must be able to work, first of all must be stable, from the step response should be a convergen

28、ce point of view; quasi-control system refers to the accuracy, control precision, stability is usually state error description, it said the system output steady-state value and the difference between expectations; fast control system refers to the rapid response, and usually to a quantitative descri

29、ption of the rise time.4, Theory and the characteristics of PID control In engineering practice, the most widely used control laws regulate the proportional, integral, differential control, referred to as PID control, also known as PID regulator. PID controller has been available for nearly 70 years

30、 of history, which in its simple structure, stable, reliable, easy to adjust and become the main industrial control technologies. When charged with the structure and parameters of the object can not completely grasp, or lack of accurate mathematical model, control theory it is difficult using other

31、techniques, the system controller structure and parameters have to rely on experience and on-site testing to determine when the application PID control of the most convenient technology. That is, when we do not fully understand the system and charged with an object, or can not be an effective means

32、of measuring system parameters to obtain the most suitable PID control technology. PID control, in practice there are PI and PD control. PID controller is the error of the system, using proportional, integral, differential calculation for the control of the volume control.The ratio of (P) control Pr

33、oportional control is one of the most simple control methods. The controllers output and input error signal proportional to the relationship. The output has the existence of steady-state error when there is only a proportional control system.Integral (I) controlIn integral control, the controllers o

34、utput and input error signal is proportional to the integral relationship. For an automatic control system, if steady-state error exists after entering the steady-state, the control system is referred to as steady-state error or having a poor system. In order to eliminate steady-state error, the con

35、troller must be the introduction of the key points. Points of error depend on the time of the points of the increase over time, will increase the integral term. In this way, even if the error is very small, integral term will increase as time increases, it increased to promote the output of the cont

36、roller so that steady-state error further reduced until zero. Therefore, the proportional + integral (PI) controller, you can make the system after entering the steady-state non-steady-state error.Differential (D) controlIn the differential control, the controllers output and input of the differenti

37、al error signal (the rate of change of error) is directly proportional to the relationship. Automatic control system to overcome the errors in the adjustment process may be unstable or even oscillation. The reason is because of greater inertial components (links) or there is lag components, can inhi

38、bit the role of error, the changes always lag behind changes in error. The solution is to inhibit the changes in the role of error in advance, that is close to zero in the error and suppress the role of error should be zero. This means that the controller only the introduction of the proportion of o

39、ften is not enough, the proportion of the role is only to enlarge the amplitude error, the current need to increase the differential item that can change the trend of prediction error, In this way, with the proportion of + differential controller, will be able to advance so that the role of inhibito

40、ry control error equal to zero or even negative, thus avoiding the amount charged with a serious overshoot. Therefore, greater inertia of the charged object or lag, the proportion of + differential (PD) controller to improve the system in the regulation of the dynamic characteristics of the process.

41、PID控制简介当今的自动控制技术都是基于反馈的概念。反馈理论的要素包括三个部分：测量、比较和执行。测量关心的变量，与期望值相比较，用这个误差纠正调节控制系统的响应。这个理论和应用自动控制的关键是，做出正确的测量和比较后，如何才能更好地纠正系统。PID（比例-积分-微分）控制器作为最早实用化的控制器已有50多年历史，现在仍然是应用最广泛的工业控制器。PID控制器简单易懂，使用中不需精确的系统模型等先决条件，因而成为应用最为广泛的控制器。PID控制器由比例单元（P）、积分单元（I）和微分单元（D）组成。它由于用途广泛、使用灵活，已有系列化产品，使用中只需设定三个参数（Kp， Ti和Td）即可。在很

42、多情况下，并不一定需要全部三个单元，可以取其中的一到两个单元，但比例控制单元是必不可少的。首先，PID应用范围广。虽然很多工业过程是非线性或时变的，但通过对其简化可以变成基本线性和动态特性不随时间变化的系统，这样PID就可控制了。其次，PID参数较易整定。也就是，PID参数Kp，Ti和Td可以根据过程的动态特性及时整定。如果过程的动态特性变化，例如可能由负载的变化引起系统动态特性变化，PID参数就可以重新整定。第三，PID控制器在实践中也不断的得到改进，下面是两个改进的例子。在工厂，总是能看到许多回路都处于手动状态，原因是很难让过程在“自动”模式下平稳工作。由于这些不足，采用PID的工业控制系

43、统总是受产品质量、安全、产量和能源浪费等问题的困扰。PID参数自整定就是为了处理PID参数整定这个问题而产生的。现在，自动整定或自身整定的PID控制器已是商业单回路控制器和分散控制系统的一个标准。在一些情况下针对特定的系统设计的PID控制器控制得很好，但它们仍存在一些问题需要解决：如果自整定要以模型为基础，为了PID参数的重新整定在线寻找和保持好过程模型是较难的。闭环工作时，要求在过程中插入一个测试信号。这个方法会引起扰动，所以基于模型的PID参数自整定在工业应用不是太好。如果自整定是基于控制律的，经常难以把由负载干扰引起的影响和过程动态特性变化引起的影响区分开来，因此受到干扰的影响控制器会产

44、生超调，产生一个不必要的自适应转换。另外，由于基于控制律的系统没有成熟的稳定性分析方法，参数整定可靠与否存在很多问题。因此，许多自身整定参数的PID控制器经常工作在自动整定模式而不是连续的自身整定模式。自动整定通常是指根据开环状态确定的简单过程模型自动计算PID参数。PID在控制非线性、时变、耦合及参数和结构不确定的复杂过程时，工作地不是太好。最重要的是，如果PID控制器不能控制复杂过程，无论怎么调参数都没用。虽然有这些缺点，PID控制器是最简单的有时却是最好的控制器目前工业自动化水平已成为衡量各行各业现代化水平的一个重要标志。同时，控制理论的发展也经历了古典控制理论、现代控制理论和智能控制理

45、论三个阶段。智能控制的典型实例是模糊全自动洗衣机等。自动控制系统可分为开环控制系统和闭环控制系统。一个控制系统包括控制器、传感器、变送器、执行机构、输入输出接口。控制器的输出经过输出接口、执行机构，加到被控系统上；控制系统的被控量，经过传感器，变送器，通过输入接口送到控制器。不同的控制系统，其传感器、变送器、执行机构是不一样的。比如压力控制系统要采用压力传感器。电加热控制系统的传感器是温度传感器。目前，PID控制及其控制器或智能PID控制器（仪表）已经很多，产品已在工程实际中得到了广泛的应用，有各种各样的PID控制器产品，各大公司都开发了具有PID参数自整定功能的智能调节器 (intellig

46、ent regulator)，其中PID控制器参数的自动调整是通过智能化调整或自校正、自适应算法来实现。有利用PID控制实现的压力、温度、流量、液位控制器，能实现PID控制功能的可编程控制器(PLC)，还有可实现PID控制的PC系统等等。 可编程控制器(PLC) 是利用其闭环控制模块来实现PID控制，而可编程控制器(PLC)可以直接与ControlNet相连，如Rockwell的PLC-5等。还有可以实现 PID控制功能的控制器，如Rockwell 的Logix产品系列，它可以直接与ControlNet相连，利用网络来实现其远程控制功能。1、开环控制系统开环控制系统是指被控对象的输出(被控制量

47、)对控制器的输出没有影响。在这种控制系统中，不依赖将被控量反送回来以形成任何闭环回路。2、闭环控制系统闭环控制系统的特点是系统被控对象的输出(被控制量)会反送回来影响控制器的输出，形成一个或多个闭环。闭环控制系统有正反馈和负反馈，若反馈信号与系统给定值信号相反，则称为负反馈，若极性相同，则称为正反馈，一般闭环控制系统均采用负反馈，又称负反馈控制系统。闭环控制系统的例子很多。比如人就是一个具有负反馈的闭环控制系统，眼睛便是传感器，充当反馈，人体系统能通过不断的修正最后作出各种正确的动作。如果没有眼睛，就没有了反馈回路，也就成了一个开环控制系统。另例，当一台真正的全自动洗衣机具有能连续检查衣物是否

48、洗净，并在洗净之后能自动切断电源，它就是一个闭环控制系统。3、阶跃响应阶跃响应是指将一个阶跃输入（step function）加到系统上时，系统的输出。稳态误差是指系统的响应进入稳态后，系统的期望输出与实际输出之差。控制系统的性能可以用稳、准、快三个字来描述。稳是指系统的稳定性，一个系统要能正常工作，首先必须是稳定的，从阶跃响应上看应该是收敛的；准是指控制系统的准确性、控制精度，通常用稳态误差来描述，它表示系统输出稳态值与期望值之差；快是指控制系统响应的快速性，通常用上升时间来定量描述。4、PID控制的原理和特点在工程实际中，应用最为广泛的调节器控制规律为比例、积分、微分控制，简称PID控制，

49、又称PID调节。PID控制器问世至今已有近70年历史，它以其结构简单、稳定性好、工作可靠、调整方便而成为工业控制的主要技术之一。当被控对象的结构和参数不能完全掌握，或得不到精确的数学模型时，控制理论的其它技术难以采用时，系统控制器的结构和参数必须依靠经验和现场调试来确定，这时应用PID控制技术最为方便。即当我们不完全了解一个系统和被控对象，或不能通过有效的测量手段来获得系统参数时，最适合用PID控制技术。PID控制，实际中也有PI和PD控制。PID控制器就是根据系统的误差，利用比例、积分、微分计算出控制量进行控制的。比例（P）控制比例控制是一种最简单的控制方式。其控制器的输出与输入误差信号成比

50、例关系。当仅有比例控制时系统输出存在稳态误差。积分（I）控制在积分控制中，控制器的输出与输入误差信号的积分成正比关系。对一个自动控制系统，如果在进入稳态后存在稳态误差，则称这个控制系统是有稳态误差的或简称有差系统。为了消除稳态误差，在控制器中必须引入“积分项”。积分项对误差取决于时间的积分，随着时间的增加，积分项会增大。这样，即便误差很小，积分项也会随着时间的增加而加大，它推动控制器的输出增大使稳态误差进一步减小，直到等于零。因此，比例+积分(PI)控制器，可以使系统在进入稳态后无稳态误差。微分（D）控制在微分控制中，控制器的输出与输入误差信号的微分（即误差的变化率）成正比关系。自动控制系统在克服误差的调节过程中可能会出现振荡甚至失稳。其原因是由于存在有较大惯性组件（环节）或有滞后组件，具有抑制误差的作用，其变化总是落后于误差的变化。解决的办法是使抑制误差的作用的变化“超前”，即在误差接近零时，抑制误差的作用就应该是零。这就是说，在控制器中仅引入 “比例”项往往是不够的，比例项的作用仅是放大误差的幅值，而目前需要增加的是“微分项”，它能预测误差变化的趋势，这样，具有比例+微分的控制器，就能够提前使抑制误差的控制作用等于零，甚至为负值，从而避免了被控量的严重超调。所以对有较大惯性或滞后的被控对象，比例+微分(PD)控制器能改善系统在调节过程中的动态特性。13