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Process Control College of Automation Chongqing University1Dynamic ResponseOutline:轮廓⏹Brief Review of the Dynamic Response简要回顾动态响应⏹First Order Models for Processes一阶模型的过程⏹Seconds Order Model for Processes二阶模型过程⏹Models for Process with Dead-Time死区时间的过程模型⏹Higher Order Models and Approximation高阶模型和近似⏹Special Features of Lead-Lag Process滞后过程的特殊特色The First Order Model of a ProcessQ,C inC1V1Whereis time constantThe general form of the 1st order model一阶模型的一般形式Steady state gain稳态增益The Second Order Model of a ProcessWhereare time constantsThe general form of the 2st order modelQ,C inV 1C 1C 2V 22'''22121222()()indC dC C t C dtdtττττ+++=)(01222t bx y a dtdya dt y d a =++withWith an ≠ 0和零初始条件Analysis of the 1st Order ProcessStep responsetransfer functionConsider a step input, x(t) =Mu(t), and X(s) = M/sThe output isThe time domain function isAnalysis of the 1st Order Process Step response阶跃响应Property 1性质1y increases from 0 to a new steadystate M K, thus self-regulatingy增加从0到一个新的稳态MK,从而自我调节Analysis of the 1st Order Process Step responseProperty 2性质2Steady state gain K = y/M,The larger gain K, the moresensitive is the output to thechange in the input增益K越大，输出随输入变化就越敏感Analysis of the 1st Order Process Step responseProperty 3At t=τ, the output isy =0.632MKThe formula above can be used to estimate space timeτ上面的公式可以用来估计空间时间τAnalysis of the 1st Order ProcessStep responseThe time domain function is 时域功能Property 4The shorter the space time τ, the faster reaches the new steady state0.25, 0.5, 1, 2Analysis of the 1st Order ProcessImpulse response脉冲响应transfer function传递函数Consider an impulse input, x(t) =M (t), and X(s) = M 考虑一个脉冲输入The output is Inverse transform反变换The output increases instantaneously at time t = 0, and decays exponentially to zero.输出瞬间增加在时间t= 0，且呈指数衰减到零Analysis of the 1st Order ProcessIntegrating process: Non-self-regulating 整合过程：非自我调节a= 0Laplace transformTime domain时域Analysis of the 1st Order Process⏹Integrating process: Non-self-regulating☐With step response, the output is a ramp function阶跃响应，输出的是一个斜坡函数☐With impulse response▪The output will not return to its original steady state▪输出不会回到原来的稳定状态▪Output value is the accumulation of what is added▪输出值会累积增加⏹Example can be☐Charging a capacity充电容量☐Filling up a tank 填充的水池Example: Show that a storage tank with pumps at its inlet and outletis a integrating process 表明储罐泵在其进口和出口是一个整合过程Mass balance of a continuous flow mixed tankat constant density is :质量守恒方程，在密度不变的情况下whereq in and q are the flow rates of the inlet and outlet q in and q 是进口和出口的流动速率A is the cross-section 截面h is the liquid level 液位hExample (cont.)⏹At steady state, we can define deviation variables⏹在稳定状态下,我们可以定义偏差变量h’=h – h s, q’in =q in – q s, and q’ =q – q s⏹Mass balance becomes⏹The general solution一般解Example (cont.)⏹The transfer function⏹Step input in either q’in or q’ Leading to a ramp response, thus no steady state阶跃输入q‘in 或q’，导致斜坡响应，因此，没有稳定的状态⏹The tank will overflow, while outlet slows down ⏹容器将溢出,当出口关小Setting q’in=constant, the transfer function is⏹The tank will be drained, while outlet speeds up ⏹容器内液体将流干，当流出速度增加Example (cont.): Visualize the integrating process 可视化的积分过程 pump 泵q inqq inqNon-Self-RegulatingThe tank will overflow, while step-in occursOther Typical1st Order ProcessesE= Voltage, 电压z = Position,K’= Spring constant弹性系数,f = friction coefficient摩擦系数Other Typical 1st Order Processes An Extra Example (cont.):RC i iVccV V dtdV RC -=where τ = RC is time constant K = 1 is steady state gain x(t) = V s is the input )1(/τt s c e V V --=Charging: Discharging:τ/t s c e V V -=Other Typical 1st Order ProcessesAn Extra Example (cont.):RCi iV )1(/τt s c e V V --=Charging:Discharging:τ/t s c e V V -=Analysis of the 2nd Order ProcessCorresponding Laplace Transform相应的拉普拉斯变换Where 说明：damping ratio阻尼比natural period of oscillation自然振荡周期natural frequency固有频率Analysis of the 2nd Order Process Characteristic polynomial特征多项式The poles are 极点是：Noticing again that a stable process requires再一次注意到一个稳定的过程需要ζ>τ)0(i.e.,>Three Cases of the PolesCase 1. overdamped process 过阻尼过程In term of the two time constants 依据两个时间常数Time constant can be derived below 被推倒21ττ and 1>ζ21ττ and or,In the case of having real poles, we have 在实极点的情况下，我们有Three Cases of the PolesCase 1. overdamped process 过阻尼过程How about the forms of transfer function in term of ? 传递函数有哪种形式按照/1 and /121ττ-- 1>ζStep response in term of the time constant 阶跃响应下的时间常数τResponse is sluggish compared with underdamped or critically damped processes 响应比较缓慢与欠阻尼或临界阻尼的进程相比Three Cases of the Poles三种极点ζCase 1. overdamped process过阻尼1>可视为时间常数Three Cases of the PolesCase 3. underdamped process 欠阻尼 10<≤ζStep responseBeing rearranged as被调整为The real part determines the exponential decay, thus the amount of can be considered as the time constant 决定了指数衰减，从而可视为时间常数τζ-τζTwo conjugate poles are两个共轭极点是τζτζ21-±-j based on 基于 τζ-τζKey Features of Underdamped Process 欠阻尼过程的主要特点(2) making control system design specifications with respect to the dynamic response 制作动态响应的控制系统设计规范⑴ fitting experimental data in the measurements of natural period and damping factor ,把测量自然周期和阻尼因子拟合过后的实验数据Features Derived from the figure for:图的特征Key Features of Underdamped Process1. Overshoot超调⏹The overshoot increases as ζ becomes smaller⏹The OS becomes zero as ζ approaches 1⏹The time to reach the peak value is Peak Time峰值时间T p⏹The time to hit the final value of y(t) is Rise Time上升时间 t rKey Features of Underdamped Process2. Frequency and Period周期⏹Noting that（注意）T=2 T p⏹The unit of the frequency is radian/time频率的单位是弧度/时间 The relationship between frequency and periodKey Features of Underdamped Process3. Settling time 调节时间 T s⏹The dominant factor forcing theoscillation to decay to zero is震荡衰减到0的主导因素是：)/(t e τζ-in ⏹To settle with ±5% of the final value is T s =3/(ζ/τ)⏹±5%误差带所需要的调节时间 T=⏹To settle with ±2% of the final value is T s =4/(ζ/τ)n ω1Key Features of Underdamped Process 4. Decay Ratio 衰减率OS为超调（overshoot）⏹The decay ratio is the square of the overshoot⏹Both quantities are functions of ζ only这两个量只是ζ函数（调节时间和衰减率）Other Typical 2nd Order ProcessesE= Voltage,z = Position,K’= Spring constant,f = Friction CoefficientM = Massh = forceProcesses with Dead Time过程控制的延迟时间The time delay between the input and output in a process输入与输出的时间延迟⏹Being also called dead time or transport lag传输延迟⏹The Laplace transform of a time delay is an exponentialfunction指数函数Processes with Dead Time A Simple ExampleProcesses with Dead Time⏹The 1nd and 2nd order models have the s-domain function S域函数⏹Td是延迟时间and⏹Dealing with the exponential functions处理的指数函数⏹Estimation with Taylor series expansion泰勒级数展开估计Estimation with Padé approximation (higher accuracy) Padé逼近估计（精度更高）Processes with Dead Time⏹The 1nd order Padé approximation⏹The Denominator introduces a negative pole, probably impacting thecharacteristic polynomial of the original process介绍了负极分母,可能影响特征多项式的原工艺⏹The numerator has a positive zero, making the process unstable分子有一个积极的零,使过程不稳定⏹The 2nd order Padé approximation⏹Having two negative poles and at least one zero⏹有两个负极点和至少一个零点Processes with Dead TimeExample: Using the 1nd order Padé approximation帕德近似to plot the step response of the 1st process with dead time 使用的一介帕德近似逼近延迟时间绘制的第一过程的阶跃响应Padé approximationObservation: the approximation is acceptable at larger timescompared with the original transfer function.逼近的函数和原函数相比可以接受Processes with Dead TimeExample (cont.) Generating the required plot 生成需要的图形（MATLAB ）Pad é approximationProcesses with Dead TimeThe response of the dead time processProcesses with Dead TimeTwo plants have different intermediate variables but have the same input-output behavior!两个工厂有不同的中间变量,但有相同的投入产出的行为!Processes with Dead TimeTwo plants have different intermediate variables but have the same input-output behavior!Higher Order Process⏹All linearized higher order system can be broken down into the 1st and 2nd order units所有线性化高阶系统可以分成一阶和二阶单位⏹The complex process like two interacting tanks can be formulated in coupled differential equations复杂的过程，像两个相互作用的容器能制定耦合微分方程⏹All these problems are considered linear⏹所有这些问题都能被线性化Higher Order ProcessA series of well-mixed vessels where the volumetric flow rate, and the respective volumes are constant 一系列混合容器，其中体积流速，和各自的容量是恒定的n 1n n n c c tc τ-=-d dHigher Order Process⏹A series of well-mixed vessels (cont.)混合容器☐The steady state gain is unity in the process 在过程中稳态增益不变☐The more tanks in the series, the more sluggish is the response of the overall process 容器越多，整个响应过程的滞后越长☐Processes that are products of the 1st order functions are called as multicapacity processes 多容量过程☐If all of space time （空间时间关系）are equal, nτττ=== (21)Higher Order ProcessExample: showing how the unit step response C n (t) becomes more sluggish as n increases 显示单位阶跃响应Cn(t)随著n 增加变得更加缓慢Higher Order ProcessExample (cont.) the Matlab code for the plot 绘制图形的MATLAB 代码The response is obviously slower, as n increses The curves can be approximated by the 1st order model with dead time 这些特征曲线可近似为滞后的一阶模型3=τApproximation of Higher Order Process⏹Higher models☐Being factored into the form partial functions考虑部分函数的形式☐Time constants have a large enough difference时间常数有很大的的差异⏹The reduced-order model approximation☐Throwing away the small time scale terms☐扔掉小时间关系☐Retaining the ones with dominant poles (larger time constants)☐固定主导极点(大时间常数)。
Unit 1 Introduction to Process ControlIn recent years the performance requirements for process plants have become increasingly difficult to satisfy. Stronger competition, tougher environmental and safety regulations and rapidly changing economic conditions have been key factors in the tightening of plant product quality specifications. A further complication is that modern processes have become more difficult to operate because of the trend toward larger, more highly integrated plants with smaller surge capacities between the various processing units. Such plants give the operators little opportunity to prevent upsets from propagating from one unit to other interconnected units. In view of the increased emphasis placed on safe. efficient plant operation, it is only natural that the subject of process control has become increasingly important in recent years. In fact, without process control it would not be possible to operate most modern processes safely and profitably, while satisfying plant quality standards.近年来，对于过程系统的执行的必要条件越来越难满足了，在紧缩的工厂产品质量规范中，强大的竞争，严峻的环境和安全规范，快速变化的经济状况，这些重要因素都是我们必须考虑的。
目录第一篇 SPC概述 (1)1．1SPC定义 (1)1．2SPC主要用途 (1)第二篇 DOSOFTSPC产品介绍 (2)2．1D OSOFT SPC产品体系 (2)2．2D OSOFT SPC产品特点 (3)2．3D OSOFT SPC功能特色 (4)2．4D OSOFT SPC功能介绍 (6)2．4．1 DosoftSPC数据采集 (6)2．4．2 DosoftSPC过程监控 (8)2．4．3 DosoftSPC质量追溯 (9)2．4．4 DosoftSPC统计分析 (10)2．4．5 DosoftSPC质量改进 (17)2．5D OSOFT SPC操作流程 (24)2．6D OSOFT SPC软件优势 (25)第三篇常见问题 (26)第一篇SPC概述1．1 SPC定义SPC（Statistical Process Control）中文译名“统计过程控制系统”，是应用于企业质量管理的至为有效的方法和工具，六西格玛的核心工具之一。
它运用数理统计的方法，对过程进行监控，对检测所得的各种质量数据进行统计分析，保证过程的稳定，提高过程能力，帮助质量管理人员有效的分析和解决质量问题，不断提升品质，有效地减少不良品的产生，从而大幅降低企业的成本，提高企业的经济效益和核心竞争力。
1．2 SPC主要用途企业质量管理三境界：●质量检验阶段：企业只进行质量的检验，不进行分析●质量分析阶段：企业采用EXCEL等简单工具，进行部分，不定期的问题分析●质量控制阶段：建立质量控制平台，进行预警，监控，分析，控制的闭环控制系统。
1、采用国际标准的质量过程控制系统，建立了从数据采集，过程监控，图形分析，过程控制的闭环控制平台——提高管理水平，加强质量意识。
2、提供了基于网络和数据库的数据分析工具，改变传统手工的简单烦琐图形绘制——提高办公效率，降低劳动强度，创造个性化工作环境。
3、建立统一分析标准，固化先进管理模式，保存完整质量数据——避免人为因素，减少员工流失带来的损失，保证系统可持续稳定运行。
重⼤⾃动化过程控制_process_control_中⽂_翻译_第⼀章Process Control Systems过程控制系统College of Automation,Chongqing University过程控制⾃动化重庆⼤学1Outline of the IntroductionW hat Is Process Control?DefinitionA few examples and forms⼀些例⼦和形式W hat Does It Do?Differences from automatic control theory⾃动控制理论的差异?W hat to be controlled?How Does It Do?如何实现Formulating the problem制定问题Control Equipment and Process Equipment控制设备和⼯艺设备?M odeling the process of the Problem建模过程的问题Introduction to Process Control Operator’s View of Process Control操作员的观点的过程控制A Day in aLife of a PlantOperatorDefinitionThe technology ofcontrolling a series of events to transform a material into a desired end product is called process control.控制技术的⼀系列事件把资料达到所希望的最终产品,被称为过程控制Short examples:M aking of fire for cooking rice (primitive and modern)The fly-ball governor for steam engine control (1774)短的例⼦:让⽕煮⽶饭(原始的和现代)州长的fly-ball蒸汽发动机控制(1774)Tendency of industrial process controlbeing computerized,being automatized , andbeing instrumented w ith smart sensors and M EM S⼯业过程控制的趋势在计算机化,在潜意识中⾃动使⽤,被装备智能传感器和微机电系统(M EM S)A Few Examples1.Flow Control in Oil refinery Plant:Do w e run around the plant to adjust the valves w hen required?流量控制,是炼油⼚植物:我们到处跑植物调节阀门在需要的时候吗?A Few Examples2. pH ControlManual⼿册AutomatedpH controlA Few Examples:3. Room temperature controlA Few Example4. Watt Centralfugal Speed Governor ⽡特Centralfugal调速器A Few Examples5. Level Control液位控制A Few Examples6. Cross Direction ProceControl⼗字⽅向过程控制Several hundred sensors andactuators,M illisecond operation,Controlling paper thickness tow ithin microns!⼏百传感器和执⾏器,微操作,控制纸张厚度和在微⽶!A Few Examples7. Discrete M anufacturing Processes 离散型制造过程A Few Examples8. Typical continuous processes典型的连续过程A Few Examples9. Typical non-continuous processesA Few Examples10. A Semi-Continuous Process半连续过程How large shouldthe tank volume be?油箱体积是多⼤呢？Sample-Plant: M ill W ide Process Control轧机⼴泛的过程控制Sample Softw are: Honeyw ell Intellimap样品软件:霍尼韦尔IntellimapW hat Is Process Control?Summary of the Examples- Forms总结的例⼦-形式Discrete M anufacturing, M otion, and Packaging离散型制造、运动、和包装Robotic Assembly Line in Automotive Production机械的汽车⽣产流⽔线M etal Stamping for the discrete pieces of product 五⾦冲压为离散件产品Continuous Production of Fuels, Chemicals连续⽣产的燃料、化学品Room Temperature Control室温控制Nucleus Chemical Reactor核化学反应器Batch Production of intermediate/end products批量⽣产中间/终端产品Adhesives and gluesFood, Beverages, andM edicineW hat Is Process Control?Tedency: Being Compueterized, Automatized, and Instrumented by smart sensors and M EM S计算机化，⾃动化，和动态化由智能传感器和微机电系统Sensors, local indicators,and valves in the process传感器、当地的指标,和阀门在这个过程中Valve openingdetermined by thesignal from computerDisplays of variables, calculations, commands to valves andhistorical data are in the centralized control center.显⽰变量的影响,计算,命令对阀门和历史数据是在中央控制中⼼Differences from Automatic Control Theory⾃动控制理论的差异?Using Control Theory as a ToolSolving the Real-W orld Problems forM aintaining controlled variables at the desired values保持控制变量在期望值M anufacturing products w ith consistent quality w hen raw material properties change⽣产质量稳定的产品，原料性质改变时？Responding dangerous situations w ith given time危险的情况下和给定的时间响应Being Specialized by transducer作为专业的传感器Smart sensorsM EM S 微机电系统。
