Manuel d'utilisation / d'entretien du produit PID Control Toolkit 371685C-01 du fabricant National Instruments
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LabWindows TM /CVI TM PID Control Toolkit User Manual LabWindows/CVI PID Control T oolkit User Manual May 2008 371685C-01.
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© National Instruments Corporation v LabWi ndows/CVI PID Contro l Toolkit User Manual Contents About This Manual Conventions ............ .............. .............. ........... .............. ............... .............. .............. ....... v ii Related Documentation .
Contents LabWindows/CVI PID Control Toolkit User Manual vi ni.com Converting between Percentage of Full S cale and Engineering Units ........... 3-9 Using PID on Real-Time (RT) Targets ......................... .............. .............. ...... 3-10 Using PID with DAQ Devices .
© National Instruments Corporation vii LabWi ndows/CVI PID Contro l Toolkit User Manual About This Manual The LabWindows/CVI PID Contro l Toolkit User Manual descri bes the PID Control T oolkit for LabWindo ws ™ /CVI ™ . The manual describes the features, functions, and operation of the toolkit.
© National Instruments Corporation 1-1 LabWin dows/CVI PID Control T oolkit User Manual 1 Over view of the PID Control T oolkit This chapter describes how to install the toolkit and describes Proportional-Integral-Deriv ati ve (PID) control applications.
Chapter 1 Overview of th e PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 1-2 ni.com Activation Instructions The first time you launch LabWindo ws/CVI after installing the PID Co ntrol T oolkit, you are prompted to activ ate the toolkit.
Chapter 1 Overview of th e PID Control T oolkit © National Instruments Corporation 1-3 LabWin dows/CVI PID Control T oolkit User Manual PID Control Currently , the PID algorithm is the most comm on control algorithm used in industry .
© National Instruments Corporation 2-1 LabWin dows/CVI PID Control T oolkit User Manual 2 PID Algorithms This chapter explains the f ast PID, precise PID, and autotuning algorithms.
Chapter 2 PID Algorithms LabWindows/CVI PID Control T oolkit User Manual 2-2 ni.com Implementing the PID Algor ithm with the PID Functions This section describes how the PID Control T oolkit fu nctions implement the fast (positional) PID algorith m. The f ast PID algo rithm is th e default algorithm used in the PID Control T oolkit.
Chapter 2 PID Algorithms © National Instruments Corporation 2-3 LabWin dows/CVI PID Control T oolkit User Manual Output Limiting The actual controller output is limited to the range speci fied for control output, as fo llows: and The follo wing formula sho ws the prac tical model of the PID controller .
Chapter 2 PID Algorithms LabWindows/CVI PID Control T oolkit User Manual 2-4 ni.com The Precise PID Algorithm This section describes how the PID Control T o olkit functions implem ent the precise PID algorithm.
Chapter 2 PID Algorithms © National Instruments Corporation 2-5 LabWin dows/CVI PID Control T oolkit User Manual T rapezoidal Integration T rapezoidal integration is used to a void shar p changes in integral action when there is a sudden change in the PV or SP .
Chapter 2 PID Algorithms LabWindows/CVI PID Control T oolkit User Manual 2-6 ni.com Figure 2-2 illustrates the auto tuning procedure excited by the setpoint relay experiment, which connects a relay and an e xtra feedback si gnal with the SP . Noti ce that the PID Library autotuning functions directly implement this process.
Chapter 2 PID Algorithms © National Instruments Corporation 2-7 LabWin dows/CVI PID Control T oolkit User Manual Table 2-2. T uning Formula under P-Only Control (Normal) Contr oller K c T i T d P 0.2 K u — — PI 0.18 K u 0.8 T u — PID 0.25 K u 0.
Chapter 2 PID Algorithms LabWindows/CVI PID Control T oolkit User Manual 2-8 ni.com Note During tuning, the process remains under closed-loop PID control . It is not necessary to switch off the e xisting controll er and perform the experiment under open-loop conditions.
© National Instruments Corporation 3-1 LabWin dows/CVI PID Control T oolkit User Manual 3 Using the PID Control T oolkit This chapter contains the basic information you need to design a control strategy using the PID Control T oolkit functions.
Chapter 3 Using the PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 3-2 ni.com T uning Controllers Manually The following controller tuning procedures are based on the work of Zi .
Chapter 3 Using the PID Control T oolkit © National Instruments Corporation 3-3 LabWin dows/CVI PID Control T oolkit User Manual Open-Loop (Step T est) T uning Procedure The open-loop (step test) tuning procedure as sumes that you can model an y process as a first-order lag and a pure deadtime.
Chapter 3 Using the PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 3-4 ni.com Using the PID Librar y The following sections describe how to use th e PID Library to implement a control strateg y .
Chapter 3 Using the PID Control T oolkit © National Instruments Corporation 3-5 LabWin dows/CVI PID Control T oolkit User Manual The fast PID algorithm is faster and simpler than the precise PID algorithm. Use the fast algorithm in fast control lo ops.
Chapter 3 Using the PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 3-6 ni.com Using PID with Autotuning Y ou can use autotuning to improv e controller pe rformance. There are tw o ways in which you can autotune a controller . • Wizard-Based Autotuning —Y ou can use the PID Autotuning W izard to tune the parameters.
Chapter 3 Using the PID Control T oolkit © National Instruments Corporation 3-7 LabWin dows/CVI PID Control T oolkit User Manual If you are using LabW indows/CVI 8.0 and later , click Add Addi tional Mod ule in the Drivers & Components tab of the Edit Installer dialog box.
Chapter 3 Using the PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 3-8 ni.com Using PID with Lead-Lag The lead-lag compensator uses a positional algorithm that approximates a true exponential lead-lag. Feed forwar d control schemes often use this kind of algorithm as a dynamic compensator .
Chapter 3 Using the PID Control T oolkit © National Instruments Corporation 3-9 LabWin dows/CVI PID Control T oolkit User Manual Y ou can use the setpoint profiler as follo ws: 1.
Chapter 3 Using the PID Control T oolkit LabWindows/CVI PID Control T oolkit User Manual 3-10 ni.com value of 1 produces an output of 10 fo r a difference between the SP and PV of 10, regardless of the output range and setpoint range.
Chapter 3 Using the PID Control T oolkit © National Instruments Corporation 3-11 LabWi ndows/CVI PID Control T oolkit User Manu al The control loops can be timed in the following ways: • Software-Timed —In software-timed control loop s, the timing is controlled by the software loop rate.
© National Instruments Corporation A- 1 LabWin dows/CVI PID Control T oolkit User Manual A References The Instrument Society of America (ISA), the organization that sets standards for process control.
© National Instruments Corporation B- 1 LabWin dows/CVI PID Control T oolkit User Manual B T echnical Support and Professional Ser vices Visit the following sections of the award-winning National Instruments Web site at ni.com for technical support and professional services: • Support —T echnical support resources at ni.
Appendix B T echnical Support and Professional Services LabWindows/CVI PID Control T oolkit User Manual B-2 ni.com If you searched ni.com and could not find the answers you need, contact your local off ice or NI corporate h eadquarters. Phone numbers for our worldwide of f ices are listed at the front of this manual.
© National Instruments Corporation G-1 LabWin dows/CVI PID Control T oolkit User Manual Glossar y A algorithm A prescribed set of well-defined rules or processes for the solut ion of a problem in a finite number of steps.
Glossary LabWindows/CVI PID Control T oolkit User Manual G-2 ni.com D damping The progressiv e reduction or suppression of oscillation in a device or system. dead time (T d ) The interval of time, expressed in minutes, between initiation of an input change or stim ulus and the start of the resulting observable response.
Glossary © National Instruments Corporation G-3 LabWin dows/CVI PID Control T oolkit User Manual I Instrument Societ y of America (ISA) The organization that sets standards for process con trol instrumentation i n the United States. integral (control) action Control action in wh ich the output is proportional to the time int egral of the input.
Glossary LabWindows/CVI PID Control T oolkit User Manual G-4 ni.com O output limi ting Pre ve nting a controller’ s output from trav eling beyond a desired maximum range. ov ershoot The maximum excursion beyond the fi nal steady-state value of output as the result of an in put change.
Glossary © National Instruments Corporation G-5 LabWin dows/CVI PID Control T oolkit User Manual R ramp The total (transient plus steady-state) time respon se resulting from a sudden increase in the rate of change from zero to some f inite v alue of input stimulus.
© National Instruments Corporation I-1 LabWi n dows/CVI PID Control T oolkit User Manual Index A applications, 1-3 autotuning, 3-6 classic, 3-6 procedure, 3-6 wizard based, 3-6 distributing applicati.
Index LabWindows/CVI PID Control T oolkit User Manual I-2 ni.com I installation instructions, 1-1 instrument driv ers (NI resources), B-1 integral action, 2-1 integral time, 2-1 K Kno wledgeBase, B-1 L lag compensation, 3-8 lead compensation, 3-8 lead-lag compensator, 3-8 N National Instruments support and services, B-1 Nichols, N.
Index © National Instruments Corporation I-3 LabWi n dows/CVI PID Control T oolkit User Manual S setpoint, 1-3 relay experiment, 2-6 software (NI resources), B-1 step test tuning procedure, 3-3 suppo.
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Si vous n'avez pas encore acheté National Instruments PID Control Toolkit 371685C-01 c'est un bon moment pour vous familiariser avec les données de base sur le produit. Consulter d'abord les pages initiales du manuel d'utilisation, que vous trouverez ci-dessus. Vous devriez y trouver les données techniques les plus importants du National Instruments PID Control Toolkit 371685C-01 - de cette manière, vous pouvez vérifier si l'équipement répond à vos besoins. Explorant les pages suivantes du manuel d'utilisation National Instruments PID Control Toolkit 371685C-01, vous apprendrez toutes les caractéristiques du produit et des informations sur son fonctionnement. Les informations sur le National Instruments PID Control Toolkit 371685C-01 va certainement vous aider à prendre une décision concernant l'achat.
Dans une situation où vous avez déjà le National Instruments PID Control Toolkit 371685C-01, mais vous avez pas encore lu le manuel d'utilisation, vous devez le faire pour les raisons décrites ci-dessus,. Vous saurez alors si vous avez correctement utilisé les fonctions disponibles, et si vous avez commis des erreurs qui peuvent réduire la durée de vie du National Instruments PID Control Toolkit 371685C-01.
Cependant, l'un des rôles les plus importants pour l'utilisateur joués par les manuels d'utilisateur est d'aider à résoudre les problèmes concernant le National Instruments PID Control Toolkit 371685C-01. Presque toujours, vous y trouverez Troubleshooting, soit les pannes et les défaillances les plus fréquentes de l'apparei National Instruments PID Control Toolkit 371685C-01 ainsi que les instructions sur la façon de les résoudre. Même si vous ne parvenez pas à résoudre le problème, le manuel d‘utilisation va vous montrer le chemin d'une nouvelle procédure – le contact avec le centre de service à la clientèle ou le service le plus proche.
