1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 61131-7:2001 IEC 61
2、131-7:2000 The European Standard EN 61131-7:2000 has the status of a British Standard ICS 25.040.40; 35.060; 35.240.50 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Programmable controllers Part 7: Fuzzy control programmingThis British Standard, having been prepared under th
3、e direction of the Electrotechnical Sector Committee, was published under the authority of the Standards Committee and comes into effect on 15 April 2001 BSI 04-2001 ISBN 0 580 36843 2 BS EN 61131-7:2001 Amendments issued since publication Amd. No. Date Comments National foreword This British Standa
4、rd is the official English language version of EN 61131-7:2000. It is identical with IEC 61311-7:2000. The UK participation in its preparation was entrusted by Technical Committee GEL/65, Measurement and control, to Subcommittee GEL/65/2, Elements of systems, which has the responsibility to: aid enq
5、uirers to understand the text; present to the responsible international/ European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations
6、 represented on this subcommittee can be obtained on request to its secretary. From 1 January 1997, all IEC publications have the number 60000 added to the old number. For instance, IEC 27-1 has been renumbered as IEC 60027-1. For a period of time during the change over from one numbering system to
7、the other, publications may contain identifiers from both systems. Cross-references Attention is drawn to the fact that CEN and CENELEC Standards normally include an annex which lists normative references to international publications with their corresponding European publications. The British Stand
8、ards which implement these international or European publications may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to i
9、nclude all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, th
10、e EN title page, pages 2 to 57 and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued.EUROPEAN STANDARD EN 61131-7 NORME EUROPENNE EUROPISCHE NORM December 2000 CENELEC European Committee for Electrotechnical Standardization Comit Europen de
11、 Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B - 1050 Brussels 2000 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61131-7:2000 E ICS 35.240.50;25.040.4
12、0 English version Programmable controllers Part 7: Fuzzy control programming (IEC 61131-7:2000) Automates programmables Partie 7: Programmation en logique floue (CEI 61131-7:2000) Speicherprogrammierbare Steuerungen Teil 7: Fuzzy-Control-Programmierung (IEC 61131-7:2000) This European Standard was a
13、pproved by CENELEC on 2000-11-01. CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such n
14、ational standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own lang
15、uage and notified to the Central Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal,
16、Spain, Sweden, Switzerland and United Kingdom.Foreword The text of document 65B/406/FDIS, future edition 1 of IEC 61131-7, prepared by SC 65B, Devices, of IEC TC 65, Industrial-process measurement and control, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61131-7 o
17、n 2000-11-01. The following dates were fixed: latest date by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dop) 2001-08-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2003-11
18、-01 Annexes designated “normative“ are part of the body of the standard. Annexes designated “informative“ are given for information only. In this standard, annex ZA is normative and annexes A, B, C, D and E are informative. Annex ZA has been added by CENELEC. _ Endorsement notice The text of the Int
19、ernational Standard IEC 61131-7:2000 was approved by CENELEC as a European Standard without any modification. _ 2egaP EN611317:2000Page2 EN611317:2000 BSI 04-2001 CONTENTS Page INTRODUCTION 6 Clause 1 Scope and object . 8 2 Normative references. 8 3 Definitions 8 4 Integration into the programmable
20、controller10 5 Fuzzy Control Language FCL 11 5.1 Exchange of fuzzy control programs.11 5.2 Fuzzy Control Language elements12 5.3 FCL example.21 5.4 Production rules and keywords of the Fuzzy Control Language (FCL) .21 6 Compliance.25 6.1 Conformance classes of Fuzzy Control Language FCL .25 6.2 Data
21、 check list .27 Annex A (informative) Theory .29 A.1 Fuzzy Logic.29 A.2 Fuzzy Control33 A.3 Performance of Fuzzy control40 Annex B (informative) Examples.42 B.1 Pre-control42 B.2 Parameter adaptation of conventional PID controllers43 B.3 Direct fuzzy control of a process43 Annex C (informative) Indu
22、strial example Container crane .44 Annex D (informative) Example for using variables in the rule block 54 Annex E (informative) Symbols, abbreviations and synonyms56 Annex ZA (normative) Normative references to international publications with their corresponding European publications 57 Figure 1 Exa
23、mple of a fuzzy control Function Block in FBD representation 11 Figure 2 Data exchange of Programs in Fuzzy Control Language (FCL) 12 Figure 3 Example of a Function Block interface declaration in ST and FBD languages.13 Figure 4 Example of ramp terms.14 Figure 5 Example of usage of variables for mem
24、bership functions.14 Figure 6 Example of singleton terms.15 Figure 7 Example for fuzzy function block .21 Figure 8 Levels of conformance25 3egaP EN611317:2001Page3 EN611317:2000 BSI 04-2001 Figure A.1 Membership functions of the terms “full legal age“ and “adult“30 Figure A.2 Description of the ling
25、uistic variable “Age“ by linguistic terms and their hierarchy on the time scale (age in years) .30 Figure A.3 Commonly used shapes of membership functions 31 Figure A.4 Algorithms for implementing operations between two membership functions.33 Figure A.5 Structure and functional elements of fuzzy co
26、ntrol34 Figure A.6 The principle of fuzzification (as an example).34 Figure A.7 Representation of the knowledge base in linguistic form.35 Figure A.8 Matrix representation of two variables 35 Figure A.9 Elements of inference36 Figure A.10a An example showing the principles of aggregation37 Figure A.
27、10b The principles of activation (as an example).37 Figure A.10c The principles of accumulation (as an example) .38 Figure A.11a Methods of defuzzification38 Figure A.11b Difference between Left Most Maximum and Right Most Maximum .39 Figure A.11c Difference between Centre of Area and Centre of Grav
28、ity .39 Figure A.11d Methods of defuzzification40 Figure A.12 Examples of fuzzy control characteristic curves41 Figure A.13a Fuzzy-based controller: Fundamental structure.41 Figure A.13b Example of a Fuzzy-based controller41 Figure B.1 Example of a pre-control42 Figure B.2 Example of a parameter ada
29、ptation43 Figure B.3 Example of a direct fuzzy control43 Figure C.1 Industrial example Container crane.44 Figure C.2 Linguistic variable “Distance“ between crane head and target position45 Figure C.3 Linguistic variable “Angle“ of the container to the crane head.45 Figure C.4 Linguistic variable “Po
30、wer“.45 Figure C.5 Rule base46 Figure C.6 Fuzzification of the linguistic variable “distance“.46 Figure C.7 Fuzzification of the linguistic variable “angle“ .47 Figure C.8 Subset of three rules .47 Figure C.9 Elements of aggregation47 Figure C.10 Principles of aggregation .48 Figure C.11 Elements of
31、 activation48 Figure C.12 Principles of activation.49 Figure C.13 Elements of accumulation49 Figure C.14 Principles of accumulation .50 Figure C.15 Defuzzification.51 Figure C.16 Example in SCL.52 Figure D.1 Principle of the controlled system 54 4egaP EN611317:2001Page4 EN611317:2000 BSI 04-2001 Fig
32、ure D.2 Principle of the fuzzy based control of the oven54 Figure D.3 Rule block .54 Figure D.4 Example in FCL.55 Table 1 Defuzzification methods .15 Table 2 Formulae for defuzzification methods .16 Table 3 Paired algorithms.17 Table 4 Activation methods.17 Table 5 Accumulation methods .18 Table 6 P
33、riority of operators18 Table 7 Reserved keywords for FCL .24 Table 8 FCL Basic Level language elements (mandatory) .26 Table 9 FCL Extension Level language elements (optional).27 Table 10 Examples of a list with Open Level language elements .27 Table 11 Data check list .28 Table A.1 Inference steps
34、and commonly used algorithms 37 Table C.1 Inference steps and assigned operator46 Table E.1 Symbols and abbreviations .56 Table E.2 Synonyms.56 5egaP EN611317:2001Page5 EN611317:2000 BSI 04-2001 INTRODUCTION The theory of fuzzy logic in the application of control is named fuzzy control. Fuzzy contro
35、l is emerging as a technology that can enhance the capabilities of industrial automation, and is suitable for control level tasks generally performed in Programmable Controllers (PC). Fuzzy control is based upon practical application knowledge represented by so-called linguistic rule bases, rather t
36、han by analytical (either empirical or theoretical) models. Fuzzy control can be used when there is an expertise that can be expressed in its formalism. That allows to take available knowledge to improve processes and perform a variety of tasks, for instance control (closed or open loop, single or m
37、ulti-variable, for linear or non-linear systems), on-line or off-line setting of control systems parameters, classification and pattern recognition, real-time decision making (send this product to machine A or B ?), helping operators to make decisions or tune parameters, detection and diagnosis of f
38、aults in systems. Its wide range of applications and natural approach based on human experience makes fuzzy control a basic tool that should be made available to programmable controller users as a standard. Fuzzy control can also, in a straightforward way, be combined with classical control methods.
39、 The application of fuzzy control can be of advantage in such cases where there is no explicit process model available, or in which the analytical model is too difficult to evaluate or when the model is too complicated to evaluate in real time. Another advantageous feature of fuzzy control is that h
40、uman experience can be incorporated in a straightforward way. Also, it is not necessary to model the whole controller with fuzzy control: sometimes fuzzy control just interpolates between a series of locally linear models, or dynamically adapts the parameters of a “linear controller“, thereby render
41、ing it non-linear, or alternatively just “zoom in“ onto a certain feature of an existing controller that needs to be improved. Fuzzy control is a multi-valued control, no longer restricting the values of a control proposition to “true“ or “false“. This makes fuzzy control particularly useful to mode
42、l empirical expertise, stating which control actions have to be taken under a given set of inputs. The existing theory and systems already realized in the area of fuzzy control differ widely in terms of terminology (definitions), features (functionalities) and implementation (tools). Fuzzy control i
43、s used from small and simple applications up to highly sophisticated and complex projects. To cover all kinds of usage in this part of IEC 61131, the features of a compliant fuzzy control system are mapped into defined conformance classes. The basic class defines a minimum set of features which has
44、to be achieved by all compliant systems. This facilitates the exchange of fuzzy control programs. 6egaP EN611317:2001Page6 EN611317:2000 BSI 04-2001 Optional standard features are defined in the extension class. Fuzzy control programs applying these features can only be fully ported among systems us
45、ing the same set of features, otherwise a partial exchange may be possible only. This standard does not force all compliant systems to realize all features in the extension class, but it supports the possibility of (partial) portability and the avoidance of the usage of non-standard features. Theref
46、ore, a compliant system should not offer non-standard features which can be meaningfully realized by using standard features of the basic class and the extension class. In order not to exclude systems using their own highly sophisticated features from complying with this part of IEC 61131 and not to
47、 hinder the progress of future development, this standard permits also additional non-standard features which are not covered by the basic class and the extension class. However, these features need to be listed in a standard way to ensure that they are easily recognised as non-standard features. Th
48、e portability of fuzzy control applications depends on the different programming systems and also the charcteristics of the control systems. These dependencies are covered by the data check list to be delivered by the manufacturer. 7egaP EN611317:2001Page7 EN611317:2000 BSI 04-2001 PROGRAMMABLE CONT
49、ROLLERS Part 7: Fuzzy control programming 1 Scope and object This part of IEC 61131 defines a language for the programming of Fuzzy Control applications used by programmable controllers. The object of this part of IEC 61131 is to offer the manufacturers and the users a well-defined common understanding of the basic means to integrate fuzzy control applications
