1、TECHNICALREPORTIECTR 62140-1First edition2002-10Fossil-fired steam power stations Part 1:Limiting controlsCentrales vapeur consommant des combustibles fossiles Partie 1:Rgulations de limitationReference numberIEC/TR 62140-1:2002(E)LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS L
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8、 Centre:Email:custserviec.chTel:+41 22 919 02 11Fax:+41 22 919 03 00LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TECHNICALREPORTIECTR 62140-1First edition2002-10Fossil-fired steam power stations Part 1:Limiting controlsCentrales vap
9、eur consommant des combustibles fossiles Partie 1:Rgulations de limitationPRICE CODE IEC 2002 Copyright-all rights reservedNo part of this publication may be reproduced or utilized in any form or by any means,electronic ormechanical,including photocopying and microfilm,without permission in writing
10、from the publisher.International Electrotechnical Commission,3,rue de Varemb,PO Box 131,CH-1211 Geneva 20,SwitzerlandTelephone:+41 22 919 02 11 Telefax:+41 22 919 03 00 E-mail:inmailiec.ch Web:www.iec.chXAFor price,see current catalogueCommission Electrotechnique InternationaleInternational Electrot
11、echnical Commission LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.2 TR 62140-1 IEC:2002(E)CONTENTSFOREWORD.5INTRODUCTION.71Scope.82Terms,subscripts and abbreviations.82.1Notations.82.2Subscripts.92.3Abbreviations(also used as subscri
12、pts).93Function of limiting controls.103.1Values to be limited.113.2Functional modules for limiting.114List of limiting controls.11Annex A Upper limiting of steam pressure of steam generators.16A.1Task.16A.2Description of the control structure.17A.3Operating behaviour.18A.4Supplementary information.
13、19Annex B Lower limiting of steam pressure of steam generators.20B.1 Task.20B.2 Description of the control structure.21B.3 Operating behaviour.22B.4 Supplementary information.22Annex C Limiting control of thermal stresses in pressure-bearing components.23C.1Task.23C.2Description of the control struc
14、ture.23C.3Operating behaviour.26Annex D Lower limiting of evaporator flow for once-through boilers.27D.1Task.27D.2Description of the control structure.27D.3Operating behaviour.32Annex E Limiting controls on the feed-water function group.36E.1Task.36E.2Description of the control structure.39E.3Operat
15、ing behaviour.40E.4Further control structures.44LICENSED TO MECON Limited.-RANCHI/BANGALOREFOR INTERNAL USE AT THIS LOCATION ONLY,SUPPLIED BY BOOK SUPPLY BUREAU.TR 62140-1 IEC:2002(E)3 Annex F Lower limiting of furnace thermal output,using as an example direct-firingpulverized coal furnace.46F.1Task
16、.46F.2Description of the control structure.49F.3Operating behaviour.49Annex G Permissible turbine thermal stresses.51G.1Task.51G.2Description of the control systems.51G.3Operating behaviour.53G.4 Supplementary information.53Index.54Figure 1 Change in a controlled variable over time.10Figure A.1 Plant circuit diagram for upper steam pressure limiting control usingbypass devices.16Figure A.2 Pressure characteristics of a conventional power station unit,shown formodified sliding pressure.17Figure A
