1、 STD-BSI BS EN bZbb0-2-ENGL L777 Lb24bb9 b48348 Tbb BRITISH STANDARD Short-circuit currents in DC auxiliary installations in power plants and substations Part 2. Calculation of effects The European Standard EN 61660-2 : 1997 has the status of a British Standard ICs 29.240.01 3s EN i1660-2 : 1997 EC
2、61660-2 1997 BS EN 61660-2 1997 Amd. No. Date National foreword Text affected This British standard is the English language version of EN 61660-2 : 1997. It is identical with IEC 61660-2 : 1997. The UK participation in its preparation was entrusted to Technical Committee PEy73, Short-circuit current
3、s, which has the responsibility to: - aid enquirers to understand the text; - present to the responsible internationalEuropean committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; - monitor related international and European developments and pro
4、mulgate them in the UIC A list of organizations represented on this committee 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 t
5、he change over from one numbering system to 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 correspond
6、ing or European publications. The British Standards 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 Compliance with a British Standard does not of itself
7、confer immunity from legal obligations. facility of the BSI Standards Electronic Catalogue. This British Standard, having been prepared under the direction of the Electrotechnical Sector Board, was published under the authority of the Standards Board and comes into effect on 15 October 1997 O BSI 19
8、97 ISBN O 580 28630 8 STD-BSI BS EN bLbb-2-ENGL L797 Lb24bb7 b48350 bL4 E EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 61660-2 July 1997 ICC 29.240.01 Descriptors: Short-circuit current. auxiliary installations, power plants, substation, calculation of effects English version Short-circuit c
9、urrents in d.c. auxiliary installations in power plants and substations Part 2: Calculation of effects (IEC 61 660-21997) Courants de court-circuit dans les Kutschlustrme in installations auxiliaires alimentes Gleichstrom-Eigenbedarfsanlagen en courant continu dans les centrales in Kraftwerken und S
10、chaltanlagen et les postes Teil 2: Berechnung der Wirkungen Partie 2: Calcul des effets (CE1 61 660-2:1997) (IEC 61 660-2: 1 997) This European Standard was approved by CENELEC on 1997-07-01. CENELEC members are bound to comply with the CENICENELEC Internal Regulations which stipulate the conditions
11、 for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Central Secretariat or to any CENELEC member. This European Standard exists in three o
12、fficial versions (English, french, German). A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to the Centrai Secretariat has the same status as the official versions. CENELEC members are the national electrotechnical c
13、ommittees of Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CENELEC European Committee for Electrotechnicai Standardization Comit Europen de Normalisation Electrotechnique
14、 Europisches Komitee fr Elektrotechnische Normung Centrai Secretariat: rue de Stassart 35, B - 1050 Brussels 1997 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 61 660-2:1997 E STD-BSI BS EN bLbbU-2-ENGL 1997 D Lb24bb9 Ub48ilC;L
15、550 m Page 2 EN 61660-2 : 1997 Foreword The text of document 73/85/FDIS, future edition 1 of IEC 61660-2, prepared by IEC TC 73, Short-circuit currents, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61 660-2 on 1997-07-01. The following dates were fixed: - latest d
16、ate by which the EN has to be implemented at national level by publication of an identical national standard or by endorsement (dopl 1 998-04-0 1 - latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 1998-04-01 Annexes designated “normative“ are part of the
17、 body of the standard. Annexes designated “informative“ are given for information only. In this standard, annex ZA is normative and annexes A and B are informative. Annex ZA has been added by CENELEC. Endorsement notice The text of the International Standard IEC 61 660-2: 1997 was approved by CENELE
18、C as a European Standard without any modification. . .L STD-BSI BS EN bLbbO-2-ENGL 1777 U Lb24bb9 Ob48352 497 Page 3 EN 61660-2 : 1997 CONTENTS Clause 1 General 1.1 Scope 1.2 Normative references . 1.3 Symbols and units 1.4 Definitions . Electromagnetic effect on rigid conductors 2.1 General . 2.2 C
19、alculation of electromagnetic forces . 2.3 Calculation of stresses in rigid conductors and forces on supports . 2.4 Design load for post insulators, their supports and connectors 3.1 General . 3.2 Calculation of temperature rise 2 3 Thermal effect on bare conductors and electrical equipment . Tables
20、 . Figures . Ann exes A B Bibliography ZA (normative) Normative references to international publications with their Equations for calculations of diagrams Page 4 4 5 5 8 9 9 10 11 17 17 17 18 20 24 34 38 corresponding European publications 39 O BSI 1997 STD-BSI BS EN blbb-2-ENGL 1797 D Lb24bb7 Ob483
21、53 323 I Page 4 EN 61660-2 : 1997 SHORT-CIRCUIT CURRENTS IN DC AUXILIARY INSTALLATIONS IN POWER PLANTS AND SUBSTATIONS - Part 2: Calculation of effects 1 General 1.1 Scope This part of IEC 61660describes a method for calculation of the mechanical and thermal effects on rigid conductors caused by sho
22、rt-circuit currents in d.c. auxiliary installations in power plants and substations. Such systems may contain the following items of equipment which act as sources, as well as contributing to the short-circuit currents: - rectifiers in three-phase a.c. bridge connection for 50 Hz; - stationary lead-
23、acid batteries; - smoothing capacitors; - d.c. motors with independent excitation. This standard provides a method which has wide application, and which gives results of sufficient accuracy. The calculation method is based on substitute functions, which cause approximately the same maximum stresses
24、in the conductors and the same forces on the supports as the actual electromagnetic force. The standardized calculation procedures of clauses 2 and 3 are applicable for the electromagnetic effect on rigid conductors and the thermal effect on bare conductors and electrical equipment, respectively. Fo
25、r cables and insulated conductors, however, reference is made to IEC 60949 and IEC 60986, for example. Only d.c. auxiliary installations in power plants and substations are dealt with in this standard. In particular, the following points should be noted: - The calculation of short-circuit currents s
26、hould be based on IEC 61660-1. - Short-circuit duration used in this standard depends on the protection concept, and should be considered in that sense. - These standardized procedures are adjusted to practical requirements, and contain simplifications with safety margins. Testing or more detailed m
27、ethods of calculation or both may be used. - In clause 2 of this standard, only the stresses caused by short-circuit currents are calculated. Furthermore, other stresses can exist, such as those caused by dead-load, operating forces, or earthquakes. The combination of these loads with the short-circ
28、uit loading should be part of an agreement and/or given by standards, for example erection codes. STD-BSI BS EN bLbb0-2-ENGL 1977 W lb24bb7 Ob118354 2bT aP Page 6 EN 61660-2 : 1997 1.2 Normative references The following normative documents contain provisions which, through reference in this text con
29、stitute provisions of this part of IEC 61660. At the time of publication, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this part of IEC 61660 are encouraged to investigate the possibility of applying the most recent editions o
30、f the normative documents indicated below. Members of IEC and IS0 maintain registers of currently valid International Standards. IEC 60865-1: 1993, Short-circuit currents - Calculation of effects - Part 1: Definitions and calculation methods IEC 60865-2: 1994, Short-circuit currents - Calculation of
31、 effects - Part 2: Examples of calculation IEC 60949: 1 988, Calculation of thermally permissible short-circuit currents, taking into account non-adiabatic heating effects IEC 60986: 1989, Guide to the short-circuit temperature limits of electric cables with a rated voltage from 1,8/3 (3,s) kV to 18
32、/30 (36) kV IEC 61 660-1 : 1997, Short-circuit currents in d.c. auxiliary installations in power plants and substations - Part 1: Calculation of short-circuit currents 1.3 Symbols and units All equations used in this standard are quantity equations in which quantity symbols represent physical quanti
33、ties possessing both numerical values and dimensions. The symbols used in this standard and their exemplary SI units are given in the following lists. 1.3.1 Symbols for clause 2: electromagnetic effects Impulse for determining the parameters of the substitute rectangular function A2s Ai AS Cross-sec
34、tion of one subconductor m2 a Centre line distance between conductors m am Effective distance between neighbouring main conductors m as Effective distance between subconductors m a1 n Centre line distance between subconductor 1 and subconductor n m a1 a Centre line distance between subconductors m b
35、 Dimension of a subconductor perpendicular to the direction of the force m bm Dimension of a main conductor perpendicular to the direction of the force m C Factor for the influence of connecting pieces 1 D Outer diameter of tubular conductor m d m Dimension of a subconductor in the direction of the
36、force STD-BSI BS EN bLbb0-2-ENGL L997 lb24bb7 ab48355 LTb W Page 6 EN 61660-2 : 1997 Dimension of a main conductor in the direction of the force Youngs modulus Force acting between two, parallel, long conductors during a short circuit Force between main conductors caused by the substitute rectangula
37、r function Force between subconductors caused by the substitute rectangular function Force on support (peak value) Force between main conductors during a short circuit (peak value) Force between subconductors during a short circuit Relevant natural frequency of a main conductor Relevant natural freq
38、uency of a subconductor Value of acceleration of gravity Value for determining of the parameters of the substitute rectangular function Current of the substitute rectangular function for the calculation of the force between main conductors Current of the substitute rectangular function for the calcu
39、lation of the force between subconductors Quasi steady-state short-circuit current Peak short-circuit current Instantaneous values of current in conductors in the sections of the standard approximation function Instantaneous values of currents in the conductors L1 and L2 Second moment of main conduc
40、tor area Second moment of subconductor area Number of sets of spacers or stiffening elements Factor for effective conductor distance between subconductor 1 and subconductor n Factor for effective conductor distance Centre line distance between supports Centre line distance between connecting pieces
41、Mass per unit length of main conductor Mass per unit length of subconductor Total mass of one set of connecting pieces Factors for determining the parameters of the substitute rectangular function Number of subconductors of a main conductor Ratio /dip Factor of plasticity Stress corresponding to the
42、 yield point Wall thickness of tubes m N/m2 N N N N N N Hz Hz m/s2 A2s3 A A A A A A m4 m4 1 1 1 m m kgim kgim kg 1 1 1 1 N/m2 m STD-BSI BS EN bLbbO-2-ENGL I997 m lb24bb9 Ob4835b 032 U Page 7 EN 61660-2 : 1997 Tk Short-circuit duration S Tme Vibration period of the main conductor S Tmes Vibration per
43、iod of the subconductor S P Time to peak S FI Time of substitute rectangular function for the calculation of the force tRS Time of the substitute rectangular function for the calculation of the force VF Ratio of dynamic and static force on supports 1 V*S Ratio of dynamic and static subconductor stre
44、ss 1 Z Section modulus of main conductor m3 =s Section modulus of subconductor m3 a Factor for force on support 1 Factor for main conductor stress 1 Y Factor for relevant natural frequency estimation 1 S between main conductors between subconductors S VtJ Ratio of dynamic and static main conductor s
45、tress 1 PO Magnetic constant, permeability of vacuum H/m om N/m2 =fi Bending stress caused by the forces between subconductors N/m2 Bending stress caused by the forces between main conductors =tot Resulting conductor stress 51 Rise-time constant N/m2 S 22 Decay-time constant S 1.3.2 Symbols for clau
46、se 3: Thermal effects A Ai t h Ithr K t h Sthr Tk Tkr P b Main conductor cross-section Impulse for determining of the parameters of the substitute rectangular function Thermal equivalent short-time current (r.m.s.) Rated short-time withstand current (r.m.s.) Factor for calculating Sthr Thermal equiv
47、alent short-time current density (r.m.s.) Rated short-time withstand current density (r.m.s.) Short-circuit duration Rated short-time Time to peak Conductor temperature at the beginning of the short circuit Conductor temperature at the end of the short circuit m2 A2s S S S “C “C STD-BSI BS EN bLbbO-
48、2-ENGL 1997 E Lb24bb7 0646357 T77 M Page 8 EN 61660-2 : 1997 1.4 Definitions For the purpose of this part of IEC 61660, the following definitions apply. 1.4.1 Definitions for clause 2: electromagnetic effects 1.4.1.1 main conductor: A conductor, or an arrangement composed of a number of conductors,
49、which carries the total current. 1.4.1.2 subconductor: A single conductor which carries a certain part of the total current and is a part of the main conductor. 1.4.1.3 fixed support: A support of a conductor which does not permit the conductor to move angularly at the point of the support. 1.4.1.4 simple support: A support of a conductor which permits angular movement at the point of support. 1.4.1.5 connecting piece: Any additional mass within a span which does not belong to the uniform conductor material. This includes among other
