BS IEC 61334-1-4-1998 Distribution automation using distribution line carrier systems - General considerations - Guide to identification of data transmission parameters concerning .pdf

1、BRITISH STANDARD BS IEC 61334-1-4:1995 Distribution automation using distribution line carrier systems Part 1: General considerations Section 4: Guide to identification of data transmission parameters concerning medium and low-voltage distribution mains ICS 29.240.20; 33.040.40; 35.200BSIEC 61334-1-

2、4:1995 This British Standard, having been prepared under the directionof the Electrotechnical Sector Board, was published underthe authority of the Standards Board and comes intoeffect on 15 May 1998 BSI 03-1999 ISBN 0 580 28599 5 National foreword This British Standard reproduces verbatim IEC 61334

3、-1-4:1995 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee PEL/57, Power system control and associated communications, which has the responsibility to: aid enquirers to understand the text; present to the responsible internat

4、ional/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 represented on this committee can be obtained on request to its se

5、cretary. 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 the other, publications may contain identifiers from both systems. Cro

6、ss-references The British Standards which implement international or European publications referred to in this document 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 Electron

7、ic Catalogue. A British Standard does not purport to include 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 docum

8、ent comprises a front cover, an inside front cover, pages i and ii, theCEIIEC title page, pages ii to iv, pages 1 to 23 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front co

9、ver. Amendments issued since publication Amd. No. Date CommentsBSIEC 61334-1-4:1995 BSI 03-1999 i Contents Page National foreword Inside front cover Foreword iv Text of CEI IEC 1334-1-4 5ii blankBSIEC 61334-1-4:1995 ii BSI 03-1999 Contents Page Foreword iv 1 Scope 1 2 Transmission parameters 1 3 Tra

10、nsmission parameters of the main components of a distribution network 2 3.1 Capacitors 2 3.2 Transformers 2 3.3 Cables 3 4 Section of an MV power network 3 5 Section of an LV power network 3 Figure 1 Examples of impedance versus frequency of typical MV and LV capacitor banks 5 Figure 2a Examples of

11、impedance versus frequency of a typical MV/LV transformer (MV side) 6 Figure 2b Example of transfer function of typical MV/LV transformer: signal injection at MV side (phase-to-ground); signal measurement at LV side (phase-to-neutral) 7 Figure 2c Example of transfer function of a typical MV/LV trans

12、former: signal injection at MV side (phase-to-neutral); signal measurement at LV side (phase-to-ground) 8 Figure 3a Example of coupling point impedance versus frequency in an MV/LV substation at the midpoint of an MV overhead line (phase-to-ground coupling) 9 Figure 3b Example of coupling point impe

13、dance versus frequency in an MV/LV substation connected to the overhead line through a cable (phase-to-ground coupling) 10 Figure 4a Examples of attenuation versus frequency of an MV network (underground cables) 11 Figure 4b Examples of attenuation versus distance of an MV network (underground cable

14、s) 12 Figure 4c Examples of attenuation versus distance of an MV cable connecting six MV/LV substations Transmission from each substation and measurements at the others (phase-to-ground coupling) 13 Figure 5a Examples of noise level versus frequency on an MV network (underground cables) 14 Figure 5b

15、 Examples of noise levels measured in six MV/LV substations connected to an MV overhead line (phase-to-ground coupling 15 Figure 6a Example of coupling point impedance versus frequency of an LV underground cable network (phase-to-neutral coupling) 16 Figure 6b Examples of coupling point impedance ve

16、rsus frequency of an LV overhead line network (phase-to-neutral coupling) 17 Figure 7 Examples of attenuation versus frequency of an LV underground cable with a length up to 500 m (phase-to-neutral coupling) 18BSIEC 61334-1-4:1995 BSI 03-1999 iii Page Figure 8 Example of attenuation versus time of d

17、ay of an LV underground cable with a length up to 500 m (phase-to-neutral coupling) 19 Figure 9 Examples of attenuation versus distance of an LV overhead line (phase-to-neutral coupling) 20 Figure 10 Example of attenuation of an LV cable at different floors of a building (signal injection, ground fl

18、oor 21 Figure 11a Example of noise level versus frequency on an LV overhead line network (phase-to-neutral coupling) 22 Figure 11b Example of noise level distribution probability on an LV overhead line network (signal frequency = 80 KHz, phase-to-neutral coupling) 23BSIEC 61334-1-4:1995 iv BSI 03-19

19、99 Foreword 1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization

20、 in the electrical and electronic fields. To this end and in addition to other activities, the IEC publishes International Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. Inte

21、rnational, governmental and non-governmental organizations liaising with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) Th

22、e formal decisions or agreements of the IEC on technical matters, express as nearly as possible, an international consensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees. 3) The documents produced have the form of recomm

23、endations for international use and are published in the form of standards, technical reports or guides and they are accepted by the National Committees in that sense. 4) In order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparent

24、ly to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard and the corresponding national or regional standard shall be clearly indicated in the latter. 5) The IEC provides no marking procedure to indicate its approval and cannot be rendered r

25、esponsible for any equipment declared to be in conformity with one of its standards. 6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

26、 The main task of IEC technical committees is to prepare International Standards. In exceptional circumstances, a technical committee may propose the publication of a technical report of one of the following types: type 1, when the required support cannot be obtained for the publication of an Intern

27、ational Standard, despite repeated efforts; type 2, when the subject is still under technical development or where for any other reason there is the future but not immediate possibility of an agreement on an International Standard; type 3, when a technical committee has collected data of a different

28、 kind from that which is normally published as an International Standard, for example “state of the art”. Technical reports of types 1 and 2 are subject to review within three years of publication to decide whether they can be transformed into International Standards. Technical reports of type 3 do

29、not necessarily have to be reviewed until the data they provide are considered to be no longer valid or useful. IEC 1334-1-4, which is a technical report of type 3, has been prepared by IEC technical committee 57: Power system control and associated communications. The text of this technical report

30、is based on the following documents: Full information on the voting for the approval of this technical report can be found in the report on voting indicated in the above table. This report is a Technical Report of type 3 and is of a purely informative nature. It is not to be regarded as an Internati

31、onal Standard. Committee draft Report on voting 57(SEC)197 57/241/RVCBSIEC 61334-1-4:1995 BSI 03-1999 1 1 Scope This Technical report (type 3) summarizes the results obtained through an intense activity of research carried out in some European countries, in order to assess the ability of MV (medium

32、voltage) and LV (low voltage) distribution power networks to be used as a data transmission medium suitable to support applications related to distribution automation systems. Taking into account that the research has been focused on a reduced number of typical situations, the results, shown in this

33、 report, will be considered representative of all the situations similar to those that have been investigated. The results are expressed with reference to certain transmission parameters, described in clause 2, which are of great importance for the design of a distribution line carrier communication

34、 system. 2 Transmission parameters Medium and low voltage, power lines, conceived to carry high power at a 50 Hz or 60 Hz frequency, provide a difficult channel for data communication. Signal attenuation and noise level influenced by the electrical loads and by changes in the network topology lead t

35、o a great variation in transmission quality as a function of frequency, time and location. Moreover, a distribution power line cannot be assumed as a homogeneous medium for communication purposes because of the serious impedance mismatch occurring, for instance, at the transition points between cabl

36、es and overhead lines and at branch-off points. This causes signal reflection and consequently a supplementary attenuation and phase distortion of the transmission signal. Nevertheless, even though the channel characteristics are so unpredictable (varying with time and location), the investigatory w

37、ork carried out on several distribution networks provides sufficient information which is useful for determining cost efficient methods to overcome the basic difficulties. First of all, the behaviour of single network components (e.g. power transformers, capacitor banks, cables, overhead lines, volt

38、age and current transformers, etc.) when transmission signals pass through them, is well known. The resulting characteristics of each component can be identified by: its impedance as a function of frequency, Z(f); its transfer function as a function of frequency, H(f). NOTEThe module is the ratio of

39、 received signal amplitude to transmitted signal amplitude and the phase is the difference between the received signal phase and the transmitted signal phase. Available information refers to transmission characteristics of a section of distribution network between two coupling points, e.g. the point

40、s where transmission signals are transmitted/received. There are two cases to be considered when two coupling points are, from a transmission point of view, either interconnected or disconnected. The first case happens when there is a galvanic continuity between the two coupling points or if transmi

41、ssion continuity is ensured by means of an appropriate devices such as a by-pass. The second case happens when neither galvanic nor transmission continuity exists. With reference to two interconnected coupling points, the parameters assumed to identify the characteristics of the corresponding transm

42、ission channel are: the impedance, as a function of frequency and time, related to each coupling point Z C(f,t) the transmission transfer function, as a function of frequency and time, between the two considered coupling points, H C(f,t) NOTEThe module is the ratio of received signal amplitude to tr

43、ansmitted signal amplitude and the phase is the difference between the received signal phase and the transmitted signal phase. the noise, as a function of frequency and time, related to each coupling point N C(f,t) With reference to two disconnected coupling points, the most important transmission p

44、arameter is: the cross-talk transfer function, as a function of frequency and time, between the two considered coupling points C C(f,t) NOTEThe module is the ratio of received signal amplitude to transmitted signal amplitude and the phase is the difference between the received signal phase and the t

45、ransmitted signal phase. The above mentioned parameters allow the evaluation of the expected channel characteristics by the creation of a mathematical model approximating the real channel.BSIEC 61334-1-4:1995 2 BSI 03-1999 3 Transmission parameters of the main components of a distribution network 3.

46、1 Capacitors MV capacitor banks, for reactive power compensation, installed in HV/MV or MV/LV substations present (Figure 1, curve “a”) a very high selective behaviour with a resonance frequency of about50kHz and a very low corresponding impedance (about 0,017). This means that the impedance rapidly

47、 increases when the frequency of the transmission signal is far from the resonance point. Curve “b” shows the typical behaviour of the same MV capacitor banks provided with external electrical connections of longer length (about1,5m). It can be noticed that the resonance point falls to about30kHz, t

48、hus significantly modifying the impedance values as a function of the frequency. In practice, since the external electrical connections are normally longer than1,5m, the corresponding shifting of the resonance point towards frequencies less than30kHz allows using frequencies greater than50kHz, so th

49、at MV capacitor banks do not involve a significant sink of the transmission signals. This means that in the frequency range above50kHz, it is not necessary to add line traps to the MV capacitor banks for transmission purposes. As far as the LV capacitors are concerned, the situation is quite similar and the previous conclusion can be drawn. The curve “c” shows the typical behaviour of an LV capacitor with very short external electrical connections, whilst the curve “d” refers to the same LV capacitor with external co