1、BRITISH STANDARD BS EN 50299:2002 Incorporating Corrigendum No. 1 Oil-immersed cable connection assemblies for transformers and reactors having highest voltage for equipment U mfrom 72,5 kV to 550 kV The European Standard EN 50299:2002 has the status of a British Standard ICS 29.180 BS EN 50299:2002
2、 This British Standard, having been prepared under the direction of the Electrotechnical Sector Policy and Strategy Committee, was published under the authority of the Standards Policy and Strategy Committee on 19 November 2002 BSI 25 January 2005 ISBN 0 580 40795 0 National foreword This British St
3、andard is the official English language version of EN 50299:2002, including Corrigendum April 2004. The UK participation in its preparation was entrusted to Technical Committee PEL/14, Power transformers, which has the responsibility to: A list of organizations represented on this committee can be o
4、btained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facili
5、ty of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations.
6、 aid enquirers 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. Summary of pages
7、 This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 11 and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments 15517 Corrigendum No. 1 25 Janua
8、ry 2005 Figure 2 replacement of column U maxwith ?UEUROPEAN STANDARD EN 50299 NORME EUROPENNE EUROPISCHE NORM November 2002 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secreta
9、riat: rue de Stassart 35, B - 1050 Brussels 2002 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 50299:2002 E ICS 29.180 Incorporating Corrigendum April 2004 English version Oil-immersed cable connection assemblies for transformer
10、s and reactors having highest voltage for equipment U mfrom 72,5 kV to 550 kV Bote de raccordement de cble pour transformateurs immergs et bobine dinductance de tensions comprises entre 72,5 kV et 550 kV lgefllte Kabelanschlusseinheiten fr Transformatoren und Drosselspulen mit einer hchsten Spannung
11、 fr Betriebsmittel U mvon 72,5 kV bis 550 kV This European Standard was approved by CENELEC on 2002-10-01. 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 alte
12、ration. 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 official versions (English, French, German). A version in any other language made by t
13、ranslation under the responsibility of a CENELEC member into its own language 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, Gre
14、ece, Hungary, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Slovakia, Spain, Sweden, Switzerland and United Kingdom. EN 50299:2002 2 Foreword This European Standard was prepared by the CENELEC Technical Committee TC 14, Power transformers. The text of the draft was submi
15、tted to the formal vote and was approved by CENELEC as EN 50299 on 2002-10-01. 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) 2003-10-01 - latest date by which the national
16、 standards conflicting with the EN have to be withdrawn (dow) 2005-10-01 _ 3 EN 50299:2002 Contents 1 Scope.4 2 Normative references4 3 Definitions.5 4 Limits of supply. 6 5 Rated values6 6 Preferred values6 6.1 Highest voltage for equipment 6 6.2 Rated current6 7 Requirements.6 7.1 Temperature of c
17、onnection interface 6 7.2 Mechanical requirements . 7 7.3 Standard dimensions . 7 7.4 Disconnecting link 7 7.5 Protection against corrosion. 7 7.6 Mechanical forces on cable terminations 8 8 Tests 8 8.1 Factory tests.8 8.2 Tests after installation 8 Figure 1 Limits of supply for transformer end term
18、inal and cable termination.10 Figure 2 Standard dimensions for cable connection assembly.11 EN 50299:2002 4 1 Scope This standard covers the oil-immersed single-phase connection assembly of cables for transformers and reactors, designed in accordance with EN 60076 series and with EN 60289, respectiv
19、ely. NOTE In the standard the term “transformer“ is used as common definition for transformer and reactor. The purpose of EN 50299 is to establish for the cable assemblies: the electrical and mechanical requirements, including interchangeability; the limits of supply; the test to be carried out. It
20、complements and amends, if necessary, the relevant IEC standards and applies to oil immersed cable connections, suitable for fluid-filled or dry-type cable terminations. EN 50299 does not cover direct cable terminations (see 3.3.3), but, in this case, upon agreement between purchaser and supplier, t
21、he standard may be used for guidance except for Figure 1 and Figure 2 which are not applicable. This standard applies to oil-immersed cable connection boxes on transformers with highest voltage for equipment U m= 72,5 kV to 550 kV, including the current conductor terminal at the cable sealing end of
22、 the transformer. 2 Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amen
23、dments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 60076 Series Power transformers (IEC 60076 series, mo
24、d.) EN 60289 Reactors (IEC 60289, mod.) IEC 60141 Series Test on oil-filled and gas-pressure cables and their accessories IEC 60296 Specification for unused mineral insulating oils for transformers and switchgear IEC 60840 Power cables with extruded insulation and their accessories for rated voltage
25、s above 30 kV (U m= 36 kV) up to 150 kV (U m= 170 kV) Test methods and requirements IEC/TR2 61639 Direct connection between power transformers and gas-insulated metal-enclosed switchgear for rated voltages of 72,5 kV and above 5 EN 50299:2002 3 Definitions For the purposes of this European Standard
26、the following definitions apply. 3.1 cable-connection assembly combination of a cable termination and a cable connection box which mechanically and electrically connects the cable to the transformer 3.2 cable connection box part of the transformer which houses the cable termination and the interface
27、 to the transformer connection 3.3 cable termination equipment fitted to the end of a cable to ensure electrical connection with other parts of the system and to maintain the insulation up to the point of connection 3.3.1 fluid-filled cable termination cable termination which includes an insulating
28、fluid as part of the cable connection assembly and comprises a segregation between said cable fluid in the cable connection box 3.3.2 dry-type cable termination cable termination which comprises an elastomeric electrical stress control component in intimate contact with a separating insulating barri
29、er between the cable insulation and the insulation of the cable connection box. The cable termination does not require any insulating fluid 3.3.3 direct cable termination cable termination directly fitted on the end of the cable without any separating insulating barrier between the cable insulation
30、and the insulation of the cable connection box. The cable enters directly into the cable box via a gland 3.4 disconnect chamber cable connection box which has an oil/oil bushing fitted between the box and the main transformer tank, in such a manner as to prevent, in service conditions, direct commun
31、ication of oil in the main tank with the fluid in cable connection box. It is fitted with a disconnecting link 3.5 disconnecting link removable link inside a disconnect chamber which allows the transformer to be electrically isolated from the cable termination EN 50299:2002 6 4 Limits of supply The
32、limits of supply of transformer and cable termination shall be according to Figure 1. 5 Rated values The following rated values shall apply: a) highest voltage for equipment; b) rated insulation level; c) rated current; d) temperature rise; e) rated short-time and peak withstand currents; f) rated d
33、uration of short-circuit; g) cable commissioning test voltage. 6 Preferred values 6.1 Highest voltage for equipment The highest voltage for equipment U m of the cable connection shall be equal to the values for the cable and the transformer and shall be selected from the following preferred values:
34、72,5 kV - 123 kV - 145 kV - 170 kV - 245 kV - 300 kV - 362 kV - 420 kV - 525 (550) kV 6.2 Rated current The rated current shall be selected from the following preferred values: 400 A 1 000 A 1 600 A 2 000 A The value of 2 000 A cannot be exceeded. 7 Requirements 7.1 Temperature of connection interfa
35、ce The current-carrying contact surfaces of the connection interface shall be either bare copper or copper silver-coated or tin-coated or silver-coated aluminium. The temperature of this interface shall not exceed the limit given in the IEC standard for the cable for which the cable connection box i
36、s designed. 7 EN 50299:2002 NOTE As the maximum conductor temperature for cables is limited by the maximum operating temperature for the insulation, there are certain cable insulations which cannot withstand the maximum temperature specified for the transformer if there is heat transfer across the c
37、onnection interface of the cable termination. For cases when the temperature limit given by the IEC standard cannot be achieved, the supplier of the transformer should provide data on temperature rise of the main circuit end terminal and the insulating liquid as function of current. 7.2 Mechanical r
38、equirements The cable connection box shall be oil-tight and with the same degree of vacuum tightness as the transformer. It shall be filled with degassed oil, normally under vacuum conditions. However, if the transformer tank is not designed to withstand a vacuum, the oil filling shall be carried ou
39、t under the same conditions as the main transformer tank. The oil used for filling the cable connection box shall comply with the requirements of IEC 60296 when sampled after filling and remaining in the box for a period of 20 min to 30 min. Figure 1 is a sketch of a typical arrangement of a cable t
40、ermination assembly. The cable supplier provides the details inside the dotted line. The transformer supplier provides the other details. See also data list. Figure 1 and Figure 2 show the situation when the cable enters from below. The arrangement can be rotated to allow the cable to enter from abo
41、ve or changed to allow the cable to enter horizontally. 7.3 Standard dimensions Standard dimensions for cable connection boxes, connections from the transformer in the cable connection box and cable terminations are shown in Figure 2. With the given five sizes, the voltage range U m from 72,5 kV to
42、550 kV is covered. NOTE Design limitations for extruded cables with large conductors or insulation diameters in the 170 kV range, may prevent conformance with this standard. Standard dimensions for the flange of the complete cable connection box towards the transformer tank given in IEC/TR2 61639 ar
43、e preferred. 7.4 Disconnecting link The cable termination may be housed in a disconnect chamber, provided with oil-to-oil bushing to separate the oil in the box from the transformer oil. The purchaser shall specify whether the oil-to-oil bushing is required, or whether the transformer and the cable
44、end sealing with the connection details shall be enclosed in one whole common volume of oil. The purchaser shall also specify whether the oil in the cable connection box is to be connected to a separate conservator. 7.5 Protection against corrosion The cable connection box shall have the same degree
45、 of protection against corrosion as the associated transformer tank. EN 50299:2002 8 7.6 Mechanical forces on cable terminations The cable termination shall be able to withstand a static mechanical force of 2 kN applied transversely to its interface point. NOTE Forces and movements from the transfor
46、mer can be experienced due to temperature variations and vibrations in service. These forces can act on both transformer and cable termination, and depend largely on transformer layout, termination installation, cable design and methods of mechanical support. The design of any support structure shou
47、ld take into account these forces and movements. It is particularly important that the support for the cable connection box should not be fastened to the clamping flange and/or the cable gland (Figure 1, items 9 and 12). The cable termination shall be capable of withstanding the vacuum conditions, w
48、hen the cable connection box is evacuated as part of the liquid filling process of the transformer. 8 Tests 8.1 Factory tests 8.1.1 Check of dimensions The cable connection boxes shall conform to the dimensions of Figure 2. 8.1.2 Vacuum and pressure tests One complete cable connection box shall be m
49、ounted (with the cable termination replaced by a flange) to demonstrate the same ability to withstand vacuum and pressure as the transformer. These tests may be performed in conjunction with the vacuum and pressure tests on the transformer. 8.1.3 Dielectric tests A provisional air-to-oil bushing shall be fitted on the cable connection box (e.g. to the intermediate chamber) to pass dielectric tests of the transformer, with a connection similar
