BS EN 60664-4-2006 Insulation coordination for equipment within low-voltage systems - Consideration of high-frequency voltage stress《低压系统内设备的绝缘配合 高频电压应力的考虑》.pdf

1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58Part 4: Consideration of high-frequency voltage stressThe European Standard EN 60664-4:2006 has the

2、 status of a British StandardICS 29.080.30Insulation coordination for equipment within low-voltage systems BRITISH STANDARDBS EN 60664-4:2006Incorporating corrigendum no. 1 and corrigendum no. 2BS EN 60664-4:2006This British Standard was published under the authority of the Standards Policy and Stra

3、tegy Committee on 28 April 2006 BSI 2007ISBN 0 580 47169 1Amendments issued since publicationAmd. No. Date Comments16804 Corrigendum No. 129 December 2006 Addition of Annex ZA16921 Corrigendum No. 231 January 2007 Correction to fonts that had corrupted throughout the documentThis publication does no

4、t purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard cannot of itself confer immunity from legal obligations.National forewordThis British Standard was published by BSI. It is the UK implementation of E

5、N 60664-4:2006, incorporating Corrigendum October 2006. It is identical with IEC 60664-4:2005. The UK participation in its preparation was entrusted to Technical Committee GEL/109, Insulation co-ordination for low voltage equipment.A list of organizations represented on this committee can be obtaine

6、d on request to its secretary.EUROPEAN STANDARD EN 60664-4 NORME EUROPENNE EUROPISCHE NORM January 2006 CENELEC European Committee for Electrotechnical Standardization Comit Europen de Normalisation Electrotechnique Europisches Komitee fr Elektrotechnische Normung Central Secretariat: rue de Stassar

7、t 35, B - 1050 Brussels 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members. Ref. No. EN 60664-4:2006 E ICS 29.080.30 English version Insulation coordination for equipment within low-voltage systems Part 4: Consideration of high-frequency vol

8、tage stress (IEC 60664-4:2005) Coordination de lisolement des matriels dans les systmes (rseaux) basse tension Partie 4: Considrations sur les contraintes de tension haute frquence (CEI 60664-4:2005) Isolationskoordination fr elektrische Betriebsmittel in NiederspannungsanlagenTeil 4: Bercksichtigun

9、g von hochfrequenten Spannungsbeanspruchungen (IEC 60664-4:2005) This European Standard was approved by CENELEC on 2005-10-01. 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 stand

10、ard 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 official versions (English, French, German). A version in any othe

11、r language made by translation 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, Cyprus, Czech Republic, Denmark, E

12、stonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Incorporating Corrigendum October 2006Foreword The text of document 109/51/FDIS,

13、 future edition 2 of IEC 60664-4, prepared by IEC TC 109, Insulation co-ordination for low-voltage equipment, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60664-4 on 2005-10-01. This European Standard is to be used in conjunction with EN 60664-1 or EN 60664-5. The

14、 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) 2006-08-01 latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2008-10-01 _ Endorsement

15、 notice The text of the International Standard IEC 60664-4:2005 was approved by CENELEC as a European Standard without any modification. _ EN 60664-4:2006 2 Annex ZA has been added by CENELEC. 3 EN 60664-4:2006 CONTENTS INTRODUCTION.7 1 Scope and object8 2 Normative references .9 3 Terms and definit

16、ions .9 4 Clearances.10 4.1 General conditions.10 4.2 Basic information.10 4.3 Homogeneous and approximately homogeneous fields .10 4.3.1 Conditions for approximately homogeneous field 10 4.3.2 Experimental data of breakdown characteristics10 4.3.3 Dimensioning of clearances for homogeneous and appr

17、oximately homogeneous field conditions 10 4.4 Inhomogeneous fields11 4.4.1 Conditions for inhomogeneous field11 4.4.2 Experimental data of partial discharge and breakdown characteristics.12 4.4.3 Dimensioning of clearances for inhomogeneous field conditions12 5 Creepage distances14 5.1 Experimental

18、data14 5.2 Dimensioning of creepage distances 14 6 Solid insulation.17 6.1 General consideration17 6.2 Influencing factors .17 6.3 Dimensioning of solid insulation .18 7 High-frequency testing19 7.1 Basic requirements19 7.2 Test voltage source .20 7.3 Conditioning 20 7.4 High-frequency breakdown tes

19、t20 7.4.1 Test method.20 7.4.2 Test result .20 7.5 High-frequency partial discharge test .20 7.5.1 General considerations 20 7.5.2 Test method.21 7.5.3 Test equipment 21 7.5.4 Test circuit.21 7.5.5 Required bandwidth of the test circuit.22 7.5.6 Dimensioning of the test circuit.22 7.6 Examples of te

20、st results.23 8 Non sinusoidal voltages23 8.1 General considerations 23 8.2 Periodic impulse voltage 24 8.3 Harmonic analysis .24 8.4 Dimensioning procedure and testing 24 Annex A (informative) Insulation characteristics of clearances at high-frequency voltages .26 A.1 Basic information about the br

21、eakdown of clearances.26 EN 60664-4:2006 4 A.2 Experimental data26 A.2.1 Homogeneous and approximately homogeneous field distribution .26 A.2.2 Inhomogeneous field distribution 29 Annex B (informative) Insulation characteristics of creepage distances at high-frequency voltages .33 B.1 Withstand char

22、acteristics of creepage distances.33 B.2 Experimental conditions.33 B.3 Experimental data34 Annex C (informative) Insulation characteristics of solid insulation at high-frequency voltages .36 C.1 Degradation mechanism of solid insulation.36 C.2 Experimental results 39 Annex D (normative) Testing of

23、insulation at high-frequency voltages .46 D.1 Test voltage source .46 D.2 High-frequency partial discharge test .48 D.2.1 Test equipment 48 D.2.2 Test circuit.50 D.3 Examples of test results.57 Annex E (informative) Insulation stressed with non-sinusoidal high-frequency voltages .60 E.1 Objective.60

24、 E.2 Harmonic analysis .60 Annex F (informative) Dimensioning diagrams 65 Annex ZA (normative) Normative references to international publications with theircorresponding European publications.69 5 EN 60664-4:2006 Figure 1 Dimensioning of inhomogeneous clearances in air at atmospheric pressure (point

25、-plane-electrodes, 5 m radius) to avoid PD (clearance 1 mm) or breakdown (clearance d d2Equation (3) shall be used for interpolation for a certain thickness d (see also Figure 3): mmkV667,125,0+=dE (3) NOTE In this context, the electric field is considered to be approximately uniform if the deviatio

26、ns are less than 20 % from the average value of the field strength. 19 EN 60664-4:2006 0,01 0,1 1 10 d/mm0,1 1 10 E/kV/mm IEC 1347/05 Key E field strength Figure 3 Permissible field strength for dimensioning of solid insulation according to Equation (3) The use of the field strength for dimensioning

27、 of solid insulation requires an approximately uniform field distribution with no voids or air gaps in between. If the field strength cannot be calculated (because the field is not uniform) or if the peak value is higher than given from Equation (3) or Figure 3 respectively or if the presence of voi

28、ds or air gaps cannot be excluded or for higher frequencies than 10 MHz, a withstand test or a PD-test with high-frequency voltage is required. The first applies to short time stresses the second applies to long time stresses according to 3.3.3.2.2 of Part 1. 7 High-frequency testing 7.1 Basic requi

29、rements The following tests are conducted at the frequency of the applied voltage: verification of the short-time dielectric strength for clearances and for solid insulation through use of a high-frequency a.c. voltage test; verification that no partial discharges occur under steady-state conditions

30、 of high-frequency voltage application. EN 60664-4:2006 20 Due to the large capacitive load at high-frequency, high-frequency testing is primarily applicable to components and subassemblies. If an additional high-voltage test on complete equipment is required, this test can be performed according to

31、 4.1.2 of Part 1 with power-frequency voltage. 7.2 Test voltage source Test voltage sources are given in Clause D.1. 7.3 Conditioning If not otherwise specified by technical committees, the test shall be performed with a new test specimen. Conditioning of the specimen by temperature and humidity tre

32、atment is intended to represent the most severe normal service conditions, expose possible weaknesses that are not present in the new condition. The conditioning methods described in 4.1.2.1 of Part 1 also apply for high-frequency testing. 7.4 High-frequency breakdown test This test is similar to th

33、e high-voltage test at power-frequency (see 4.1.2.3 of Part 1). 7.4.1 Test method High-frequency withstand capability is influenced by equipment temperature and environmental conditions. Therefore the test shall be performed under the most severe conditions that can be encountered in service, includ

34、ing the temperature rise caused by normal operation of the equipment. The test duration is 1 min. 7.4.2 Test result No breakdown shall occur during the test duration. After the test, no visible damage (burning, melting etc.) shall occur. 7.5 High-frequency partial discharge test 7.5.1 General consid

35、erations The general methods for partial discharge testing are described in IEC 60270. For PD-testing of low-voltage equipment 4.1.2.4 of Part 1 and Annex C of Part 1 are applicable, but for a test with high-frequency voltage changes are required in the test equipment and methods that are specified

36、in this standard. In order to minimize the risk of test sample degradation, a PD-testing should be performed with precise procedures and measurements and with test voltages in the range of the PD-inception voltage. For the failure criterion, low PD-levels have to be specified, normally below 10 pC.

37、As the specified PD-extinction voltage can be determined with limited accuracy and is influenced by additional parameters such as temperature and humidity which are not usually 21 EN 60664-4:2006 taken into account during testing, the PD-extinction voltage must include a safety factor of F1= 1,2 tim

38、es the highest periodic peak voltages (see 4.1.2.4 of Part 1). For reinforced insulation a more stringent risk assessment is necessary and an additional safety factor of F3= 1,25 is required for the PD-extinction voltage (see 4.1.2.4 of Part 1). The PD-test is primarily a component test, but testing

39、 of equipment is also possible. In that case localizing the PD-source can be difficult and the measured PD-magnitude will be a function of position within the apparatus. During type testing, the PD-test will verify the proper design of the insulation system, the appropriate selection of the insulati

40、on materials, and proper manufacturing processes. Such tests are also very useful during equipment design. By performing sampling and routine testing, the entire manufacturing process can be verified, which is of fundamental importance for quality insurance. Due to the high-frequency test voltage, c

41、areful screening of the test system by conductive enclosures is required to avoid interfering with other electronics in the vicinity. Such screening measures are generally sufficient to meet the required interference level during PD-measurements. 7.5.2 Test method Due to the high risk of deteriorati

42、on of the test specimen at high-frequency voltage, the rate of voltage rise should be as high as possible without causing overshoot of the test voltage. In general, the noise level during high-frequency partial discharge testing will be significantly higher than during power frequency testing. 7.5.3

43、 Test equipment The measurement of partial discharges at high-frequency voltage is more difficult because the test voltage and the partial discharge signal can have overlapping frequency spectra which require appropriate methods of separation (filtering). As the frequency of the test voltage can var

44、y over a wide range, tuned notch filters will be necessary. The centre frequency of these filters shall be tuned to the frequency of the test voltage. It is much more difficult to separate the signal of non-sinusoidal test voltage sources from the PD-signal; therefore such tests are not recommended

45、within the scope of this standard. For measuring the PD-intensity, a digital storage oscilloscope is used in combination with a band-stop filter in order to suppress the high-frequency test voltage. Examples of partial discharge test circuits with high-frequency voltage are shown in Clause D.2. The

46、partial discharge detection is performed by digital integration with a digital storage oscilloscope of high sampling rate. 7.5.4 Test circuit The PD-measurement is performed through detection of the PD-current. For this purpose, a measuring impedance Rmis connected in series with the test specimen.

47、The voltage drop across this impedance is applied across a band-stop filter to one channel of a digital storage oscilloscope with high bandwidth (at least 100 MHz) so that together with the test circuit consisting of lumped elements, a total bandwidth of 60 MHz can be obtained. The band-stop filter

48、removes the voltage drop caused by the capacitive current feeding the test specimen. By this technique a PD-sensitivity of 5 pC can be obtained. EN 60664-4:2006 22 The high-frequency test voltage is measured with a high-frequency voltmeter and the waveshape is monitored on the second channel of the

49、digital storage oscilloscope. For further details of the test circuit see D.2.2. 7.5.5 Required bandwidth of the test circuit In the following evaluation, the test circuit has a 1st order low-pass transfer characteristic (PT1-characteristic) resulting in a lower cut-off frequency of zero and an upper cut-off frequency (3 dB) fcthat is equal to the bandwidth. Considerations with respect to the effect of possible resonance points or the lower cut-off frequency