www bzfxw com BRITISH STANDARD BS EN 61000 2 9 1996 IEC 1000 2 9 1996 Electromagnetic compatibility (EMC) — Part 2 Environment — Section 9 Description of HEMP environment — Radiated disturbance — Basi[.]
BRITISH STANDARD Electromagnetic compatibility (EMC) — Part 2: Environment — Section 9: Description of HEMP environment — Radiated disturbance — Basic EMC publication The European Standard EN 61000-2-9:1996 has the status of a British Standard ICS 29.020 BS EN 61000-2-9:1996 IEC 1000-2-9: 1996 BS EN 61000-2-9:1996 Committees responsible for this British Standard The preparation of this British Standard was entrusted to Technical Committee GEL/210, Electromagnetic compatibility, upon which the following bodies were represented: Association of Consulting Scientists Association of Control Manufacturers (TACMA (BEAMA Ltd.)) Association of Manufacturers of Domestic Electrical Appliances Association of Manufacturers of Power Generating Systems BEAMA Ltd BEAMA Metering Association (BMA) British Industrial Truck Association British Lighting Association for the Preparation of Standards (BRITLAPS) British Telecommunications plc Building Automation and Mains Signalling Association (BAMSA) (BEAMA Ltd.) Department of Trade and Industry (Standards Policy Unit) Department of Health Electrical Installation Equipment Manufacturers’ Association (BEAMA Ltd.) Electricity Association ERA Technology Ltd Federation of the Electronics Industry GAMBICA (BEAMA Ltd.) Health and Safety Executive Induction and Dielectric Heating Manufacturers’ Association Institution of Electrical Engineers International Association of Broadcasting Manufacturers Lighting Industry Federation Ltd Ministry of Defence Motor Industry Research Association National Air Traffic Services National Physical Laboratory Power Supply Manufacturers’ Association (PSMA (BEAMA Ltd.)) Professional Lighting and Sound Association Radiocommunications Agency Rotating Electrical Machines Association (BEAMA Ltd.) Society of British Gas Industries Society of Motor Manufacturers and Traders Limited Transmission and Distribution Association (BEAMA Limited) Co-opted members 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 December 1996 © BSI 10-1998 Amendments issued since publication Amd No Date Comments The following BSI references relate to the work on this standard: Committee reference GEL/210 Draft for comment 92/34647 DC ISBN 580 26354 标准分享网 www.bzfxw.com 免费下载 BS EN 61000-2-9:1996 Contents Committees responsible National foreword Foreword Text of EN 61000-2-9 List of references Page Inside front cover ii Inside back cover ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ © BSI 10-1998 i BS EN 61000-2-9:1996 National foreword This British Standard has been prepared by Technical Committee GEL/210 and is the English language version of EN 61000-2-9:1996 Electromagnetic compatibility (EMC) Part 2: Environment Section 9: Description of HEMP environment — Radiated disturbance — Basic EMC publication, published by the European Committee for Electrotechnical Standardization (CENELEC) It is identical with IEC 1000-2-9:1996, published by the International Electrotechnical Commission (IEC) IEC 1000 has been designated a Basic EMC publication for use in the preparation of dedicated product, product family and generic EMC standards IEC 1000 will be published in separate Parts in accordance with the following structure — Part 1: General; — Part 2: Environment; — Part 3: Limits; — Part 4: Testing and measurement techniques; — Part 5: Installation and mitigation guidelines; — Part 6: Generic standards; — Part 9: Miscellaneous Cross-reference Publication referred to Corresponding British Standard IEC 50 (161):1990 BS 4727 Glossary of electrotechnical, power, telecommunication, electronics, lighting and colour terms Part Terms common to power, telecommunications and electronics Group 09:1991 Electromagnetic compatibility ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ 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 document comprises a front cover, an inside front cover, pages i and ii, the EN title page, pages to 22, an inside back cover 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 cover © BSI 10-1998 ii 标准分享网 www.bzfxw.com 免费下载 EUROPEAN STANDARD EN 61000-2-9 NORME EUROPÉENNE May 1996 EUROPÄISCHE NORM ICS 33.100 Descriptors: Environments, pulses, electromagnetism, explosions, nuclear reactions, nuclear energy, electromagnetic compatibility, electromagnetic waves, wave forms, description English version Electromagnetic compatibilty (EMC) Part 2: Environment Section 9: Description of HEMP environment — Radiated disturbance Basic EMC publication (IEC 1000-2-9:1996) Compatibilité électromagnétique (CEM) Partie 2: Environnement Section 9: Description de l’environnement IEMN-HA Perturbations rayonnées Publication fondamentale en CEM (CEI 1000-2-9:1996) Elektromagnetische Verträglichkeit (EMV) Teil 2: Umgebungsbedingungen Hauptabschnitt 9: Beschreibung der HEMP-Umgebung-Stöhrstrahlung EMV-Grundnorm (IEC 1000-2-9:1996) ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ This European Standard was approved by CENELEC on 1996-03-05 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 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 other 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, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Central Secretariat: rue de Stassart 35, B-1050 Brussels © 1996 Copyright reserved to CENELEC members Ref No EN 61000-2-9:1996 E EN 61000-2-9:1996 Foreword Page The text of document 77C/27/FDIS, future edition of IEC 1000-2-9, prepared by SC 77C, Immunity to high altitude nuclear electromagnetic pulse (HEMP), of IEC TC 77, Electromagnetic compatibility, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as EN 61000-2-9 on 1996-03-05 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) 1996-12-01 – latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 1996-12-01 Annexes designated “normative” are part of the body of the standard In this standard, annex ZA is normative Annex ZA has been added by CENELEC Contents Figure — Geometry for the definition of the plane wave Figure — Geomagnetic dip angle Figure — Schematic representation of the early-time HEMP from a high-altitude burst Figure — HEMP tangent radius as a function of height of burst (HOB) Figure — Typical variations in peak electric fields on the earth’s surface for burst altitudes between 100 km and 500 km and for ground zero between 30º and 60º northern latitude The data are applicable for yields of a few hundred kilotons or more Figure — Different waveforms for three typical cases indicated in Figure (points A, B, C) and the composite curve fit Figure — HEMP early-time behaviour (electric field component) Figure — Standard late-time HEMP waveform Figure 10 — Complete standard HEMP time waveform Figure 11 — Amplitude spectrum of each HEMP component Figure 12 — Fraction of energy fluence from f = 103 Hz to f1 Figure 13 — Representation of incident, reflected and refracted waves Figure 14 — Calculated total horizontal electric field as a sum of the incident plus reflected fields for a HEMP (early-time part only) Figure 15 — Calculated total horizontal electric field as a sum of the incident plus reflected fields for a HEMP (early-time part only) for different angles of elevation Figure 16 — Calculated transmitted horizontal electric fields for a HEMP (early-time only) ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Foreword Scope and object Normative reference General Definitions Description of HEMP environment, radiated parameters 5.1 High-altitude bursts 5.2 Spatial extent of HEMP on the earth’s surface 5.3 HEMP time dependence 5.4 Magnetic field component 5.5 HEMP amplitude and energy fluence spectrum 5.6 Weighting of the early, intermediate and late-time HEMP 5.7 Reflection and transmission Annex ZA (normative) Normative references to international publications with their corresponding European publications Figure — Geometry for the definition of polarization and of the angles of elevation ψ and azimuth φ Page 3 6 7 15 5 10 12 14 14 16 16 18 19 20 21 15 17 17 22 © BSI 10-1998 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 Scope and object General This section of IEC 1000-2 defines the high-altitude electromagnetic pulse (HEMP) environment that is one of the consequences of a high-altitude nuclear explosion Those dealing with this subject consider two cases: — high-altitude nuclear explosions; — low-altitude nuclear explosions For civil systems, the most important case is the high-altitude nuclear explosion In this case, the other effects of the nuclear explosion: blast, ground shock, thermal and nuclear ionizing radiation are not present at the ground level However the electromagnetic pulse associated with the explosion may cause disruption of, and damage to, communication, electronic and electric power systems thereby upsetting the stability of modern society The object of this standard is to establish a common reference for the HEMP environment in order to select realistic stresses to apply to victim equipment for evaluating their performance A high-altitude (above 30 km) nuclear burst produces three types of electromagnetic pulses which are observed on the earth’s surface: – – – early-time HEMP intermediate-time HEMP late-time HEMP (fast); (medium); (slow): Historically, most interest has been focused on the early-time HEMP which was previously referred to as simply “HEMP” Here we will use the term high-altitude “EMP” or “HEMP” to include all three types The term NEMP1) covers many categories of nuclear EMP’s including those produced by surface bursts (SREMP)2) or created on space systems (SGEMP)3) Because the HEMP is produced by a high-altitude detonation, we not observe other nuclear weapon environments such as gamma rays, heat and shock waves at the earth’s surface HEMP was reported from high-altitude U.S nuclear tests in the South Pacific during the early 1960’s, producing effects on electronic equipment far from the burst location ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Normative reference The following normative document contains provisions which, through reference in this text, constitute provisions of this section of IEC 1000-2 At the time of publication, the edition indicated was valid All normative documents are subject to revision, and parties to agreements based on this section of IEC 1000-2 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below Members of IEC and ISO maintain registers of currently valid International Standards IEC 50(161):1990, International Electrotechnical Vocabulary — Chapter 161: Electromagnetic compatibility 1) NEMP: Nuclear ElectroMagnetic Pulse 2) SREMP: Source Region EMP 3) SGEMP: System Generated EMP © BSI 10-1998 EN 61000-2-9:1996 Definitions ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Figure — Geometry for the definition of polarization and of the angles of elevation ψ and azimuth φ 4.1 angle of elevation in the vertical plane Ψ angle ψ measured in the vertical plane between a flat horizontal surface such as the ground and the propagation vector (see Figure 1) 4.2 azimuth angle, φ angle between the projection of the propagation vector on the ground plane and the principal axis of the victim object (z axis for the transmission line of Figure 1) 4.3 composite waveform waveform which maximizes the important features of a group of waveforms 4.4 coupling interaction of the HEMP field with a system to produce currents and voltages on system surfaces and cables Voltages result from the induced charges and are only defined at low frequencies with wavelengths larger than the surface or gap dimensions 4.5 direction of propagation of the electromagnetic wave direction of the propagation vector k , perpendicular to the plane containing the vectors of the electric and the magnetic fields (see Figure 2) 4.6 E1, E2, E3 terminology for the early, intermediate and late-time HEMP electric fields 4.7 EMP any electromagnetic pulse, general description 4.8 energy fluence integral of the Poynting vector over time; presented in units of J/m2 4.9 geomagnetic dip angle, θdip dip angle of the geomagnetic flux density vector B e, measured from the local horizontal in the magnetic north-south plane θdip = 90º at the magnetic north pole, – 90º at the magnetic south pole © BSI 10-1998 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 Figure — Geometry for the definition of the plane wave ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Figure — Geomagnetic dip angle 4.10 ground zero 4.13 HOB point on the earth’s surface directly below the burst; sometimes called surface zero height of burst 4.11 HEMP high-altitude nuclear EMP 4.12 high-altitude (nuclear explosion) height of burst above 30 km altitude © BSI 10-1998 4.14 horizontal polarization an electromagnetic wave is horizontally polarized if the magnetic field vector is in the incidence plane and the electric field vector is perpendicular to the incidence plane and thus parallel to the ground plane (Figure 1) (This type of polarization is also called perpendicular or transverse electric (TE).) EN 61000-2-9:1996 4.15 incidence plane Description of HEMP environment, radiated parameters plane formed by the propagation vector and the normal to the ground plane 5.1 High-altitude bursts 4.16 low-altitude (nuclear explosion) height of burst below km altitude 4.17 NEMP nuclear EMP; all types of EMP produced by a nuclear explosion 4.18 polarization orientation of the electric field vector 4.19 prompt radiation nuclear energy which leaves an explosion within µs 4.20 SREMP source region EMP; the NEMP produced in any region where prompt radiation is also present producing currents (sources) in the air 4.21 tangent point When a nuclear weapon detonates at high altitudes, the prompt radiation (x-rays, gamma rays and neutrons) deposit their energy in the dense air below the burst In this deposition (source) region, the gamma rays of the nuclear explosion produce Compton electrons by interactions with the molecules of the air These electrons are deflected in a coherent manner by the earth’s magnetic field These transverse electron currents produce transverse electric fields which propagate down to the earth’s surface This mechanism describes the generation of the early-time HEMP (Figure 4) which is characterized by a large peak electric field (tens of kilovolts per meter), a fast rise time (nanoseconds), a short pulse duration (up to about 100 ns) and a wave impedance of 377 Ω The early-time HEMP exposes the earth’s surface within line-of-sight of the burst and is polarized transverse to the direction of propagation and to the local geomagnetic field within the deposition region In the northern and southern latitudes (i.e far from the equator) this means that the electric field is predominantly oriented horizontally (horizontal polarization) Immediately following the initial fast HEMP transient, scattered gamma rays and inelastic gammas from weapon neutrons create additional ionization resulting in the second part (intermediate time) of the HEMP signal This second signal is on the order of 10 V/m to 100 V/m and can occur in a time interval from 100 ns to tens of milliseconds The last type of HEMP, late-time HEMP, also designated magnetohydrodynamic EMP (MHD-EMP) is generated from the same nuclear burst Late-time HEMP is characterized by a low amplitude electric field (tens of millivolts per meter), a slow rise time (seconds), and a long pulse duration (hundreds of seconds) These fields will cause similar induction currents in power lines and telephone networks as those associated with magnetic storms often observed in Canada and the Nordic countries Late-time HEMP can interact with transmission and distribution lines to induce currents that result in harmonics and phase imbalances which can potentially damage major power system components (such as transformers) ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ any point on the earth’s surface where a line drawn from the burst is tangent to the earth 4.22 tangent radius distance measured along the earth’s surface between ground zero and any tangent point 4.23 vertical polarization an electromagnetic wave is vertically polarized if the electric field vector is in the incidence plane and the magnetic field vector is perpendicular to the incidence plane and thus parallel to the ground plane (Figure 1) (This type of polarization is also called parallel or transverse magnetic (TM).) © BSI 10-1998 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 Figure — Different waveforms for three typical cases indicated in Figure (points A, B, C) and the composite curve fit ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ For these cases, the electric field early-time behaviour in free space of this wave is given by: (1) It should be emphasized that the early-time HEMP is an incident field, and reflections from the ground shall be treated separately (see 5.7) The incident electric field is polarized perpendicular to the direction of propagation and the earth’s magnetic field Because of this relationship, the local vertical component of the incident early-time HEMP electric field is maximum to the magnetic east and west of the burst at the Earth’s tangent point Toward the magnetic north and south, the local vertical electric field component is zero Since it is not known where the burst will be located relative to a given observer, the vertical and horizontal electric field component fractions can be defined as: where E1 is given in volts per meter; t is in seconds (2) A plot of equation (1) is given in Figures 8a and 8b Figure 8a shows the pulse rise characteristics The pulse decay behaviour is given in Figure 8b Because this waveform attempts to bound features of any early-time HEMP waveform, it is considered a standard waveform The pulse has a peak amplitude of 50 kV/m, a 10 % to 90 % rise time of 2,6 ns – 0,1 ns = 2,5 ns, a time to peak of 4,8 ns, and a pulse width at half maximum of 23 ns The energy fluence of the early-time waveform is 0,114 J/m2 Figure 8c provides information to establish θdip © BSI 10-1998 10 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ © BSI 10-1998 11 EN 61000-2-9:1996 ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Figure — HEMP early-time behaviour (electric field component) © BSI 10-1998 12 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 where 5.3.2 Intermediate-time HEMP waveform The intermediate-time HEMP is characterized by an amplitude of 10 V/m to 100 V/m for times between approximately 0,1 µs and 0,01 s The field has similarity to the early-time HEMP in terms of being defined as an incident radiation field with the same polarization as the early-time HEMP After earth reflection, the electric field will be oriented mainly vertically with a small horizontal component The electric field intermediate-time behaviour in free space of this wave is given by: (5) (3) and (6) where ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ E2 is given in volts per meter; t is in seconds A plot of this waveform is shown in Figure 10 This waveform has a peak amplitude of 100 V/m and a pulse width at half maximum of 693 µs The energy fluence of the wave is 0,0133 J/m2 5.3.3 Late-time HEMP waveform The late-time portion of the HEMP waveform is produced by the magnetohydrodynamic (MHD) effect and produces electric fields in the earth of tens of millivolts per meter for times between s and 1000 s The induced electric field is oriented horizontally The electric field late-time waveform in the earth for a deep ground conductivity (to a depth of 100 km) of sg = 10–4 S/m is given by: (4) © BSI 10-1998 The field is defined in volts per meter and the times (t and t) are in seconds A plot of this waveform is shown in Figure where sg is the ground conductivity For other ground conductivities, E3 ~ sg–1/2 The resultant waveform has a peak electric field of 38 mV/m, a rise time of approx 0,9 s, a positive pulse width of 20 s and a negative pulse width of 130 s 5.3.4 The complete standard HEMP electric field time waveform Figure 10 shows the time behaviour of all three contributions to the HEMP It is emphasized that E1(t) and E2(t) are incident waves with identical polarization while E3(t) is an induced electric field in the earth with horizontal orientation 13 EN 61000-2-9:1996 ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Figure — Standard late-time HEMP waveform Figure 10 — Complete standard HEMP time waveform © BSI 10-1998 14 标准分享网 www.bzfxw.com 免费下载 EN 61000-2-9:1996 5.4 Magnetic field component For frequencies f above 1,6 kHz and for a distance from source to object of at least 30 km (height of source region, see Figure 4), the following well-known far-field criterion is fulfilled: For the general analytic time waveform used in equations (1), (3), (5), and (6), the Fourier transform is analytic and is given by: (10) (7) where where λ is the wavelength; c denotes the velocity of light In this case, the criterion is satisfied for times less than 100 µs Therefore the waveforms shown in Figure 10 can be converted to magnetic fields by dividing the electric fields by Z0 = 120 π Ω for times less than 100 µs This means that equation (1) can be used to calculate the peak incident magnetic field: m may be 1, 2, i or j; w is a phase shift (w = for E1 and E2, w = 2πf for Ei and Ej) Figure 11 shows the amplitude density spectrum of the high-altitude EMP electric field Each of the components is shown separately The power spectrum S(f) describes the energy density as a function of frequency (i.e., for the far field criterion of f > 103 Hz): (11) (8) where where Zo = 120 π Ω ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ E01 is given in volts/meter; Z0 is given in ohms; The energy fluence of the early-time E1 waveform can be found by integrating equation (11) in the frequency domain giving: H01 is given in amperes/meter 5.5 HEMP amplitude and energy fluence spectrum (12) Many of the significant HEMP energy collectors are particularly frequency selective It is thus important to find the HEMP energy distribution in the frequency domain The Fourier transform of the generalized HEMP electric-field time waveform is used to find the relative contribution of the constituent frequencies: Figure 12 shows the cumulative amount of energy fluence of the early-time HEMP as a function of frequency (9) © BSI 10-1998 15 EN 61000-2-9:1996 Figure 11 — Amplitude spectrum of each HEMP component ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Figure 12 — Fraction of energy fluence from f = 103 Hz to f1 © BSI 10-1998 16 标准分享网 www.bzfxw.com 免费下载