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GB/T 18039.10-2018: PDF in English (GBT 18039.10-2018) GB/T 18039.10-2018
Electromagnetic compatibility(EMC)--Environment--Description of HEMP environment--Radiated disturbance
ICS 33.100
L06
National Standards of People's Republic of China
Electromagnetic compatibility environment
HEMP environment describes radiated disturbance
[IEC 61000-2-9.1996, Electromagneticcompatibility (EMC)-
Part 2.Environment-Section9. DescriptionofHEMPenvironment-
Radiateddisturbance, IDT]
Published on.2018-05-14
2018-12-01 implementation
State market supervision and administration
China National Standardization Administration issued
Content
Foreword III
1 range 1
2 Normative references 1
3 Overview 1
4 Terms and Definitions 1
5 Description of high-altitude electromagnetic pulse environment, radiation parameter 4
5.1 High-altitude nuclear explosion 4
5.2 HEMP on the ground scope 5
5.3 HEMP Time Domain Waveform 6
5.4 Magnetic field component 11
5.5 HEMP amplitude spectrum and energy fluence spectrum 11
5.6 Impact weights of early, intermediate and late HEMPs 13
5.7 Reflection and Transmission 13
Foreword
The Electromagnetic Compatibility Environment is divided into the following sections.
---GB /Z 18039.1-2000 Classification of electromagnetic environment in electromagnetic compatibility environment;
---GB /Z 18039.2-2000 Electromagnetic compatibility environment industrial equipment power supply low frequency conducted disturbance emission level assessment;
---GB/T 18039.3-2017 Electromagnetic compatibility environment common low-voltage power supply system low-frequency conduction disturbance and signal transmission
Capacity level
---GB/T 18039.4-2017 Compatibility level of low frequency conducted disturbance in electromagnetic compatibility environment factory;
---GB /Z 18039.5-2003 Electromagnetic compatibility environment public power supply system low frequency conduction disturbance and electromagnetic transmission of signal transmission
surroundings;
---GB /Z 18039.6-2005 Electromagnetic compatibility environment Low frequency magnetic field in various environments;
---GB /Z 18039.7-2011 Electromagnetic compatibility environment, voltage sag, short-term interruption and its measurement system
Counting results
---GB/T 18039.8-2012 Electromagnetic compatibility environment High altitude nuclear electromagnetic pulse (HEMP) environment describes conducted disturbance;
---GB/T 18039.9-2013 Electromagnetic compatibility environment common medium voltage power supply system low frequency conduction disturbance and signal transmission
Capacity level
This part is the 10th part of GB/T 18039.
This part is drafted in accordance with the rules given in GB/T 1.1-2009.
This section uses the translation method equivalent to IEC 61000-2-9.1996 Electromagnetic Compatibility (EMC) Part 2. Environment Section 9.
The HEMP environment describes radiated disturbances.
This section has made the following editorial changes.
--- In line with the existing standard series, change the name of this part to "Electromagnetic compatibility environment HEMP environment describes radiated disturbance".
--- According to the original meaning, move the formula in the upper left corner of the original picture 5 to the footnote of Figure 5.
--- According to Chinese writing habits, the explanatory text of the original texts 14a), 14b) is placed before the figure in Figure 14.
--- According to the Chinese writing habits, the explanatory text of the original text 15 is placed before the figure in Fig. 15.
--- According to Chinese writing habits, the explanatory text of the original texts 16a), 16b) is placed before the figure in Figure 16.
This part is proposed and managed by the National Electromagnetic Compatibility Standardization Technical Committee (SAC/TC246).
This section was drafted by. Tsinghua University.
The main drafters of this section. Meng Cui, Li Xin, Tan Zhaojie, Fan Yafang.
Electromagnetic compatibility environment
HEMP environment describes radiated disturbance
1 Scope
This part of the Electromagnetic Compatibility Environment defines a high altitude electromagnetic pulse (HEMP) environment, one of the effects of high altitude nuclear explosions.
There are two situations to consider when studying this topic.
---High altitude nuclear explosion;
--- Low-altitude nuclear explosion.
For civilian systems, the most serious situation is a high-altitude nuclear explosion. In this case, other effects of nuclear explosions, such as explosions,
Ground impact, heat radiation and ionizing radiation will not affect the ground. However, electromagnetic pulses generated by nuclear explosions may cause communication systems.
Damage and destruction of the system, electronics and power systems, which in turn affects the stability of modern society.
The purpose of this section is to establish a general reference for the HEMP environment, to select the actual environmental parameters for sensitive devices, and to evaluate their sensitivity.
Sensitivity.
2 Normative references
The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article.
Pieces. For undated references, the latest edition (including all amendments) applies to this document.
GB/T 4365-2003 Electrotechnical terminology electromagnetic compatibility [idtIEC 60050 (161)..1990]
3 Overview
High-altitude (above 30km) nuclear explosions produce three types of electromagnetic pulses that can be observed on the Earth's surface.
--- Early high altitude electromagnetic pulse (fast);
--- Medium-term high altitude electromagnetic pulse (medium);
--- Late high altitude electromagnetic pulse (slow).
Historically, most of the attention has been focused on early high-altitude electromagnetic pulses, which once briefly recognized high-altitude electromagnetic pulses.
It means the early high-altitude electromagnetic pulse. And here, the term "high altitude EMP" or "HEMP" we use will include all three types of electricity.
Magnetic pulse. The term nuclear electromagnetic pulse (NEMP1) covers many categories, including nuclear electromagnetic pulses in the source region generated by ground nuclear explosions.
(SREMP2)) and system electromagnetic pulse (SGEMP3) excited in the space system.
Since high-altitude electromagnetic pulses (HEMP) are generated by high-altitude nuclear explosions, there will be no other nuclear weapons effects on the ground, such as gamma rays, heat.
Radiation, shock waves, etc. In the early 1960s, the United States conducted high-altitude nuclear explosion tests in the South Pacific, resulting in electronic settings far from the explosion point.
For the first time in the report of the huge effect, the term high-altitude electromagnetic pulse (HEMP) appeared.
1) NEMP. Nuclear electromagnetic pulse.
2) SREMP. Nuclear electromagnetic pulse in the source area.
3) SGEMP. System electromagnetic pulse.
4 Terms and definitions
The following terms and definitions as defined in GB/T 4365-2003 apply to this document.
4.1
Vertical plane elevation angleangleoflevationintheverticalplane
In the vertical plane of the horizontal plane, the angle between the direction of propagation and the horizontal plane (ground plane) (see Figure 1).
Figure 1 Definition of polarization, elevation angle Ψ and azimuth Φ
4.2
Azimuth azimuthangle
The projection of the propagation direction on the ground plane is at an angle to the principal axis of the target (the Z axis for the transmission line in Figure 1).
4.3
Composite waveform compositewaveform
A waveform that maximizes the most important features of a set of waveforms.
4.4
Coupling coupling
High-altitude electromagnetic pulses interact with the system to generate current and voltage across the system surface and cables. The voltage is generated by the induced charge, only
Meaning low frequency and wavelength is greater than surface or gap size.
4.5
Direction of electromagnetic wave propagation directionofpropagationoftheelectromagneticwave
Propagation vector k
The direction of → is perpendicular to the plane of the electric and magnetic field vectors (see Figure 2).
Figure 2 Geometric definition of plane waves
4.6
E1, E2, E3
Refers to the electric fields of the early, middle and late high altitude electromagnetic pulses, respectively.
4.7
Electromagnetic pulse electromagneticpulse; EMP
Any electromagnetic pulse, collectively.
4.8
Energy flow
The time integral of the Poynting vector, in J/m2.
4.9
Geomagnetic dip geomagneticdipangle
Θdip
The inclination of the earth's magnetic flux flux density vector B→e, that is, the angle between the north-south plane and the horizontal plane where the magnetic field is located at the point, in the north magnetic field
Θdip=90°, in the south of the earth's magnetic field is θdip=-90° (see Figure 3).
Figure 3 Earth magnetic field dip
4.10
Ground floor projection point groundzero
A point at which a heart bursts vertically onto the surface of the earth, sometimes referred to as a surface zero.
4.11
HEMP high-altitudenuclearEMP
High altitude electromagnetic pulse.
4.12
High altitude (nuclear explosion) high-altitude(nuclearexplosion)
Explosion with a height of more than 30km.
4.13
Core height burstofburst; HOB
The height of the heart.
4.14
Horizontal polarization horizontalpolarization
If an electromagnetic wave has a magnetic field vector at the incident surface and the electric field vector is perpendicular to the incident surface and parallel to the ground plane, it is called the horizontal pole.
(Figure 1). This polarization field is also known as the transverse electric field (TE).
4.15
Incident plane incubationplane
A plane formed by the propagation vector and the normal to the ground plane.
4.16
Low-altitude (nuclearexplosion)
A nuclear explosion with a height of less than 1km.
4.17
Nuclear electromagnetic pulse nuclearEMP; NEMP
A general term for all types of electromagnetic pulses generated by nuclear explosions.
4.18
Polarization polarization
Electric field vector direction.
4.19
Instant radiation
Nuclear energy radiated within 1 μs after the explosion.
4.20
Source area electromagnetic pulse sourceregionEMP; SREMP
A nuclear electromagnetic pulse generated by a transient radiation that excites a current (source) in the air.
4.21
Cut point tangentpoint
A little on the surface of the earth, from the heart to the surface of the earth, a tangent to the intersection of the tangent and the earth.
4.22
Tangential radius
The length of the point along the surface of the earth projected from the ground floor to any point.
4.23
Vertical polarization verticalpolarization
If an electromagnetic wave has an electric field vector at the incident surface and the magnetic field vector is perpendicular to the incident surface and parallel to the ground plane, it is called a vertical pole.
(Figure 1). This polarization field is also known as the transverse magnetic field (TM).
5 Description of high-altitude electromagnetic pulse environment, radiation parameters
5.1 High-altitude nuclear explosion
When a nuclear weapon explodes at high altitude, most of the instantaneous radiation (such as X-rays, gamma rays, and neutrons) generated by the explosion is below the heart.
High density atmospheric deposition. In the deposition zone (also known as the source zone), gamma rays react with air molecules to produce Compton electrons.
These moving electrons deflect under the action of the Earth's magnetic field, producing a lateral current that produces a transverse electric field and propagates to the Earth.
surface. The above mechanism describes the production process of early HEMP, as shown in Figure 4. The description parameters of the early HEMP are as follows. peak field strength
Large (tens of kilovolts per meter), fast rising front (several nanoseconds), short duration (up to 100ns), and wave impedance of 377Ω. Early HEMP spoke
The range of the shot is the surface of the earth within the range of the blasting field. The direction of polarization of the electric field and its direction of propagation and the direction of the local geomagnetic field in the sedimentary zone
straight. In the northern and southern hemispheres far enough away from the equator, the polarization direction of the early HEMP electric field is almost horizontal.
Immediately following the early fast HEMP transient pulse, additional ionization occurs from the scattered gamma rays and hard gamma rays generated by the explosive radiation neutrons.
The second part (interim) HEMP signal is generated. The amplitude of this part of the signal is in the range of 10V/m to 100V/m and the duration is 100ns.
To tens of milliseconds.
The last part of the HEMP signal, the late HEMP, is also known as the magnetohydrodynamic electromagnetic pulse (MHD-EMP). Late
The HEMP electric field has a small amplitude (tens of V/m), a rising front (several seconds), and a long duration (several hundred seconds). It will be in the power line network and communication network
Current is induced on the network, and its effects are closely related to solar magnetic storms in power lines and communication networks in countries such as Canada and Northern Europe.
The effect on the above is similar. Late HEMP interacts with the communication network and the grid to generate induced currents that will cause harmonic and phase imbalances.
This can cause damage to major power system components such as transformers.
Figure 4 High-altitude nuclear explosion produces early HEMP diagram
5.2 HEMP on the ground
At high altitude nuclear explosions, the extent of HEMP's action on the ground depends on the explosion height and explosive equivalent. At different locations within the scope of action
Observed electric field signals vary widely (such as peak, rise time, duration, or polarization), for example, high altitude nucleus in the northern hemisphere
Explosion, the maximum peak electric field (denoted as Emax) appears on the south side of the ground-breaking ground projection point, up to 50kV/m (this value depends on the explosion height and explosion
Fried equivalent). Figure 5 depicts the relationship between the tangential radius of the early HEMP's range of action on the Earth's surface and the height of the explosion (HOB). For example, high
At 50km, the early HEMP has a radius of action of 800km on the ground; when the explosion is 500km, the radius of action is 2500km. Figure 6 shows
For different explosion heights, the early HEMP changes in peak field strength over the ground.
aRT≈110 HOB, HOB≤500km.
Fig. 5 Relationship between tangential radius and explosion height of HEMP on the surface of the Earth
5.3 HEMP Time Domain Waveform
In this article, the time domain waveforms of the electric fields represent the early, intermediate, and late HEMP environments, respectively.
5.3.1 Early HEMP Time Domain Waveforms
The early HEMP time domain waveforms at three different positions A, B, and C in FIG. 6 are as shown in FIG. Due to early HEMP on the ground
The incident waveform at different positions changes greatly, and the position of the explosion point cannot be predicted, so a universal HEMP time domain waveform will be constructed.
It is necessary to preserve the rise time of the electric field waveform at the near projection point and the peak value within the maximum peak range. The envelope of the electric field waveform at all positions,
It is a universal waveform in an extreme case. Fourier transform of the frequency domain of all electric fields in the range of early HEMP action
The envelope constructs a more practical and civilian universal electric field waveform, that is, a pulse waveform with a parameter of 2.5 ns/23 ns.
Fig. 6 The projection point of the explosion ground is within 30°~60° north latitude, and the explosion height is within the range of 100km~500km.
Typical variation of the peak electric field (this data applies to the case where the explosive equivalent is 100,000 tons or more)
Figure 7 Figure 6. Early HEMP electric field waveforms at three typical locations (A, B, C) and the composite waveforms of the three
In summary, the early HEMP electric field waveform in free space is as shown in equation (1).
E1(t)=
0 when t≤0
E01·k1(e-a1t-e-b1t) when t≥0{ (1)
E01=50000V/m
A1=4×107s-1
B1=6×108s-1
K1=1.3
In the formula.
E1--- electric field strength in volts per meter (V/m);
t --- time in seconds (s).
Figure 8a) and Figure 8b) are performed according to equation (1), wherein Figure 8a) shows the rising leading edge characteristic of the pulse; Figure 8b) shows the trailing edge of the pulse.
Sex. Since the waveforms in Figures 8a) and 8b) contain features of any of the early HEMPs, this waveform can be considered a standard waveform. The
The peak value of the pulse waveform is 50kV/m, the rising edge of 10%~90% is 2.5ns, the peak time is 4.8ns, and the full width at half maximum is 23ns. Early
The energy fluence of the HEMP waveform is 0.114 J/m2.
It should be emphasized that the early HEMP is an incident field, and the above discussion does not consider the reflection of the ground.
See 5.7 for the situation. Since the direction of polarization of the incident electric field is perpendicular to the direction of propagation of the electromagnetic wave and the direction of the earth's magnetic field, early HEMP is at the ground.
At the tangent point of the surface action range, the local vertical component of the electric field reaches the maximum on the east and west sides of the geomagnetic field at the explosion point, and is zero on the south and north sides.
Since the location of the explosion point is unknown, the vertical and horizontal components of the electric field can be defined by equation (2).
Fv≤cosθdip
Fh≥sinθdip
F2v f2h=1
Ïï
Ïï
(2)
See Figure 8c) for the value of θdip.
a) 0ns~10ns (pulse rising front)
b) 0ns~50ns (pulse fading characteristics)
Figure 8 Early HEMP case (electric field part)
c) θdip-earth magnetic field dip
Figure 8 (continued)
5.3.2 Mid-term HEMP waveform
The medium-term HEMP amplitude ranges from 10 V/m to 100 V/m and the duration is between 0.1 μs and 0.01 s. And early HEMP
Similarly, the mid-term HEMP can also be defined as the incident field of the same polarization direction. After the reflection of the Earth, the horizontal component of the electric field is small,
This is vertical polarization.
The electric field time domain waveform of the mid-term HEMP in free space is as shown in equation (3).
E2(t)=
0 when t≤0
E02·k2(e-a2t-e-b2t) when t≥0{ (3)
E02=100V/m
A2=1000s-1
B2=6×108s-1
Ki=1
In the formula.
E2--- electric field strength in volts per meter (V/m);
t --- time in seconds (s).
Figure 10 shows the above electric field waveform with a peak value of 100 V/m, a pulse half-width of 693 μs, and a fluence of 0.0133 J/m 2 .
5.3.3 Late HEMP
Late HEMP is produced by magnetohydrodynamic effects, and the electric field generated in the Earth is about tens of millivolts per meter. The duration is
Within 1s to 1000s, horizontally polarized.
Under the surface soil conductivity σg=10-4s/m, about 100km deep from the surface, the late HEMP electric field time domain waveform is as shown in formula (4).
E3(t)=Ei(t)-Ej(t) (4)
among them.
Ei(t)=
0 when τ ≤ 0
E0i·ki(e-aiτ-e-biτ) when τ≥0{ (5)
τ=t-1
E0i=0.04V/m
Ai=0.02s-1
Bi=2s-1
Ki=1.058
Ej(t)=
0 when τ ≤ 0
E0j·kj(e-ajτ-e-bjτ) when τ≥0{ (6)
τ=t-1
E0j=0.01326V/m
Aj=0.015s-1
Bj=0.02s-1
Kj=9.481
The electric field strength is in units of V/m and the time unit is s. The above waveform is shown in Fig. 9, where σg is the earth conductivity. To other earth
Conductivity, E3 ~ σ-1/2g.
Figure 9 Late HEMP standard waveform
In Fig. 9, the peak field strength of the waveform is 38 mV/m, the rise time is about 0.9 s, the positive pulse width is 20 s, and the negative pulse width is 130 s.
5.3.4 Complete standard HEMP electric field time domain waveform
Figure 10 shows the sum of the HEMP electric field waveforms of the above three different periods. It should be emphasized that E1(t) and E2(t) are incident
Waves have the same polarization direction; while E3(t) is the electric field induced inside the Earth, horizontally polarized.
Figure 10 Complete HEMP standard time domain waveform
5.4 Magnetic field component
When the electromagnetic wave frequency f is greater than 1.6 kHz and the source is 30 km (source region height, see Figure 4), the following well-known far-field criteria are established.
[See equation (7)].
R≥
2π=
2πf
(7)
In the formula.
λ---wavelength;
c---speed of light.
For HEMP, the above formula is established within 100 μs after the explosion. Therefore, divide the HEMP electric field waveform before 100μs in Figure 10 by
The magnetic field waveform can be obtained after Z0=120πΩ. Thus, the peak value of the incident magnetic field can be obtained from equation (1). (8).
H01=
E01
Z0 =
120π = 132.6
(8)
In the formula.
E01--- electric field strength in volts per meter (V/m);
Z0 ---impedance in ohms (Ω);
H01---Magnetic field strength in ampere per meter (A/m).
5.5 HEMP amplitude spectrum and energy fluence spectrum
Most typical HEMP energy harvesters are frequency selective. Therefore, it is important to obtain the energy spectrum of HEMP. On the top
After the Fourier transform of the HEMP electric field time domain waveform is obtained, the electric field frequency domain waveform can be obtained as shown in equation (9).
(f)=∫
E(t)·e-i2πftdt (9)
For the time domain waveforms of the general analytical form in equations (1), (3), (5), and (6), the analytical form of the Fourier transform is as follows.
Equation (10).
m(f)=
E0m·km(bm -am)
(j2πf am)(j2πf bm)
·e-jφ (10)
In the formula.
M---1, 2, i or j;
φ---phase offset angle (φ1 for E1 and E2; Ei and Ej, φ=2πf).
Figure 11 shows the amplitude density spectrum of the HEMP electric field. E1, E2, and E3 represent HEMPs for 3 different time periods, respectively.
Figure 11. The amplitude spectrum of the HEMP components
The power spectrum S(f) describes the energy density of each frequency point. For example, when f>103Hz, there are.
S(f)=
2E
(f) 2
Z0
(11)
In the formula.
Z0 = 120 π Ω.
By integrating the equation (11) in the frequency domain, the energy fluence of the early HEMP electric field E1 can be obtained as in equation (12).
WT =∫
S(f)·dfWf=∫
F1
S(f)·df (12)
Figure 12 shows the variation of the early HEMP electric field energy fluence in the frequency domain. As can be seen from the figure. at 105Hz, the energy note
The amount is 2%; and at 98 Hz is about 98%, that is, 96% of the energy is deposited in the frequency range of 105 Hz to 108 Hz. This shows that early
The main energy of HEMP is concentrated in the frequency range of 0.1MHz to 100MHz.
Figure 12 Early HEMP partial energy fluence, from f = 103 Hz to f1
As can be seen from Fig. 11, when f < 104 Hz and f < 1 Hz, respectively, the amplitude spectrum of E2 and E3 is higher than the amplitude spectrum of E1. In addition to this
In addition, the total energy fluence of E2 and E3 is only 0.013 J/m2, while the total energy fluence of E1 is 0.144 J/m2. Mid and late HEMP
The energy fluence is negligible compared to the early ones.
However, it is important to emphasize that the electromagnetic field energy received by the "antenna" and conducted to the "sensitive device" depends not only on the total incident energy.
Note WT. Because the voltage and current induced on the internal electronics of the system are also affected by the coupling mechanism, system topology, and impedance matching.
The voltage and current induced on the electronic equipment in the power grid are also affected by the subsequent current after the dielectric breakdown.
5.6 Impact weights of early, intermediate and late HEMP
Due to the small magnitude of the intermediate and late HEMPs, in the published literature, the mid- and late-stage HEMP effects are often overlooked.
slightly. The medium-term 100V/m and the late 40mV/m are negligible compared to the early HEMP 50000V/m electric field peak.
In some cases, the above inferences are valid, especially when the "sensitive" system (subsystem, device) has a small physical size (ie, coupling)
When the area is small, such as a mobile device such as a vehicle. In this case, only the HEMP of the high frequency part can be coupled. However, from the source (electromagnetic field) to the sensitive
The coupling mechanism of the sensing device is frequency dependent.
According to Fig. 11, when the HEMP spectrum gives the influence weights of the early, middle and late HEMPs, the coupling mechanism needs to be considered. If sensitive
When the system is physically large (such as a power system or a long communication line) or a small device connected to a communication line,
It is necessary to consider the role of the intermediate and late HEMP.
5.7 Reflection and transmission
When the early or mid-term HEMP is incident on the ground, part of the electromagnetic pulse energy passes through the interface between the air and the ground, and the rest will reflect.
As shown in Figure 13.
Figure 13 Description of incident, reflected, and refracted waves
In almost all practical situations, the incident electromagnetic field is altered by the structure near the target system. For example, in power lines and underground communication lines
The field near the cable is affected by the ground, so the field acting on the cable is not the incident field, but the total field.
Taking the underground communication cable as an example, the total field is a part of the incident field, that is, the incident field enters the ground after being reflected at the air-ground interface, and then
The part after being absorbed by the soil. For a receiver on the ground, such as an overhead power cable or a radio antenna tower, the field is
The sum of the incident field and the reflected field.
The early HEMP is the incident field. Figure 14a) shows the total field of the horizontal electric field at different heights in a good conductor plane (incident
The sum of the field and the reflection field); Figure 14b) shows the total field of the horizontal electric field at the same height for different soil conductivities. The definition of the angle
Refer to Figure 1.
a) different heights on the ground of good conductors
Figure 14 Horizontal electric field total field - sum of incident wave and ground reflected wave (early HEMP)
b) different soil conductivity
Figure 14 (continued)
Figure 15 shows the total horizontal electric field at different incident elevation angles when the height and soil conductivity are the same.
Figure 15 Total field of horizontal electric field - sum of incident field and reflected field when the incident wave elevation angle is different (early HEMP)
Figure 16a) and Figure 16b) correspond to the water when the early HEMP propagates underground, when the soil conductivity is different and the depth is different.
Flat electric field total field.
a) different soil conductivity
b) different depths
Figure 16 Horizontal electric field total field of early HEMP propagation in the underground
The above example is a good example of the effect of the ground on the incident electric field. When analyzing and experimenting with HEMP waveforms, you need to consider
Reflection and transmission of electromagnetic waves.
......
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.
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