HPEM (high power electromagnetic) threats and immunity ...

1 Montena technology saRoute de Montena 89 1728 Rossens Switzerland Tel. +41 26 411 84 84 Fax +41 26 411 17 (high power electromagnetic) threats and immunity test methodsNicolas Mora, Werner HirschiSeptember 5 2016 Natural <-> man made HPEM threatsNatural Lightning strikes Geomagnetic storms Electrostatic discharges Man made nuclear Electromagnetic pulse (NEMP) Non nuclear EMP : narrowband and wide band electromagnetics sources2 Lightning strikesDirect or indirect lightningThreat regarding to helicopters, airplanes, infrastructure, electronic equipment, missiles, ammunition,..3 Geomagnetic stormsCaused by a solar wind shock wave and/or cloud of magnetic field which interacts with the earth s magnetic fieldInduces high currents on long lines (hundreds of A)4 ESD5 Charging by air friction of rotor blades and airfoils ion emission from the engine charged particles in air (rain, snow, dust)Voltage: up to 300 kVMan made electromagnetic threats6 HEMPN arrowbandSource: IEC 61000-2-13 WidebandMan made electromagnetic threatsIdentified threats7 Source: IEC 61000-4-36 Man made electromagnetic threatsExamples of man made HPEM sources8 Source.

2 IEC 61000-4-36 HyperbandMesobandHypobandMan made electromagnetic threatsHyperband9 Source: IEC 61000-4-36 HyperbandMesobandHypobandMan made electromagnetic threatsMesoband10 Source: IEC 61000-4-36 Man made electromagnetic threatsHypoband11 Source: IEC 61000-4-36 Example of narrowband HPEM source 12 Source: Flux Compression Generator(FCG)13 Generated current: several tens of Mega-Amps Virtual cathode radiator(Vircator)14 Source for high voltage pulsesCathodeAnodeVirtual cathodeElectro-magneticwaveDielectricmat erialResonant cavity under vacuumVircatorExampleof HPM test setup usinga vircator15 Source: Montena -Armasuisse, SwitzerlandExamplesof UWB sourcesPortable UWB sources16 Source: Diehl, GermanyHigh power UWB sourceHigh voltage (kV to MV) pulses with very short rise time (some hundreds of ps)171 MV / ~ 200 psrise Radiated Field : ~ 62 kV/m at 85 mNew ideas18 NATO car device vows to stop suicide bombers, available in test systemFast pulser + HIRA antenna1930 kV / ~ 100 psrise timeRadiated Field.

3 < 1 kV/m at 50 mTypicalUWB test system20 TypicalUWB test system21 nuclear Electromagnetic Pulse (NEMP)22 Explosion in an altitude of several hundreds of kmGamma ray impulseCompton effect in the stratosphere (and other effects)Emission of an electromagnetic pulseIrradiation of an area with a diameter of several hundreds of km on earthThe pulse emission can be divided in: Earlytime: fastrisetime / high amplitude / lowenergy Intermediatetime: moderaterisetime / amplitude / energy Latetime: slow pulse / lowamplitude / high energyTypicalmeasuredNEMPNEMP phenomena23EM pulse definition as per standardPulses definition according to IEC 61000-2-924 Coupling on systems / sub-systems25 Pulse typeStandardized Waveform(MIL-STD)Subsystem or deviceShort line1 10 mMiddle line10 m 10 kmVery long line10 5 000 kmEnclosureLinesEarly time(nanosecondrange)2 / 23 ns or 20 / 550 nsEffectEffectEffectEffectIntermediate time(microsecondrange) s / 5 msNo effectNo effectEffectEffectLate time(secondsrange) / 25 sNo effectNo effectNo effectEffectNEMP effect on equipmentCoupling on lines (and antennas)

4 Coupling on enclosures26 Subsystems or stand alone systemsTypical standalone systems and subsystemsSystem directly exposed to EMP threatRadiated susceptibility of the subsystem to E1 pulse27 Radiated susceptibility test RS105 Test at threat level in a NEMP simulatorMIL STD 461, RS105 FastE-fieldpulse Rise time : ns Duration : 23 ns Intensity: 50kV/mTest all orthogonal polarisations At least 5 pulses28 Radiated susceptibility test RS105 Example of NEMP test system as proposed in MIL STD 46129 Radiated susceptibility test RS105 Typical NEMP simulator for subsystem tests30 high RS105 test system with a 230kV pulse generatorinstalled on an open area test siteDistributed Termination loadHV generatorRadiating lineGround planeDerivative field sensorRadiated susceptibility test RS105 Typical NEMP simulator for subsystem tests31 indoor high RS105 test system with a 170kV pulse m high radiation line Approx.

5 EUT size: 5 x x 3 m (L x W x H)Indoor or outdoor installationMobile NEMP simulator ( m) mUp and ready in less than 3 hRadiated susceptibility test RS105 Example of larger NEMP simulator system level tests33 9 m high RS105 test system with a 800kV pulse generatorElectromagnetic field pulse propagation34 What about cables?35 What about cables?Split the test in two parts : Radiated susceptibility tests Conducted susceptibility testsIntrasiteand intersitecables couple with E1, E2 (and E3)Protections are installed at each electrical entry point and shall be tested according to MIL STD 188-125, appendix 2 : Pulse Current Injection36 MIL STD 188-125, PCI37 MIL STD 188-125, PCIP ulse definition and injections levels38 MIL STD 188-125, PCIA cceptable residual current levels39 MIL STD 188-125, PCIA cceptable residual current levelsMIL STD 461, CS116 to test the equipment40 MIL STD 188-125, PCIE xample of needed test equipment41 Short pulse generator 1 5 kA Short pulse generator kA Intermediate pulse generator Charge line pulser Coupling devicesE3 test for intersitecables?

6 Example of test setup for E342E3 test for intersitecables?Very expensive testOnly affects long lines -> high voltage power approach with modelling and be considered together with power grid switching issues and possibly geomagnetic storms of large systemsOn goingprojectfor a 25m high, 140m long NEMP simulatorwitha 2MV pulse generatorTest of large systemsBuild very large EMP simulator ! ?45 Trestle in the USA : largest ever built EMP simulatorTest of large systemsUsually impossible to test whole system at threat level Test at lower level Measure currentsand field on each sub system Interpolate to getthreat level for each subsystem Test each subsystemaccordingly46 Test of fix systemsBring the simulator to the test site !

7 ?47 MEMPS : 25 m high mobile EMP simulatorTest of fix systemsUsually impossible to expose fix equipment of system to EMP threatPerform CW shielding effectiveness PCI for electrical entry pointsValidate with a CWI (continuous wave immersion) test in frequency domain48 CWI testTest setup as proposed in MIL-STD 188-125 49 CWI the EUT at levelmeasuredby the referencesensor: Filluminating(jw) the fields, currents or voltages inside the shelter : Finternal(jw) the transfer function : A(jw) = Finternal(jw)/Filluminating(jw) analytical form of total field HEMP excitation : Fthreat(jw) with the transfer function to get the inside threat : S(jw) = A(jw)*Fthreat(jw) the threat in time domain using inverse FFT : s(t) 50 Non nuclear EMP : already a factIn spring 2003, stories leaked to the press suggested that the Pentagon, after decades of research, had finally deployed such a device in Iraq.

8 And when news footage showed a bomb destroying an Iraqi TV station, many informed onlookers suspected it was an electromagnetic e-bomb. 51 Non nuclear EMP : already a fact52 Already a factPublic literature has reported criminal usages of electromagnetic Japan, criminals used an EM disruptor to interfere with the computer of a gaming machine and falsely triggered a win. Kizlyar, Dagestan, Chechen rebel command disabled police radio communication using RF jammers during a St. Petersburg, a criminal used an EM disruptor to disable a security system of a jeweller store. The reports mentioned that building the EM disruptor posed a technological challenge similar to assemble a home microwave multiple European cities ( Berlin) criminals used GSM-Jammers to disable the security system of London, UK, a city bank was the target of a blackmail attempt whereby the use of EM disruptors was threatened to be used against the banks Russia, Chechen rebels used an EM disruptor to defeat a security system and gain access to a controlled the Netherlands an individual disrupted a local bank IT network because he was refused loan.

9 He constructed a briefcase-size EM disruptor, which he learned how to build from the internet. Bank officials did not realize that they had been attacked or what had caused the disruption until the assailant was Moscow, the normal work of one automatic telephone exchange station has been stopped as a result of remote injection of a voltage in to a telephone line. As a result two hundred thousand people had no phone connection for one day53 Source: assessment to HPEM of subsystems or mobile small-medium size systems is quite simpleAssessment of large systems against HPEM requires : An system analysis and identification of each subsystem An specification of the threat level for each subsystem (by analysis, CWI or low level exposure) An assessment of the susceptibility of each subsystem at specified exposure you for your attention !

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