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The Abstracts AMEREM 2018 EMC on Large Aircrafts: Computer Simulations to Assist a Full Scale Experiment The Abstracts AMEREM 2018 EMC on Large Aircrafts: Computer Simulations to Assist a Full Scale Experiment Jean-Pierre Adam, Stéphane Vauchamp CEA, DAM, GRAMAT, F-46500 Gramat, France [email protected] Abstract — This paper presents the importance of The latter configuration required a large amount of computer simulations for an EMC experiment applied on computer resources. The mesh has to be fine enough to large aircrafts. An FDTD simulation tool has been used to accurately simulate the highest frequencies. A total of assist the design of the illumination system and to define about 6 billion of cells were needed. An example of output how it could be used. is presented in Fig. 3. Keywords — EMC, aircraft, FDTD simulation. I. INTRODUCTION The system presented here is very similar to the Artemis facility presented in Ref. [1]. It meets the same requirement: estimate the EMC coupling of large structures to assess the environment of critical components located inside those structures. The elongated shapes of the fuselage and the wings of an airliner may significantly resonate at the lower frequencies of the spectrum, but Figure 2. FDTD model including inner structures, materials, antennas, mainly for a horizontally polarized illumination. However, doors and cables. the Artemis facility is limited to vertical polarization. That is why a new illumination system with a horizontal polarization was needed. II. ILLUMINATION SYSTEM As shown on Fig. 1, the illumination system uses two very common antennas. These antennas have been simulated with the Gorf3D solver, based on the Finite-Difference Time-Domain Method (FDTD). Figure 3. E field map at 5 m above the ground for the entire experiment where the aircraft is located at 80 m from the illumination system. IV. CONCLUSION Figure 1. Illumination system, a log-periodic array antenna (30 MHz – 500 MHz) below an inverted V antenna (1MHz - 30 MHz). The computer simulation of an entire EM coupling III. SIMULATION OF THE ENTIRE experiment including the illumination system and the EXPERIMENT target was possible thanks to the increase of computational power and to the improvement of software functionalities. A test model of a particular jet has been deduced from This could be very helpful for the design and the post- publicly available data, common aircraft communication processing (for example Ref. [2]) of an EMC study applied antennas and reasonable assumptions on cables paths and on large aircrafts in a short timeframe. on doors joins. Fig. 2 presents the final FDTD meshed model. Two configurations have been simulated: first a REFERENCES [1] J.-P. Percaille, E. Kerhervé, I. Pouget, “EMP Coupling on plane wave illumination in free space which is the desired Large Structures”, Book of abstracts, EUROEM 2004, July 2004. result, second the actual illumination system on the ground [2] G. Eriksson, H.-J. Asander, “FDTD Simulations Used to which is the measurable configuration. Correct for Ground Effects During Aircraft Illumination Tests”, ______________________________________ IEEE International Symposium on Electromagnetic This study has been carried out for the DGA. Compatibility, 1999. Modelling of a Current Injection Source for the Susceptibility Study of Electronic Equipment G. MEJECAZE, F. PUYBARET, L. LABARBE T. DUBOIS, J-M. VINASSA CEA, DAM IMS Laboratory, CNRS UMR 5218 CEA-Gramat Bordeaux University F-46500 Gramat, France 33405 Talence, France [email protected] input were recorded, corrected by the transfer function of Abstract —This article deals with the modelling of a high the measurement chain and then converted into the amplitude current injection source associated with its frequency domain. In parallel, impedances Z 30 and Z 120 of electrical generation-transformation-distribution chain. these loads are measured with a network analyzer. Currents This complex installation has been modelled in differential and impedances measurements permit to calculate V and injection mode, validated and integrated in PSpice co Zs with (1) and (2) in frequency domain. software. This PSpice model has also been validated and is very useful in order to predict currents and voltages on = (1) switch-mode power supplies when a disturbance is injected in conducted mode at its input. (2) = Keywords-IEMI; modelling; current injection source. I. INTRODUCTION IV. APPLICATION AND SIMULATION Several studies show that a voltage pulse of several The calculated equivalent Thevenin generator has been kilovolts amplitude and a few hundred nanoseconds integrated into PSpice and used to predict the correct duration would be able to destroy many consumer or disturbing input current injected on a flyback switch-mode industrial equipments [1]. In this context, a Current power supply. To obtain this generator in PSpice, the Vco Injection Platform (PIC) has been designed to reproduce (in time domain) has been directly integrated and an this type of pulse. The aim of this article is to present the equivalent electrical circuit has been defined for the Zs. PIC modelling by an equivalent Thevenin generator. In a Fig. 1 presents the comparison between measured and first part, the PIC is presented. The second part presents the simulated disturbing currents injected at the input of the calculated equivalent Thevenin generator. In the third part, flyback which is conclusive. The small differences are due this Thevenin generator PSpice model is validated. This to the Z approximation. study has been carried out for Direction Générale de s l’Armement (DGA). II. PRESENTATION OF THE PIC The PIC gives the possibility to reproduce “high amplitude” electrical stresses representative of disturbances induced by the coupling of an electromagnetic field on long-distance wire links. The generated conducted signal is a bi- exponential type configurable in shape (rise time and mid- Figure 1. Comparison between measured input current and height time) and level, several hundred amperes. An simulated input current for the flyback power supply. electrical generation-transformation-distribution network including a generator, a step-up and a step-down V. CONLUSION transformer permits to power the equipment under test independently from the mains and to be representative of a This article described the equivalent Thevenin generator of conventional high voltage / low voltage distribution. a high power pulse source dedicated to injection on III. EQUIVALENT THEVENIN GENERATOR electronic systems. This model has been integrated into PSpice software and will be used to understand and predict The whole current injection source has been modelled with the behavior of power supplies when a high-power current pulse is injected at its input. an equivalent Thevenin generator in order to be integrated in PSpice simulation. To calculate the equivalent Thevenin REFERENCES generator (V co : open-circuit voltage and Zs: source impedance) in differential mode, injections were made on a [1] Y. V. Parfenov, L. N. Zdoukhov, W. A. Radasky and M. load of 30 Ω, then on a load of 120 Ω. The time Ianoz, “Conducted IEMI threats for commercial buildings,” IEEE Transactions on Electromagnetic Compatibility, vol. 46, no. 3, measurements I30 and I 120 of the related currents in load pp. 404-411, August 2004. Investigating HPEM effects on GaAs p-HEMT low- noise amplifier M. Girard, P. Hoffmann T. Dubois, G. Duchamp CEA, DAM Univ. Bordeaux CEA-Gramat IMS Laboratory, CNRS UMR 5218 F-46500 Gramat, France Bordeaux, France Abstract— This paper presents a study of HPEM (High III. RESULTS AND DISCUSSION Power Electromagnetics) effects on a GaAs e-PHEMT low noise amplifier (LNA). The study aims to evaluate HPEM A. Destruction of GaAs active element coupling effects on the LNA’s active element. The presented results include measurement of the LNA Destruction of the LNA’s active element was destruction threshold, as well as its response below observed for an input power of 46.5 dBm (45 W) (carrier destruction level. average power). No recovery of the DUT functionality is possible afterwards without replacing the active element. Keywords-HPEM; IEMI; LNA; GaAs; HEMT; pHEMT The destruction mechanism was further investigated. I. INTRODUCTION B. Degradation of the DUT’s functionality Studying the effects of IEMI is an important issue Progressive “degradation” of the DUT S-parameters in the EMC community [1]. Also, increase in availability was observed before destruction. Recovery is possible and and portability of IEMI sources was reported [2]. This has been observed. Further investigation is required to study focuses on irreversible and reversible effects of explain this phenomenon. Carrier trapping is most likely. IEMI on a low-noise amplifier (LNA). The LNA is the first active element of most RF receiving front-ends, and is therefore most likely to fail due to IEMI front-door coupling. II. DEVICE UNDER TEST The device under test is a low noise amplifier specifically designed for conducted high power interference studies. Its operating bandwidth is roughly 800 to 2000 MHz with 12 to 20 dB gain depending on the designated operating frequency. Figure 2. S22 parameter absolute value after each pulse. The value increases with higher values of Pin. The top- III. EXPERIMENTAL SETUP most curve corresponds to the last incremented value of Pin before destruction. The setup is close to the usual Direct Power IV. CONCLUSION Injection (DPI) method. It allows the monitoring of the DUT time domain response to HPEM pulses and The experiments presented in this paper show how frequency domain characterization through S-parameters transistor-scaled overvoltage effects can have an impact on measurement. circuit-wide functionality. Noticeable effects of exposure The waveform used was a 100 ns rectangular pulse to an HPEM environment can appear, even for non- modulated carrier at 1.575 GHz. destructive power levels. The aim was to measure its “destruction threshold”, which is the carrier average power (“Pin”) for which a REFERENCES single pulse causes irreversible loss of the LNA functionality. [1] W. Radasky, “Introduction to the Special Issue on HPEM and _____________________________________ IEMI”, IEEE Trans. On Electromagnetic Compatibility, vol.
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