Charles JullienSafran Electrical and Power · R&T Department
Charles Jullien
PhD
Modeling/Measurement electromagnetic coupling in aeronautical harness and over shielding harnesses
About
32
Publications
12,253
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108
Citations
Citations since 2017
Introduction
Skills and Expertise
Additional affiliations
December 2012 - present
Safran Electrical & Power
Position
- Engineer
Description
- Since July 2015, Expert society in harness model for EMC
November 2009 - December 2012
Education
October 2009 - December 2012
September 2007 - September 2009
September 2004 - September 2007
Publications
Publications (32)
The number of electrical and electronic equipment on board aircraft and their associated connections and supplies has massively increased over the last 20 years. In order to optimize the mass of these systems and to ensure more efficient control and command services, new voltage supplies have emerged in aircraft electrical systems, such as the HVDC...
The last twenty years have brought a tremendous amount of progress in all fields, aeronautics included. The quest for better, faster, more connected but also more reliable aircrafts and on-board options, has generated amongst others, a very constraining electromagnetic environment, in which electric and electronic equipment have to function properl...
Harness EMC design becomes more and more complex due to higher cable density, more diverse signals, and newer test requirements. An electrical wiring interconnection system (EWIS) can be protected either by shielding or by separating. EMC optimization of the supply chain is a solution to the general EMC optimization of an aircraft. However, every n...
This P2855 standard provides recommended measurement techniques for evaluating, and methods for specifying, the capabilities or effectiveness of shielding on cable/connector assemblies for the control of Electromagnetic Interference (EMI) to allow product compliance to common Government and regulatory standards, and for achieving system Electromagn...
Experiments and demonstrations (E&Ds) have always been a very special part of the EMC and Signal Integrity/Power Integrity (EMC+SIPI) symposia - and for a good reason. Within the broad range of technical presentations, workshops and tutorials, practical demonstrations deliver the unique opportunity to experience the variety of hands-on hardware and...
This article presents the aeronautical vision for electrical power transportation with a short-term vision. A global analyze of electrical energy on board will be done during the discussion on problematics introduce by hybridization in aeronautical domain. A focus dedicate to harnesses will be presented. This will highlight the importance and consi...
Cet article traite de la modélisation de la détection des défauts non-francs à l’aide de la topologie électromagnétique appliquée aux lignes de transmission et de la MCTDR pour des câbles couramment utilisés dans l’aéronautique. En effet, avec l’augmentation des équipements électroniques à bord des aéronefs, de plus en plus de câbles sont présents...
Due to the large amount of electrical equipment aboard modern aircraft, several EMC problems appear which can be tackled by filtering disturbances at the equipment inputs and shielding cable links (braiding, covering, over-braiding). Among the others, the segregation between interfering cables or bundles of cables becomes crucial to ensure that cou...
Modern aircraft hosts a large number of electric systems. Due to the transition to a More Electrical Aircraft, future platforms will use even more electric systems. This increases the complexity of the EWIS design from an EMC point of view. When possible, segregation between potentially interfering cables or bundles is a convenient solution to avoi...
Segregation rules are one of the three solutions to overcome EMC problems together with filtering of disturbances at the equipment inputs and shielding of cable links (braiding, covering, over-braiding, etc.). These rules enable mass reduction in the selection of cables and optimal route definition in which compatible cables (having similar levels...
Shielding effectiveness is an important parameter for cable EMC. For shielding harnesses, the assessment of the shielding properties of cables at low frequencies is generally made through the determination of the transfer impedance (the transfer admittance being generally neglected). The large number of harnesses on an aircraft will significantly i...
This article presents a complete framework able to characterize the performances in both frequency and time domains of “vibrating intrinsic reverberation chambers” made of a metallized tent of shape continuously changing under the action of the stirring process. In the frequency domain, the analysis is based on a method proposed recently in order t...
In this paper, we focus on the problem to evaluate the performance of a cable harness for a complex aeronautical system. Indeed, the various studies carried out in recent years on the subjects of crosstalk and modelling of the power harnesses made it possible to put in place model bricks and tools of simulations. In addition, the measurement of the...
Dans cet article, nous nous concentrons sur le problème de l'évaluation de la performance d'un faisceau de câbles pour un système aéronautique complexe. En effet, les différentes études menées ces dernières années sur les thèmes de la diaphonie et de la modélisation des harnais en général ont permis de mettre en place des briques modèles et des out...
This letter presents a method to determine experimentally the transfer impedance of electrically short shielded cables up to 100 or 150 MHz (depending on the cable length). The proposed method aims to create a disturbance along the cable shield with a localized injection device as for instance a toroidal magnetic probe. Two different experimental s...
In this paper, we focus on the problem of evaluating the performance of a cable harness for a complex aeronautical system. Indeed, the various studies carried out in recent years on the subjects of crosstalk and modeling of the power harnesses made it possible to put in place of model bricks and tools of simulations. In addition, the measurement of...
The electrical links can be protected either by shielding, i.e. by placing a conductive screen that protects and limits the electromagnetic radiation and coupling, either by separating the links from the others with a certain distance in order to create a segregation between the signals and powers transmitted. The assembly in bundle or harness of c...
This article presents an experimental validation of a harness distributing the filtering function and making the connection between a converter and a motor. This harness is both designed to have a common mode of reduced capacity and reduced shielding. This allows both to reduce the common mode current and the strain on power electronics. This offer...
Ce document décrit un process permettant de valider une installation de harnais dans un aéronef pour la CEM d’un point de vue diaphonie inter et intra harnais. Un outil numérique a été développé et validé sur deux cas tests. Le premier concerne 2 harnais avec 3 câbles et le second concerne 15 harnais avec plus de 1400 liaisons. Ce travail permet de...
Ce document décrit une modélisation de câble trifilaire blindé dont les modèles varient par la forme que peut prendre le blindage. Par ailleurs, un outil permettant de modéliser ces géométries a été développé afin de le mettre en forme pour être compatible avec un outil de modélisation utilisant la théorie des lignes de transmission.
An analysis of new protective socks for extremities of twisted pair, from a predesign with numerical aspect and an experimental point of view to an experimental validation, is proposed. The numerical model is built as a succession of uniform transmission lines. Crosstalks between these twisted pair and single wire inside the bundle are measured and...
Cet article présente une validation expérimentale d'un harnais faisant la liaison entre un convertisseur et un moteur permettant de répartir la fonction de filtrage. Ce harnais est à la fois conçu pour présenter une capacité de mode commun réduite ainsi qu'un blindage allégé. Ceci permet à la fois de diminuer le courant de mode commun sur les phase...
An analysis of crosstalk inside a complex aeronautical bundle from an experimental and from a numerical point of view is proposed. The numerical model is built as a succession of uniform transmission lines generated randomly. Modeling of the geometrical pattern of twisted pairs is included. Crosstalks between these twisted pairs and single wires in...
This thesis focuses on the analysis and the modeling of electromagnetic interactions on aeronautical bundles made of multicore cables representative of the industrial reality. Indeed, technological changes (introduction of composite materials, increased electrical functions, ...) force to reconsider the requirement levels of electromagnetic couplin...
This paper deals with the modeling issue of the near-field coupling of an unshielded twisted-wire pair on a nearby single wire. It introduces a discussion about the appropriate modeling method for predicting the induced current on the victim wire and proposes a cost-effective approach to deal with either ideal or nonideal twisted pair. A nonideal t...
This paper focuses on the coupling between a twisted pair cable (TPC), which is modeled as a perfect helix of two conductors, a second TPC and a single wire. After a description of the simplified model, an experimental validation was carried out for perfectly symmetrical pairs and pairs with untwisted ends.
This paper focuses on the coupling between a twisted pair cable (TPC), which is modeled as a perfect helix of two conductors, and a single wire. The simulation of the current on a victim wire induced by a TPC made of a single twist gives non-obvious patterns depending on the starting angle of the TPC. An analytical model based on a circuit represen...
Dept. RTDSA (2) LABINAL Villemur sur tarn, FRANCE Isabelle Junqua (3) Dept. DEMR/CEM (3) ONERA Toulouse, FRANCE Abstract— To get closer to the reality of aeronautics wire harnesses, we propose to represent a bundle as a non-uniform transmission line by discretizing it into several sections. For each section, positions of conductors are randomized....
Projects
Project (1)
In the context of Electric Wiring Interconnection System (EWIS), the installation directives and specifications are generally provided by airframers to suppliers. They comply with recent certification specification and implicitly guarantee the reliability of the system. These specifications are coming from a long term experience in aeronautical industry. However, the applied good practice design and installation rules suffer from fast technological evolution in aeronautical industry (lightweight composite materials, generalization of electrification of functions on board aircraft, etc.) and industry evolution itself (development cycle, productivity, reduction of the number of physical prototypes, etc.).
These rules concern the allocation of cables in bundles (segregation in routes depending on criticity of electrical functions), the relative geometry of routes of bundles (spacing and height between routes...), the size of bundles, the cable function and loads. Those rules depend on the airframer and generally on the aircraft.
Controlling EWIS reliability in today aeronautical industry cannot be managed by good practice rules only. Aircraft industry needs reliable Tools and Methods for managing the wiring complexity of the wiring installed in new generation of aircraft.
In this context, the ANALYST’s objective is double.
In the first hand ANALYST aims at developing and validating electromagnetic (EM) numerical Tools and Methods for optimizing a very important installation concern: the minimum distance between bundles. This distance must guarantee the absence of EM susceptibility for an acceptable set of bundle parameters (constitution and geometry, crossing angle...). From a mathematical perspective, the distance must be determined with the highest possible level of confidence..
On the other hand, in some particular configurations, the minimum distance is not achievable because of the limited room available. It is then mandatory to derogate to this absolute parameter. ANALYST aims at evaluating the level of confidence associated with this derogated distance.
The minimum distance rule must be numerically evaluated on a generic configuration. In both situations, absolute and derogated, the minimum distance will be determined on a simple configuration of two straight bundles having the same length. Then the robustness of this rule will be evaluated on complex and realistic cable-bundles.
This project has received funding from the Clean Sky 2 Joint Undertaking under the European Union’s Horizon 2020 research and innovation programme under grant agreement No 821128
