David Baudry

Applications of the Near-Field Techniques in EMC Investigations

A completely automatic near-field mapping system has been developed within the Research Institute for Electronic Embedded Systems (IRSEEM) in order to determine the electromagnetic field created by electronic systems and components. This test bench uses a 3-D positioning system of the probe to make accurate measurements. This paper presents some applications of the near-field techniques in EMC investigations. In the first part, near-field measurements are used to locate precisely the electromagnetic sources of a limiter device. In the second part, we present an equivalent model of the radiated emission of an integrated circuit. In the last part, the near-field test bench is used to characterize faults in a cable.

Near-field techniques for detecting EMI sources

A completely automatic near-field mapping system has been developed within IRSEEM (French research institute for electronic embedded systems) in order to determine the electric field radiated by electronic systems. This test bench uses a 3D probe positioning system to make accurate measurements. The paper presents a validation of the test bench on a microstrip line and experimental results realized on a diode limiter function.

Postprocessing of Near-Field Measurement Based on Neural Networks

This paper presents postprocessing based on neural network (NN) models to reconstruct the magnetic near-field profile with an improved spatial resolution for one or different frequencies. The models aim at decreasing the time required to perform near-field electromagnetic compatibility (EMC) measurements. The multilayer perceptron (MLP) NNs are used to determine the magnetic near field radiated by passive devices and power electronics components. An optimization method, called the split-sample method, is implemented to determine the structures of the NN. The results obtained with the proposed method are compared with the measurement results. A graphic interface (GUI) is created to simplify the utilization of the developed NN models.

Near-field coupling model between electronic systems and a transmission line

This paper presents an analysis of radiated electromagnetic disturbances between electronic devices (parasitic emission source) and a transmission line. The study aims to model the coupling and for this purpose, two concepts are combined: the emission source is modelled by an array of elementary dipoles (electric and magnetic) and the induced voltage in the transmission line is calculated from the equivalent sources radiation by two different approaches. The first one is totally analytical and is based on the transmission line theory and Taylor model. The second one uses the insertion of equivalent sources into an electromagnetic simulation tool. To validate our model we apply it for two cases: a passive system and an active one disturbing a transmission line.

A Framework for Improving the Sharing of Manufacturing Knowledge through Micro-Blogging

The purpose of this paper is to report on an industrial investigation, conducted within a leading power generation manufacturer, to better understand the organisational processes and challenges present in relation to the management and sharing of knowledge during product manufacturing. Findings reveal that the organisation is failing to fully benefit from web 2.0 technologies and particularly micro-blogging. Details of the investigation results are presented and a conceptual framework is proposed to demonstrate how organisations may enhance the sharing of explicit manufacturing knowledge using micro-blogging tools.

Near-field investigation of the radiated susceptibility of printed circuit boards

This paper aims at studying the near-field coupling between PCB and electromagnetic waves by using the transmission line theory. We present a model of coupling between a non-uniform electromagnetic field and a printed circuit board with an analytical resolution in the frequency domain. A first validation is made by using a plane wave excitation. In a second step, we study the coupling between a non uniform wave and a printed circuit board (PCB) in near field.

Modeling radiation sources of electronic components

Taking into account the integration of electronic components on the boards, the consideration of electromagnetic perturbations is more and more important. The aim of this paper is to present a methodology to model the electromagnetic radiation of electronic components or complete systems so as to predict and avoid future possible interferences. As application, two different systems are modeled: a microcontroller and an oscillator. The characterization of the oscillator allows us to validate the model at a high distance from the component. So, the magnetic field is simulated at 5cm over the circuit under test and it is compared to the measurements. Due to the increase of embedded electronic circuits present in the systems, modeling the emissions of electronic components has become important in the last years. The prediction of possible malfunctions caused by the interference between components mounted on the same board can be achieved by simulation. Consequently, the electronic board designers need the models of their components to predict the radiation and the possible interferences before the conception of the board. In this paper, a simple technique of modeling the magnetic field radiated by a component is presented. The component is modeled by an array of dipoles disposed in a two-dimensional plane. Some characteristics of these dipoles are fixed by the user; nevertheless this particularity provides simplicity for the process and consequently, velocity in the resolution of the equations. In order to apply the model to a real component, a microcontroller mounted on an autonomous board is used. Due to the fact that the measurements of the emissions at a certain height over the component are needed, the main difficulty of using this active device lies in the measurement of the phase of the magnetic field. The technique used is also presented. Due to the fact that the microcontroller used is mounted on an electronic board, the verification of the model at another distance high enough cannot be done because the radiation of the elements around it is measured. Therefore, another circuit is used: an oscillator. This circuit is modeled and afterwards the magnetic field at 5cm is simulated and compared with the measurements. II. PRESENTATION OF THE MODEL

Impact of spare parts remanufacturing on the operation and maintenance performance of offshore wind turbines: a multi-agent approach

Offshore wind farms are a growing source of energy, which aims to ensure a clean energy with a low environmental impact. In this context, this paper investigates opportunities of the turbine gearbox end of life-cycle to improve the operation and maintenance strategies. We determine the impact of spare part policy based on the remanufacturing of gearboxes recovered after each replacement. The remanufacturing implementation allows the extension of the gearbox life-cycle and involves a perfect organization and coordination between maintenance, monitoring, operation and spare part supply chain to determine the best way to use each gearbox of each wind turbine. In this paper, we present a multi-agent based approach to analyze the impact of the spare parts remanufacturing strategy on the performance of an offshore wind farm in term of total cost and carbon footprint.

Experimental Investigation on the Power Electronic Transistor Parameters Influence to the Near-Field Radiation for the EMC Applications

With the increases of the module integration density and complexity in electrical and power electronic systems, serious problems related to electromagnetic interference (EMI) and electromagnetic compatibility (EMC) can occur. For the safety, these disturbing efiects must be considered during the electronic equipment design process. One of the concerns on EMC problems is induced by unintentional near-fleld (NF) radiations. The modeling and measurement of EM NF radiations is one of the bottlenecks which must be overcome by electronic engineers. To predict the unwanted difierent misbehaviors caused by the EM radiation, NF test benches for the reconstitution of scanning maps at some millimeters of electrical/electronic circuits under test were developed at the IRSEEM laboratory. Due to the di-culty of the design with commercial simulators, the prediction of EM NF emitted by active electronic systems which are usually based on the use of transistors necessitates more relevant and reliable analysis techniques. For this reason, the main focus of this article is on the experimental analysis of EM NF radiated by an MOSFET transistor with changing electrical parameters. Descriptions of the experimental test bench for the EM map scan of transistors radiation are provided. This experimental setup allows not only to detect the EM NF emission but also to analyze the in∞uence of the excitation signal parameters

Augmented Industrial Maintenance (AIM): A Case Study for Evaluating and Comparing with Paper and Video Media Supports

Maintenance is a crucial point to improve productivity in industry whereas systems to be maintained have an increasing complexity. Augmented Reality (AR) can reduce maintenance process time and improve quality by giving virtual information and assistance to the operator during the procedure. In this paper, a workflow is firstly presented allowing a maintenance expert to author augmented reality maintenance procedures without computer skills. Then the AR maintenance application developed is described. Based on it, we present a case study which aims to compare maintenance efficiency with respect to the market available media support used, i.e. paper, video, AR tablet or AR Smart Glasses. A set of experiments involving 24 persons is described and analyzed. The results show that augmented reality maintenance reduce number of errors done by operator than with paper for the same duration of maintenance. A qualitative analysis shows that AR systems are well accepted by the users.