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This paper describes a systematic decision making process applied to the field of Electromagnetic Compatibility of automotive vehicles. It identifies objectives and classifies them by priority. It describes various mechanizations of possible assurance methods. A matrix of alternate mechanizations and objectives which they meet is assembled and the best alternate is identified.

One of the challenges of automotive designs which utilize heat reflecting glazing is the conductivity of the reflective coating. Significant attenuation of electromagnetic energy occurs when devices which send or receive signal through the glazing are mounted on or very near heat reflecting windows. A number of methods are available to maintain electromagnetic compatibility and the function of these and other devices in the passenger compartment which communicate with devices outside of the vehicle.

As the volume and complexity of electronics increases in automobiles, so does the complexity of the electromagnetic relationship between systems. The reliability and functionality of electronic systems in automobiles can be affected by noise sources such as direct current (DC) motors. A typical automobile has 25 to 100+ DC motors performing different tasks. This paper investigates the noise environment due to DC motors found in automobiles and the requirements that automobile manufacturers impose to suppress RF electromagnetic noise and conducted transients.

Project Oculus, an experimental configurable sensor platform for deploying airborne sensors on a C-130 aircraft, is currently in its pre-flight testing phase. The electronics driving the platform are available commercially off the shelf (COTS) and as such are not automatically rated to comply with stringent military electromagnetic standards as defined in MIL-STD-461. These COTS electronics include efficient switching power converters, variable frequency motor drives (VFD), and microprocessor based equipment, all of which can present electromagnetic interference (EMI) issues. Even in a design where EMI issues were not considered up front, it is often possible to bring the overall configuration into compliance. Switching and digital clock signals produce both conducted and radiated noise emissions. Long cable runs and enclosure apertures become noise transmitting antennas. Large switching currents place noise on the power lines causing interference with other equipment.

Most electronic systems, including electric motor drives and electric power conditioners, require the use of electromagnetic devices, such as inductors and transformers as circuit components to carry out any of the following functions: a) Suppressing or isolating specific harmonic components in voltages and currents. b) Providing electrical isolation from one circuit to another. c) Limiting the currents under fault conditions. d) Increasing or decreasing the voltage or current levels. e) Integrating voltages, currents, or power. f) Providing neutral line, phase shift. The performance of the electronic systems is dependent upon the design of the electromagnetic components that are used. For the aerospace quality hardware, the weight, size, cost, reliability, and efficiency of the electronic systems are substantially dependent upon the design of electromagnetic components.

This paper discusses design and testing of a regulated dual voltage automotive electrical system that provides both 48 and 12 volt subsystems. The paper focuses on the design, performance, and manufacturing differences between 12 volt and 48 volt electromagnetic components for vehicle applications. Dual voltage systems have inherent benefits of lower current consumption, smaller/lighter wiring harnesses, and potential improvement in system efficiencies. These benefits help some automotive operations, but are not readily transferred to the electromagnetic product arena.

Insuring conducted Electromagnetic Compatibility (EMC) of electronic components from DC to 200 MHz can be determined through analytical prediction techniques and empirical data reduction. For analytical modeling and prediction of automotive electrical/electronic systems, there are two main analytical techniques which can be used. From DC to approximately 500 KHz, conventional circuit analysis lumped parameter networks are implemented. From 500 KHz to 200 MHz, transmission line theory using linear passive networks are employed.

In the sensitive automotive applications like the safety restraint systems (SRS), twisted lines can be used to link the components of the system because of their property of reduction of the electromagnetic interference (EMI) coupling. Compared to the parallel lines, the twisted lines present the drawback to consume more copper in their manufacturing due to the greater length of their conductors. A parametric study based on the numerical modeling and the measurement of twisted lines is conducted in order to analyze the effect of the twisting pitch and of the untwisted part of these lines on the level of EMI coupling. This study will enable to optimize these two parameters in order to reduce the level of EMI coupling as well as the length of the conductors of the lines.

The electromagnetic coupling between a conductor and a composite structure by wire-mesh techniques using method of moments is investigated. A three-bladed composite panel with an aluminum tube located above the panel is considered in this analysis. Computations are made of the current on the tube for various frequencies with height above the panel as a parameter. The numerical results compared reasonably well with the measurements. The technique proves to be useful in modeling the composite structures such as wings of an aircraft.

The electromagnetic dent removal process removes dents from many aluminum structures where access is either limited to one surface (e.g., bonded aluminum honeycomb parts) or where access to the rear surface is restricted by equipment or other structures.

In the past ten years, the all composite commercial aircraft has become a reality and the need for the aircraft designer to consider electromagnetic threats has also grown. Aircraft systems are now designed with miniaturized electronic components, which make them more sensitive to EMI; and it turns out that the safety of flight relies on the functionality of some of these systems. Composite materials (Polymer Matrix Composites, PMCs) are characterized by their low conductivity that greatly reduces the shielding effectiveness of the aircraft structure and consequently the protection of systems against HIRF, and mainly against lightning indirect effects.

The SAE, at the request of the FAA, established the AE4R Subcommittee for the purpose of evaluating the hazard to airborne electronic systems produced by the electromagnetic environment. This task involves determining the intensity of the electromagnetic environment, proper design procedures, and the establishment of test techniques. The task of panel one, the data accuracy panel, is to determine the level of the electromagnetic environment to which an aircraft could be exposed. A list of detailed assumptions was produced. These assumptions were applied to the known emitter population. Then, a set of histograms was derived which depicts the electromagnetic environment that an aircraft may experience under various conditions of operation.

By using tridimensional full-wave computer simulations three different scenarios involving antenna placement in an automobile model were analyzed. The electromagnetic impact of the vehicle model complexity was taken into account, as well as the relative position of the antenna on its roof. The simulations were run in a moderate equipped computer, and show a powerful alternative to complement and forecast real laboratory evaluations

This paper takes the single-phase full-bridge power converter of the power generation system of the free-piston engine of the incremental electric vehicle (EV) as the research object. By establishing the three-dimensional (3D) electromagnetic radiation simulation model of the power converter, the electromagnetic radiation field of the power converter is simulated and analyzed by using the equivalent excitation source method. The shielding and suppression effect of the power converter shell on the far-field radiated electromagnetic field and its influence on the internal electromagnetic field are analyzed. The shielding cover of the radiation source and sensitive source of the power converter is designed, and the effectiveness of the electromagnetic radiation shielding device for shielding the radiation source and sensitive source is discussed.

Currently, the drivers are able to control a door lock at a distant point from a vehicle. Recently, a door lock system has been developed to detect an owner approaching and to unlock the door when he/she touches the door handle. In this system, an antenna detects the existence of the owner with an electrical key near the vehicle. Since this detection performance of the antenna (directivity) varies in the operating area, it is essential to recognize directivity and confirm that there is unoperating area. In this report, we describe an example of predictive calculation on directivity of an antenna using the electromagnetic field analysis.

Electromagnetic forming (EMF) technology has been used lately for the joining and assembly of axisymmetric parts in the aerospace and automotive industries. A few case studies of compressive-type joining processes applied on both aluminum and titanium or stainless tubes for aerospace applications are presented. In the first case study, tests were conducted using 2024-T3 drawn tubes joined with a steel end fitting to form a torque tube using different forming variables including: the fitting geometry, material formability and forming power (KJ). The power setting and the fitting geometry were optimized to improve the fatigue life, torque off, and the axial load capability of the torque tube joints to drive the leading and trailing edge high-lift devices.

An electromagnetic fully flexible valve actuator (FFVA) for internal combustion engines is described which offers the potential for significant improvements in fuel economy, emissions, and performance, especially at low end torque, in internal combustion engines. The FFVA offers variable lift and timing combined with controllable seating velocity. It operates on a design principle distinct from existing actuators: the electromagnetic actuator exerts appreciable bidirectional force throughout the device stroke mitigating the need for mechanical spring-derived resonance. The FFVA is a direct drive device with a unique magnetic structure that combines high bandwidth and strong forces to meet the engine performance requirements. This paper presents the innovative electromagnetic design, simulation, and bench testing of the actuator on a single cylinder engine.

This paper discusses present electromagnetic interference (EMI) measurement techniques and some of the problems associated with EMI measurements, especially relative to automotive problems. Improved measurement techniques are then discussed, including: 1) use of isotropic probes capable of measuring unperturbed, complex fields close to their sources and 2) transverse electromagnetic transmission cells with expanded applications for both susceptibility and emission measurements. Finally, some suggestions for minimizing automotive EMI problems are given.

The last decade of research and development has led to tremendous increases in the complexity of electronic devices. It has also led to significant decreases in the size and power requirements of these devices. The combination of these has led to a vastly increased susceptibility potential of electronic products to electromagnetic interference (EMI). This potential has resulted in the requirement to develop small electromagnetic field sensors to assess the susceptibility of engineering prototypes to EMI. This paper presents an overview of the state-of-the-art technology in small electromagnetic field sensor systems, and provides an insight into ongoing research and new developments.

This paper defines the overall problem of electromotive interference (EMI) from an automotive viewpoint. First, the general conditions (coupling modes) that apply within the automobile are described, then the automobile as a source of interference is examined. Performance criteria for electromagnetic automobile radiation limits as defined by various organizations are compared. Methods of measuring EMI are discussed, then the authors examine the environment both inside and outside of the automobile. Finally, the paper presents detailed test results of automotive impedance studies.