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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.

The lightning represents a fundamental threat to the proper operation of aircraft systems. For aircraft protection, Electromagnetic Compatibility requires conductive structure that will provide among all, electromagnetic shielding and protection from HIRF and atmospheric electricity threat. The interaction of lightning with aircraft structure, and the coupling of induced energy with harnesses and systems inside the airframe, is a complex subject mainly for composite aircraft. The immunity of systems is governed by their susceptibility to radiated or conducted electromagnetic energy. The driving mechanism of such susceptibility to lightning energy is the exposure to the changing magnetic field inside the aircraft and IR voltage produced by the flow of current through the structural resistance of the aircraft. The amplitude of such magnetic field and IR voltage is related to the shielding effectiveness of the aircraft skin (wiremesh, composite conductivity).

The electromagnetic compatibility problem of the permanent magnet synchronous motor (PMSM) has become increasingly prominent with its continuous development to high power and high torque. To solve this problem, this paper adopts a method based on the establishment of body structure and windings of the PMSM to analyze its electromagnetic radiation (EMR). The radiation stimulus source is acquired by establishing the control model of the PMSM drive system under different driving conditions in Simulink and Carsim. The EMR model of the whole vehicle is established in FEKO by creating winding models and importing three-dimensional (3D) mesh models of the vehicle body and PMSM. The field circuit co-simulation and transmission line method are used in this paper. Finally, we can obtain the electric field radiation strength at different detection points under different driving conditions. The simulation results correspond with the EMR theory and electromagnetic shielding theory.

Regulations and Standards dealing with control of Electromagnetic Radiation have predictable effects on design, cost, complexity, performance and consumer acceptance of small, internal combustion engine-driven products. These effects, as they relate to the manufacturer, as well as to the consumer, the taxpayer, and the regulator, are discussed. Also considered is the need for EMR regulation, and whether imposing specific controls on all small IC engines, regardless of their applications and usage, will meet that need in the “real world.”

Electromagnetic shakers are an excellent choice for meeting the needs of active vibration control systems. They offer high fidelity performance coupled with ruggedness, high reliability, high efficiency and compact size. This paper describes a method of linear force generation using electromagnetics and its application to a particular type of moving armature shaker. The principal design considerations of this type of shaker system are discussed, including the transducer features, selection of power amplifiers, force sensing and use of local feedback control. The technology is shown to be applicable to a wide range of shaker sizes rated from 225N (50 lbf) to 22kN (5000 lbf).

The need to design and produce reliable and properly functional electronics in vehicles in recent years has placed a high level of emphasis on testing for Electromagnetic Susceptibility (EMS) of vehicle electronics, both at the component and vehicle level. This has come about from the increased usage of complex vehicle electronics such as emission controls for engines, vehicle performance monitoring, and electronic transmission systems are just a small sampling of application for vehicle electronics. To design and to produce vehicle electronics that are not susceptible to the electromagnetic environment that the vehicle can encounter, an organized and structured test plan, test procedures and facilities must be established. This paper describes a comprehensive approach to effectively test, qualify and analyze the Electromagnetic Sysceptibility of vehicle electronics both at the component and vehicle level.

One of the key technologies in improving engine performance is flexible valve timing. New combustion systems such as Homogeneous Charge Compression Ignition (HCCI) can be realized by flexible valve operation. Usually the valve timing is determined only by engine crank angle and is not flexible. To overcome this problem, an electromagnetic actuator had been proposed. However, a conventional solenoid actuator always requires current and the efficiency is low. In this study, a new type of linear actuator that uses bias flux produced by a permanent magnet (PM) to reduce power consumption was proposed. First, a cylindrical actuator was developed. To achieve further power consumption reduction, miniaturization and high-speed drive, a seesaw type actuator was designed. An experimental setup was designed to confirm its characteristics. The results showed improved performance and a high possibility for practical use.

Current development activities on modern heavy-duty diesel engines are aimed primarily on reducing emissions and improving fuel consumption. This paper describes how the water pump, traditionally driven from the crankshaft through a mechanical link, can be enhanced to satisfy increased demands for coolant flow for new engine strategies and also save power by eliminating unnecessary operation. An electromagnetic 2-speed clutch, incorporated into the overall envelope of the water pump allows the engine control system to select the best pump speed for any given operational condition. The presented underlying principles, technical solutions and prototype experiences demonstrate the utility of this new component.

Electromagnetic (EMA) bonding of thermoplastics provides a simple, rapid and reliable assembly technique to produce structural, hermetic or high pressure seals on most thermoplastic materials. It employs the basic principles of induction heating by developing fusion temperature at the abutting interface of parts to be welded using a thermoplastic electromagnetic intertayer. The process is so versatile it can weld almost any thermoplastic, filled or unfilled, to itself plus certain dissimiliar thermoplastics and non-thermoplastic materials, such as paper to thermoplastics. The EMA process can easily weld engineering, high performance resins and such difficult-to-weld materials as polyolefins and nylons. Understanding the design criteria for the electromagnetic bonding is essential to the new product designer. It involves an understanding of the process itself, the work coil designs, and the joint designs.

With Increasing environmental concerns and high fuel prices, the automotive industry is shifting its focus to electric vehicles (EVs). Electric motor being the heart of an electric vehicle, faces a major design challenge to have optimum performance and structural strength at an affordable cost. Synchronous reluctance motor offers higher power density at low cost since the rotor is free from rare earth permanent magnets or field excitation. However, torque fluctuations and resulting vibrations are a major concern. This is amended by optimizing the end-barrier width and end-barrier orientation angle in the rotor so as to maximize the torque and minimize the ripple. Simulations are also performed with ferrite magnets assistance to achieve an enhanced torque output. In each case, a structural analysis is done to verify the mechanical strength and rotor deformation considering structural and electromagnetic forces. The analyses are performed using finite element simulations.

RENAULT aims to become the first full-line manufacturer putting to market zero-emission affordable electrical vehicles and is therefore developing 100 % electric powertrains. NVH problems related to electric machine design have nothing in common with those of gasoline or diesel engines: electric whistling is a high frequency harmonic phenomenon, easily detectable due to the low background noise of a non-thermal vehicle and mainly perceived as very unpleasant by the customer. Therefore we have developed a coupled numerical simulation between electromagnetic and structural models, making it possible to understand the influence of magnetic parts design on noise and vibration level. Impact of the spatial and time coherence between magnetic pressures and vibration modes of the motor will be explained. The novelty of our approach is to already take into account the whole powertrain structure radiation, including reducer and power supply boxes.

With increasing fuel demands and environmental issues, electric vehicles are more important in reaching a bearable solution. The driving motor is a vital component of electric vehicles defining the design of electric propulsion, and it has small volume, high efficiency with sufficient power for torque and speed with precise control. To ensure a satisfactory life span of the motor, temperature rise must be controlled within safe operating zone. The sizing parameters, design with magnetism, thermal and mechanical calculations are carried out for a 1016-Watt traction motor system. Effects of variation of torque and speed for the 1016-W Brushless Direct Current (BLDC) motor was performed. Power losses calculated included Winding, Stator & Rotor core losses of around 220Watt from the input power of 1236Watt. BLDC motor with air gap between cores and multi-rotational frames are selected for the above calculations.