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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.

Hybrid electric vehicles require careful dealing with EMC because in HEV's analog and digital circuitry coexist in the vehicle's enclosed environment. These lead to a requirement of advanced methods for the increased requirements for electromagnetic compatibility and analysis and reduction of EMI [1]. There are many methods to increase EMI resistance of a hybrid car's electronics systems implemented printed circuit board, several of which will be reviewed in the current paper. In this review paper, we explain conducted and radiated emission avoidance methods using isolation amongst several subsystems. Within the harsh EM environment of a modern hybrid car, isolation between systems of differing frequencies is an effective method for reducing EMI/EMC issues. These techniques include usage of filters to hinder conducted emissions and shielding to stop radiated emissions.

With the advent of electronic controls and development of electromagnetically controlled fuel injection pumps, the cost of fuel systems using plunger-type pumps was substantially reduced. Further reduction in cost can be achieved if fewer solenoid valves are used. A new type of injection pump combining electromagnetic spill control principle with distributor-type operation is described. Only one solenoid valve is required for a multi-cylinder engine. The pump was designed for port injection of gasoline, but with some modifications could be adapted to direct fuel injection. The fuel injection system includes a controller capable of electronic trimming of port-to-port fuel distribution for tight control of air to fuel ratios in all engine cylinders. A review of the basic concept and operating principles is given, and test results as well as cost considerations are discussed.

Electric motors and generators produce vibrations and noise associated with many physical mechanisms. In this study, we look at the vibrations and noise produced by the transient electromagnetic forces on the stator of a permanent magnet motor. In the first stage, electromagnetic simulation is carried out to calculate the forces per tooth segment of the stator. The harmonic orders of the electromagnetic forces are then calculated using Fourier analysis, and forces are mapped to the mechanical harmonic analysis of the second stage. As a third stage, the vibrations of the structure are used to drive the boundary of acoustic domain to predict the noise. Finally, optimization studies are made over the complete system to improve the motor design and reduce noise. A simulation environment (ANSYS Workbench) is used to integrate a seamless workflow.

A new type ECCVT system is studied. It consists of a rotor and a stator with iron winding, an additive magnetic field adjusting winding, a cup-type rotor with special magnetic pole, inductive slip rings and power electronic controller. Its specialty is that the traditional electric transmission and electromagnetism coincidence are combined and the electricity is transferred unosculantly, so that the power split is realized. The new system also puts up a compact topology, good control and stability by the way of frequency conversion and magnetic field adjusting. The system not only has a wide continuously variable range as the traditional Electric Motor, but also has a high efficiency. Being used on a car, the clutch and starter are omitted. It also can be used as the driving line of the HEV.

These days, the use of virtual Multiphysics simulations through finite element analysis methodology is increasing exponentially during the development phase of automotive products. Thereupon, the automotive industries are becoming competent enough to build an ingenious and creative design with optimal performance within the coherent time. A huge number of electromagnetic as well as mechanical forces are being generated inside the Motor, when it is undergoing extreme driving conditions of the application. Hence it becomes vital to reduce the risks, if any, during the development phase by providing an optimal factor of safety within the electromechanical system of the motor. The present study gives details about conducted finite element analysis on an automotive traction motor to determine its mechanical strength and behavior. This study also focuses on finding the structurally critical regions over the motor assembly through electromechanical (Multiphysics) simulations.

The University of Texas Center for Electromechanics (UT-CEM) has been developing active suspension technology for off-road and on-road vehicles since 1993. The UT-CEM approach employs fully controlled electromechanical (EM) actuators to control vehicle dynamics and passive springs to efficiently support vehicle static weight. The program has completed three phases (full scale proof-of-principle demonstration on a quarter-car test rig; algorithm development on a four-corner test rig; and advanced EM linear actuator development) and is engaged in a full vehicle demonstration phase. Two full vehicle demonstrations are in progress: an off-road demonstration on a high mobility multiwheeled vehicle (HMMWV) and an on-road demonstration on a transit bus. HMMWV test results are indicating significant reductions in vehicle sprung mass accelerations with simultaneous increases in cross-country speed when compared to conventional passive suspension systems.

The actual development and test of electromechanical actuation hardware for critical, manned aircraft, flight control application that is specifically designed to interface with fly-by-wire commands is now represented by only two hardware units. One of these units was built by Delco Electronics for NASA-Houston and the second unit built by AiResearch Manufacturing Company for the Air Force Flight Dynamics Laboratory. Each of these units feature inside-out motor designs using rare earth samarium cobalt permanent magnet rotors with electronic commutation and are powered with 270 volt DC electrical power. The innovative design features, incorporated in these two actuation units, are thought to have a significance for the future that will eventually influence actuation design for business aircraft.

For aircraft electromechanical actuator (EMA) cooling applications using forced air produced by axial fans, the main objective in fan design is to generate high static pressure head, high volumetric flow rate, and high efficiency over a wide operating range of rotational speed (1x∼3x) and ambient pressure (0.2∼1 atm). In this paper, a fan design based on a fan diameter of 86 mm, fan depth (thickness) of 25.4 mm, and hub diameter of 48 mm is presented. The blade setting angle and the chord lengths at the leading and trailing edges are varied in their suitable ranges to determine the optimal blade profiles. The fan static pressure head, volumetric flow rate, and flow velocity are calculated at various ambient pressures and rotational speeds. The optimal blade design in terms of maximum total-to-total pressure ratio and efficiency at the design point is obtained via CFD simulation. A 5-blade configuration yields the best performance in terms of efficiency and total pressure ratio.

The aircraft electromechanical actuator (EMA) cooling fan is a critical component because an EMA failure caused by overheating could lead to a catastrophic failure in aircraft. Fault tree analysis (FTA) is used to access the failure probability of EMA fans with the goal of improving their mean time to failure (MTTF) from ∼O(5×104) to ∼ O(2.5×109) hours without incurring heavy weight penalty and high cost. The dual-winding and dual-bearing approaches are analyzed and a contra rotating dual-fan design is proposed. Fan motors are assumed to be brushless direct current (BLDC) motors. To have a full understanding of fan reliability, all possible failure mechanisms and failure modes are taken into account. After summarizing the possible failure causes and failure modes of BLDC fans by focusing on each failure mechanism, the life expectancy of fan ball bearings based on a major failure mechanism of lubricant deterioration is calculated and compared to that provided in the literature.