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Power sources based on magnetic energy derived from superconductivity have been considered for commercial utility power, air and ground mobile power uses, and spacecraft applications [1]. The advent of high temperature superconductors has reduced one of the penalties of superconducting magnetic energy storage in that the refrigeration and cryocontainers become greatly simplified. Still, structural and current density issues that limit the energy density and size of the superconducting inductors do not change. This paper covers basic principles of magnetic energy storage, structure requirements and limitations, configurations of inductors, attributes of high-Tc superconducting materials including thermal instabilities, a relative comparison with the state-of-the-art high energy density power sources, and refrigeration requirements.

This paper briefly describes electric vehicle (EV) magnetic field measurement and evaluation techniques, and compares ac magnetic field results from different electric vehicles (EV). The survey includes nine vehicles from different U.S. manufacturers. These vehicles are powered by either ac or dc motors. Measurement results show that the highest field is generated during regenerative braking and maximum acceleration. Inside the vehicle, the highest field is measured on the driver's seat. Results of measurements also show the importance of shielding the ac magnetic field.

A direction sensor, which measures the terrestrial magnetism and its application to automobiles are discussed. The flux gate type sensor proposed in this paper is sensitive and stable enough for automotive use. A new technique to compensate the car body magnetism is also discussed. The heading display system which consists of a direction sensor, a control circuit and a display device works quite well. A Trip Computer with more attractive features can be easily embodied by applying this sensor.

In automotive applications, magnetic field sensors are widely used for detecting position and current. However, magnetic field sensors are required to be highly precise with good usability. To satisfy demand, we have developed a graphene Hall sensor that senses magnetic fields by the Hall effect. The sensitivity of a Hall sensor is proportional to the carrier mobility, and graphene has an extremely high carrier mobility compared with conventional materials like Si, GaAs and InSb. Thus, graphene Hall sensors are expected to give high sensitivity that will enable sensing of the Earth’s magnetic field. In addition, graphene has a low temperature dependence on carrier mobility due to its ballistic transport, so good usability in actual use is also anticipated. In this paper, we demonstrate a graphene Hall sensor made using conventional Si process technology.

Improved quality and lower costs of industrial metal-forming and bending operations can often be achieved through the application of magnetic forming. In the Magneform process, the workpiece is not touched, but yet, high quality parts are formed without the disadvantages of traditional swaging, welding, pressing and hammering processes. In Magneform* systems, an electric current is used to generate a pulsed magnetic field which applies uniform force to a selected area of the workpiece. The force can create pressures of up to 50,000 psi which move the surface of the workpiece at several hundred feet per second to reshape and join without excessive heat or mechanical contact. Precise control of the magnetic pressure even allows for the formation of high velocity, impact bonds which are stronger than the surrounding parent material. This presentation provides an introduction to magnetic forming and describes several applications used in the automotive industry.

Currently, electrification for vehicles such as battery electric vehicles (BEV), plug in-hybrid electric vehicles (PHEV), fuel cell electric vehicles (FCEV) and hybrid electric vehicles (HEV) are attracting a great deal of attention, due to the urgent need to reduce CO2 emissions created from transportation and energy dependency on crude oil. Honda has set a target achieving two-thirds of total global sales as electrified by 2030. A traction motor is one of the essential components for electrified vehicles. Generally, Interior Permanent Magnet Synchronous Motors (IPMSMs) are used as traction motors due to their high torque and power density, high efficiency and ease of use. The design of rotors, which consist of magnets and electrical steel sheets, is important for IPMSMs since not only average torque, efficiency and quietness depend on it, but also cost. We have developed a novel rotor, which allows for a degree of freedom in the shape of the magnets.

As heavy rare earth elements are become less prevalent, because one-tenth as often in ore deposits as light rare earth elements. Future usage of need to be reduces heavy rare earth, because of resource risks and costs. As such, a method was developed to recover reductions in coercive force and prevent demagnetization temperature from reducing without adding any heavy rare earth elements. First, a heavy rare-earth-free magnet was developed by hot deformation, which limits growth of crystal grain size, and relationships were clarified between coercive force and optimal deforming temperatures, speed, and total rare earth amounts for heavy rare-earth-free magnets. Second, it was made clear that the permeance coefficient can be increased by reshaping the flux barriers, and that the developed hot deformed magnet can be adopted.

Magnetic induction heating can be used to bond automotive seat trim covers to foam pads. A thermoplastic film doped with ferromagnetic particles is placed between the trim cover and foam pad. An induction coil can be designed for specific seat contours in a tool press. When current is applied to the induction coil located in the tool, magnetic flux is induced. Eddy currents generated in the ferromagnetic particles activate the hot melt film. Heat is delivered directly to the bondline. The process does not damage heat sensitive trim materials (i.e.. leather, vinyl) as the tool surface remains cool. Process reversibility permits design for recyclability and a reduction in production scrap rates.

There are two well known basic concepts for achieving magnetic levitation of vehicles: one is based on electromagnetic attraction (EMA); and the second method is based on electrodynamic repulsion (EDR). In turn, each of these concepts have at least two variations (1, 2, 3, 4 and 5)1 This paper presents a description of a lesser known third form of magnetic levitation which in the USSR is called the dc circuit Magnetic Potential Well (MPW) effect, developed by Kozoriz (6); and known in the West as Laithwaite's Magnetic River (13) which, however, is illustrated for an ac circuit. Furthermore, it identifies the boundary conditions which are needed to achieve the dc circuit MPW effect, and illustrates the final forms of the mathematical relationships derived to reduce the MPW concept to practice, in the design of practical high speed Maglev vehicles, for automotive and/or mass transit applications.

There are two well known basic concepts for achieving magnetic levitation of vehicles: one is based on electromagnetic attraction (EMA); and the second method is based on electrodynamic repulsion (EDR). In turn, each of these concepts has at least two variations (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18 and 19)1 This paper presents a third form of levitation known in the Ukraine as the Magnetic Potential Well (MPW) developed by Kozoriz (20, 21, 22 and 23), and in the West as Laithwaite's Magnetic River (24)(25). The MPW concept, in effect, electrifies the passive sidewall levitation coils of the RTRI EDR (16) system to obtain levitation at zero vehicle velocity and during acceleration to cruising speed. This dc electrification of sidewall levitation coils eliminates the need for wheels during acceleration from standstill and deceleration in the station. Specifically, MPW levitation force exhibits a stable positive slope as the levitation gap increases.

This is a comparative assessment of the three magnetic levitation high speed mass transportation systems currently under extensive development, and in the prototype vehicle demonstration stage, in the Federal Republic of Germany (FRG) and in Japan: One approach, which is promoted by Transrapid International (TRI) in FRG, is based on the electro magnetic levitation (EML) concept; a second approach, which is promoted by the High Speed Surface Transport Corporation (HSST), is based on the EML concept developed and licensed from Japan Air Lines (JAL); a third approach, which is promoted by the Railroad technology Research Institute (RTRI) (Sogo Tetsudo Gijutsu Kenkyusho), the developer of the Shinkansen train, is based on the super conductive electro dynamic levitation (EDL) concept.

A commercially available magnetic reluctance sensor is used to determine the angular velocity of turbocharger impeller blades from outside the aluminum housing. Eddy currents are induced in the aluminum blades by blade motion through the magnetic field projected by an externally mounted Samarium-Cobalt permanent magnet. Test results show that a circuit designed to track the blade signal gives an analog voltage output proportional to the frequency of blade passage over the operating range of the Cummins VT-903 and Detroit 8V-71T turbocharged diesel engines. Cam shaft rotational frequency is measured on Cummins and Detroit deisel engines by sensing the motion of ferromagnetic rocker arm parts through a conducting and possibly ferromagnetic valve cover shield. A strong rare earth Samarium-Cobalt magnet and a wire sensing coil are placed outside the valve cover above the rocker arm.

All commonly used speed sensitive power steering assist systems for cars are based on hydraulics. These systems change the pressure or modulate the flow of the conventional hydraulic power steering system. They require some means of actuation in the form of an electromagnetic device such as a solenoid actuator working as a flow or pressure regulator or brushless motor driving a hydraulic pump. Usually they are pulse width modulated controlled by a microprocessor. Therefore, these systems can be quite complicated. This paper describes MAGNASTEER, a novel magnetic speed sensitive system developed at Saginaw Division in cooperation with the NAO Research and Development Center, which is an add on to the basic hydraulic power steering system. The effort variation provided by MAGNASTEER is the result of an electronically controlled electromagnetic torque, which acts as an addition or subtraction to the torsion bar torsional rate, effectively varying the feel of the hydraulic system.

All commonly used speed sensitive power steering assist systems for cars are based on hydraulics. These systems [ILLEGIBLE]ange the pressure or modulate the flow of the conventional [ILLEGIBLE]draulic power steering system. They require some means of [ILLEGIBLE]ctuation in the form of an electromagnetic device such as a solenoid actuator working as a flow pressure regulator or brushless motor driving a hydraulic pump. Usually they are pulse width modulated controlled by a microprocessor. Therefore, these systems can be quite complicated. This paper describes MAGNASTEER a novel magnetic speed sensitive system developed at General Motors Corporation. The effort variation provided by MAGNASTEER is the result of an electronically controlled electromagnetic torque, which acts as an addition or subtraction to the torsion bar torsional rate, effectively varying the feel of the hydraulic system.

For tubular terminals and high power junctions, the magnetic pulse crimping (MPC) could be a technical solution to produce aluminum - copper assembly. LEONI has launched a study to evaluate this technology. Besides, the lifetime of vehicle components is an issue that manufacturers should consider during all the development phases from the conception to the validation in service. Consequently, the quality of the interface aluminum-copper obtained by MPC is evaluated in terms of microstructure, of electrical and mechanical properties and to describe the corrosion behavior.

Magnetic Pulse Welding (MPW), a cold solid state bonding process, is becoming a viable replacement for conventional fusion welding processes and explosive welding for tube to tube applications. The process is presented in this paper together with its fundamental equations. Some examples of similar & dissimilar weld applications are illustrated as well as some interface microstructures.

Cryogenic systems will be a part of the Space Station and future space platforms in a variety of applications, such as propellant management and cooling of scientific instruments. The projected Space Station initial usage of cryogenic propellants is relatively small so the primary refrigeration need is for cooling scientific instruments and various sensors. A potential method for meeting these cooling requirements is the use of a refrigerator based on the temperature changes in certain magnetic materials upon application or removal of a magnetic field; i.e. the magnetocaloric effect. This type of refrigerator, known as a magnetic refrigerator, offers potentially higher reliability and lower power requirements than conventional refrigeration units. Also, the higher power density of the magnetic refrigerator is an attractive feature for space station and space platform applications.

Many synchronous electric motors require a very accurate position sensor compatible with a sinusoidal control. The purpose of such a control is to enable an efficient and smooth operation enhancing the comfort by limiting vibrations. In some cases related to mechanical constraints, we have to deal with through-shaft design. One can quote for examples power drives for Electric or Hybrid Electric Vehicles as well as for Electric Power Steering motor. More generally, these sensors need to keep a simple and robust design and a restricted number of parts as they are submitted to high vibration levels, a wide temperature range and speeds of several krpm. In order to meet such requirements, MMT has developed a magnetic sensor principle offering a competitive alternative to the conventional inductive resolver type sensors. The basics of this solution is a through shaft angular position sensor using one or two Hall-effect probes.

Magnetic resonance imaging (MRI) has been used to investigate gas flow in diesel and gasoline particulate filters, exploring gas flow both within the channels and also at the entrance and exit of the filters (expansion and contraction effects). The latter measurement can be used to measure turbulent diffusivity in the filter bulk flow characteristics, and therefore estimate the importance of entrance and exit effects in contributing to overall filter back pressure as the filter properties and/or exhaust flow changes (i.e. with Reynolds number). The former measurement gives information that can be used to evaluate filter performance, in particular with respect to filtration efficiency, and examples will be shown from our measurements on diesel filter systems.

There is an ever-present risk for the lower ram on a riveting machine to suffer a damaging collision with aircraft parts during automated fastening processes. The risk intensifies when part frame geometry is complex and fastener locations are close to part features. The lower anvil must be led through an obstructive environment, and there is need for crash protection during side-to-side and lowering motion. An additional requirement is stripping bolt collars using the downward motion of the lower ram, which can require as much as 2500 pounds of pulling force. The retention force on the lower anvil would therefore need to be in excess of 2500 pounds. To accomplish this a CNC controlled electromagnetic interface was developed, capable of pulling with 0-3400 pounds. This electromagnetic safety base releases when impact occurs from the sides or during downward motion (5 sided crash protection), and it retains all riveting and bolting functionality.