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Electrical driven compressors (EDC) are mounted on the automotive driveline to compress refrigerants in an automotive air conditioning system. The electrical power delivered by the battery is converted to mechanical power by an inverter and an electrical motor. The inverter is composed of a printed circuit board (PCB) with assembled electronic components. For the inverter part of the EDC, the vibration failures are predominant followed by thermal failures on electronic components. Hence robust methodology is necessary to improve the strength of the design under vibration environment through Finite Element Analysis. In this paper, a multi-fidelity methodology to validate automotive electronic components under harmonic loading through Finite Element Analysis is presented. This multi-fidelity methodology allows the risk of failure to be assessed at the earliest stages of product design, when changes are easy to make and have a low financial impact.

An innovative method for the use of electrical machines and drives as sensors in automotive applications is presented. The innovations and advantages resulting out of the described procedures are superior diagnostic capabilities. As a main result higher efficiency and reliability of electrical machinery and mechanical systems in cars may be obtained. An accurate failure recognition of electrical and electromechanical components and systems in a pre-failure-phase is possible, so there is an opportunity for preventive exchange of parts and systems. The presented diagnostics methods, contains not only the opportunity for time- and cost-optimised car service, but also for additional functionalities in electromechanical systems working with drives.

The paper deals with on board power plants for electric road vehicles, supplied by fuel cells. As it has already been shown [1], the plants’ performances may be analysed by means of a simple equivalent electric network. The paper contributes to this performance analysis by giving some characteristic surfaces of supplied dc voltages and to the definition of control strategies by suggesting a sample structure of a digital programme for the management of the dc plant electrical energy sources.

This study focuses on the durability characteristics of the electrically heated converter (EHC). The basis of these investigations was the development of tests specific to the electrical heating function. This paper summarizes tests used to develop dielectric barriers and to confirm the durability of the final material used on W.R. Grace & Co.-CONN., Cam-E-Lite™ EHC designs. The properties evaluated include critical cohesion and adhesion characteristics between the coatings and metal supports as well as the thermal stability of the coatings in high temperature environments. Results are presented to address the durability of dielectric barriers applied to individual heater leaves or incorporated into functional EHCs.

With the significant amount of automation and electrification paving the way for the future of automobiles, the complexity and design of the electrical harnesses have evolved to a point where a minuscule discontinuity can cease the operation of a mechanically pristine vehicle. A vehicle equipped with the best-in-class systems does not always guarantee everlasting operations every time. The wiring harness of any vehicle by its design aspect is one of the most crucial and vulnerable components. Prone to succumbing to factors such as electrical overloading, physical impact, unprofessional handling, and even sabotage, presently there lies no backup system to compensate for the loss of functions of the main electrical network in the event of a failure. In the interest of rapid re-instating of primary functions in a vehicle to make it operational in the event of an electrical failure, the concept of an emergency piggyback electrical network is delineated.

Dispersed electrical energy storage systems are expected to work for load leveling, fluctuation smoothing, uninterruptable power supply and emergency power source. Their introduction seems to be essential in order to control the future complicated energy utility networks since they can handle both active and reactive power. In this paper, the problem of the future electric distribution utility has been pointed out, and the characteristics of promising energy storage systems, such as pumped hydro, CAES, secondary batteries, SMES, flywheel and capacitors have been investigated and compared with each other. From the result of the investigation, their suitable application fields have been clarified.

Given the goal of developing energy-optimized aircraft that employ increasingly higher power loads such as electric flight control actuation, directed energy weapon systems and on-demand cooling systems, advances in battery technology and associated integration methodology will be required to achieve a robust electrical power system design. Batteries based on various Lithium-Ion chemistry technologies represent a 50% improvement in both specific energy and specific power over legacy NiCad and Lead-Acid chemistries. However, along with these benefits come challenges in terms of overall safety, cost and availability. Safety considerations primarily include failure modes that result from the battery being subjected to short-circuit conditions and over-charge conditions. Cost and availability challenges arise primarily from one-off point designs and ensuing low production volumes, but also stem from limited marketplace competition.

The value of “ultracapacitors” (also referred to as “supercapacitors” or “electric double layer capacitors” in some literature) as an augmentation device when placed in parallel with “electrochemical” energy storage (i.e. battery) is presented in this paper. Since ultracapacitors possess unique attributes due to their higher value of energy storage density (or Joules/WattHrs per mass) compared to conventional capacitors while maintaining the peak power providing capability (to some degree) typical of conventional capacitors they may provide a near term solution in applications demanding longer battery operating life when placed in parallel. Such demands may be pronounced by the onset of More-Electric-Aircraft peak loads and “cold-crank” Auxiliary Power Unit (APU) electric-starting in demanding cold temperature environments.

Now as never before electrical engineering is an exciting, fast-paced, and dynamic profession requiring life-long study for continued practice. University programs must provide the educational basis for each electrical engineering graduate's continuning professional development. Yet these programs are themselves experiencing forces and accelerations of crisis proportions during this present period of rapid change. This paper examines some aspects of our educational system that are rooted in the past, have served the profession well, but now are contributing undesirable force components. It also outlines the circumstances associated with the present expanding sphere of professional education, educational delivery systems, and explores the multi-facted impact of emerging microelectronics technology on electrical engineering education. Targeted are areas in need of streamlining, responsibilities of the profession in this time of challenge and ideas concerning industry support.

The economic benefit of reliability in engine electrical equipment is a product of application, design and technology, but it is also dependent upon knowing limitations of the individual components of the systems, the interrelationships of the systems, and the ability to identify and specify new requirements that result from new use concepts permitted by increased perfection in engines and vehicles. Reliability in electrical accessories can be best interpreted as the ability of the operator to start and run his engine without undue concern. As technology increases vehicle and engine perfection, technology also permits improvements in the application and design of electrical equipment for engines.

Electrical low pressure impactor ELPI was modified to measure particles below 30 nanometers in aerodynamic diameter. This was accomplished by adding a filter stage to collect and measure nanoparticles. The charging unit of the instrument was modified to increase the charging efficiency of the smallest, nanometer sized, particles. The modified charging unit was calibrated and the new construction of the ELPI was tested in laboratory and in vehicle dynamometer test cell. Measurements performed in the engine test cell showed that modifications improve the size range and measurement capability of the ELPI for engine emissions.

Initial results are reported for the effects of electrical body forces on heat transfer performance of an instrumented spray cooling experiment. Heat transfer performance is documented for ranges of electrode voltage, spray volume flow rate, and heater power level using a Thick Film Resistor heater. The heat transfer coefficient increases with increased spray flow rate, and also increases somewhat versus heat flux. Without the electrical body forces, different brass and PVC spray nozzles show significant variation in spray cooling performance (order of ±5-15%) whenever the nozzle is realigned. Changing the nozzle-to-heater spacing results in similar performance variations. Initial Kelvin force electrode designs show no improvement in heat transfer performance using FC-72, while a Coulomb force electrode geometry and a second-generation Kelvin force electrode design both show modest but consistent improvements (order of 10% in heat flux; order of 5% for Nusselt number) using HFE-7000.

The conventional method of making rotational moulding part is by heating the cast aluminium mould or sheet metal mould by hot air medium which has its own limitation on energy loss, the other means is by direct heating and cooling of mould by passing hot oil/water in the mould to have better energy efficiency but leakage and safety problems associated with pumping pressurized hot oil/water. There is no solution available for prototyping rotational moulding parts using design intended material. The current practice of prototyping with the conventional method is expensive and time-consuming. In this work, a simple method is presented to produce a rotational moulded part with a breakthrough in-mould construction, which is Composite Mould Technology (CMT) with glass fibre reinforced epoxy resin built-in with electrical heaters. The project focuses were on proving CMT in comparison with the current production method. CMT reduce the cost by 90% and time to build Protomould by 85%.

Ignition systems are categorized into two general groups: one producing energy in short high power bursts and the other in long low power bursts. Capacitor discharge systems for jet engines and exploding bridge wire type of initiators are of the first group. Constant current transformers and induction vibrators, producing high tension, glow plugs and hot wire initiators utilizing primary power directly are in the second group. Methods of control, advantages and limitations, and susceptibility to external stimuli are compared with emphasis on electro-magnetic compatibility. Capacitor discharge systems for exploding bridge wire initiators are particularly emphasized because of their increasing use on missiles.

The objective of this paper is to propose that the automotive engineering “legacy” approach of assuming that vehicle electrical return paths using conductive structural components have zero (0) ohms of impedance, needs to be reviewed. The process in this review consists of the development of an equivalent circuit composed of both real (“resistive”) and reactive elements (due to inductance and capacitance). This issue needs to be addressed due to the increased complexity of electrical and electronics systems in vehicles and the use of the vehicle structural (such as chassis, frame, or bracket) components to provide a path for the return of electrical power and/or signals as a way to eliminate additional wiring manufacturing issues, cost, and weight contribution to a vehicle.

Electrical Impedance Spectroscopy (EIS) consists on the measurement of electrical impedance at different frequencies. The electrical impedance of a biological sample has a specific behaviour with respect to the frequency of the electrical current injected. This behaviour can be distinguished from that of a sample without cells or with dead cells. NTE started the development of this technology in the frame of a project of the European Space Agency (1) and in collaboration with the UPC. This technology has started a technology transfer process, in which three companies from three different fields: a brewery (Freixenet, S.A.), a water treatment plant engineering company (Indeco, S.A.) and a pharmaceutical company (Biokit, S.A.) have evaluated the technology for their production requirements. Specifications were issued for each process considered in case: On-line viable yeast cell determination in CAVA production line.

In recent years, bearing electrical failures have been a significant concern in electric cars, restricting electric engine life. This work aims to introduce a coating approach for preventing electrical erosion on 52100 alloy steel samples, the most common material used on manufacturing bearings. This paper discusses the causes of shaft voltage and bearing currents, and summarizes standard electrical bearing failure mechanisms, such as morphological damages and lubrication failures. Alumina coatings are suitable for insulating the 52100 alloy steel samples because alumina coatings provide excellent insulation, hardness, and corrosion resistance, among other characteristics. The common method to coat an insulated alumina coating on the bearing is thermal spraying, but overspray can cause environmental issues, and the coating procedures are costly and time-consuming.

This paper presents a short discussion of lesser known air-craft electrical interference problem areas and their causes. Each problem area is illustrated with a typical example that has caused trouble on Boeing transports. Also, the size and complexity of electrical interference possibilities on modern transport type aircraft are briefly discussed.

This paper describes modeling and simulation technologies used to simulate the electrical systems of Army vehicles using Matlab/Simulink coupled with graphical user interface software. The models were built using Mathworks' Matlab/Simulink software in conjunction with the SimPowerSystems Toolbox, a toolkit provided by Mathworks that provides models of basic electrical components such as capacitors and inductors, in addition to more advanced components such as diodes and IGBT's. The current results of this ongoing effort are presented and discussed.

In order to further improve the influence of the electrically interconnected suspension (EIS) on the ride-comfort, a four-port electrical network (EN) is established in the SIMULINK environment based on the existing EIS research and applied to the passive model of the cabin system. This model is a passive suspension model composed of the road surface excitation, the main suspension, and the cabin suspension. The electrical network of EIS is connected with the cabin suspension section so that the interconnection is completely achieved in the cabin suspension system. The simulation results indicated that the four-port EIS is able to decouple the cabin motion in the three directions of heave, pitch, and roll, and improved the ride comfort and handling stability by adjusting the parameters of the circuit components.