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This paper adds thermal properties to previously developed [1] [2] [3] electrical Saber templates and incorporates these templates into a functional Electrical Power Subsystem (EPS) simulation. These combined electrical and thermal templates enable the complete and realistic simulation of a vehicle EPS on-orbit. Applications Include on-orbit energy balance determinations for system load changes, initial array and battery EPS sizing for new EPS development, and array and battery technology trade studies. This effort proves the versatility of the Saber simulation program in handling varied and complex simulations accurately and in a reasonable amount of computer time.

With today's trend toward reduced spending for new weapons systems comes the desire to extend the useful life of existing airframes, and to upgrade aircraft and mission avionics suites to meet the existing and future threat. While upgrades may include structural and avionics improvements, the electric power system usually remains unchanged; often becoming the major cause of aborted missions and aircraft down-time. A specific need exists to identify a systematic approach for developing improvements to existing electric power systems. This paper explores this problem and develops a methodology which could be applied to its solution.

Mechanical and electrical properties of 22 glass-and asbestos-fortified thermoplastic resin systems are presented. Large increases in tensile and flexural strength are noted with the glass- and asbestos-fortified nylon compounds; increases for other fortified resins are also qualitatively detailed. Flexural modulus data also demonstrate the ability of fortifiers to increase rigidity dramatically. Unnotched izod impact strengths are generally reduced by addition of fiber fortifiers, while notched izod impact strengths are increased for some resin systems and decreased for others. Increases in heat deflection are generally realized. The d-c electric properties of dielectric strength and arc resistance are generally enhanced in glass fiber-fortified thermoplastic resins. The a-c electric properties of dielectric constant and dissipation factor are similarly increased. Both increases and decreases in volume resistivity data are noted with the addition of fiber fortifiers.

In view of the low energy density of the electrochemical storage units available at the present time, only the development of such electric vehicles that are intended for transportation jobs within the cities appears to be worthwhile. The speeds mainly used with this type of application can be controlled by field weakening of the electric motor. The function of the power electronics which serves only to control the starting range can be taken over by a hydrodynamic transmission. In this case, the design of the drive must take into consideration the basic differences between the torque versus speed characteristics of a hydrodynamic converter and an electric motor. With a suitable design, this power train has, on the one hand, a good efficiency of transmission and can meet, on the other hand, further demands conditioned by the energy storage.

Electrical Power and Signal Distributions System in a vehicle is the most important among the Automotive Electrical and Electronic systems. In fact any electrical or electronic systems are realized and are physically formed by the Electrical Wiring Harness. This is a system in itself with the set of wires and connectors connecting various devices to feed the power and act as physical channels for signal transmission and serial data communication. Thus, the Electrical Wiring Harness becomes huge complicated systems in a vehicle. Because of the number of wires, cables and the specific connectivity requirement the design and development will become very difficult. Further, the complexity is manifold due to number of harnesses in a vehicle and different operating conditions in different zones of the vehicle. The design and development of an Electrical Wiring Harness involves primarily the design of the electrical circuit. This is based on the vehicle architecture.

An electrical quick heat system, composed of a three-phase alternator, a resistive heating assembly, and simple controls can be easily integrated with a standard hot water heating system or utilized with its own blower and plenum chamber. Such a system, with a 5 in. diameter alternator, can supply up to 2.5 kW of power which can be used to give greater than 100 F air temperature boost in less than 30 sec. The simplicity of the system should bring it within most economic bogeys for automotive quick heat systems.

The use of a Calrod type electrical faceheater, powered by two 12V heavy duty batteries in series, as a regeneration initiator for a 12 in (30.5 cm) diameter × 12 in (30.5 cm) long segmented honeycomb ceramic filter is described. Recent test data, obtained on Deutz mining engines during the regeneration process, is presented. The effects of various regeneration parameters on the reliability and long-term durability of the filter is discussed together with the effect of fuel additives. The test data include both the measured temperature profiles and calculated thermal stresses in the filter with and without fuel additives.

A new electrical remote control system has been developed to solve an existing control compatibility problem in agricultural machinery caused by the trend toward larger tractors and implements and adoption of the tractor cab. This control system consists of a tractor mounted control box and one or more implement mounted actuators that provide remote monitoring and control of implement functions from the tractor operstor's station. The control box and actuators are coupled by a multiterminal connector that has potential for standardization. This portable control system has value to the user in that it affords a new measure of comfort in more compatible tractor-implement operation.

Major goal for the development of hybrid vehicles is to increase fuel efficiency. Legislation and tax incentives are supporting this motivation. But also the performance can be improved. By realizing a boost function e. g. it is possible to compensate the poor start up behaviour of turbo charged engines. In case of the hybrid system that will be described in the following article additional targets were defined for the development: Add on - structure Flexible dimensioning of the starter-generator Minimal application efforts. The definition of the hybrid concept requires first a focus on the base transmission. Driven by above mentioned targets the investigation of existing gearboxes leads to a dual clutch transmission. Regarding the requirements for controllability independent from the combustion engine for start/stop and again good efficiency the electro-mechanical actuation concept is chosen.

Some experimental results on discharge development in ultra-long air gaps (breakdown voltages, parameters of the leader stage) are presented. The obtained data are compared to available data on breakdown of long air gaps under positive switching pulses with critical time-to-crest. Existing empirical and theoretical formulae for calculation of sparkover voltage of rod-to-plane air gaps are reviewed. Electrical strength of ultra-long air gaps is considered based on general analysis of physical processes in leader stage of spark discharge. The electrical strength has been thus expressed in the given paper via some characteristic stabilization electric field for each spatial scale. As predicted here, the electrical strength along the lightning development path may decrease down to 3÷10 kV/m.

This paper addresses the fundamental issues faced in the aircraft electrical system architectures. Furthermore, a brief description of the conventional and advanced aircraft power system architectures, their disadvantages, opportunities for improvement, future electric loads, role of power electronics, and present trends in aircraft power system research will be given. Finally, this paper concludes with a brief outline of the projected advancements in the future.

A status report on the development of an electrical test-facility for the SEAS DTC (Systems Engineering for Autonomous Systems, Defence Technology Centre) project ‘ultra-compact intelligent electrical networks’ is presented. The electrical platform has initially been based on a small, aerial, uninhabited autonomous vehicle architecture, which consists of two electrical generators, a DC distribution system, an energy storage device and various electrical loads. The issues that arise when implementing such a test platform are discussed and a suitable design strategy is proposed along with progress to-date.

Work lights with high power rating consume high current. Since the battery voltage is fixed, high currents are needed to generate the necessary power (wattage). This makes it difficult to manage the load on the Electronic Control Unit (ECU) responsible for controlling the work lights and also on the entire electrical system of the vehicle. It is possible to prevent the system from getting over loaded by employing effective means of work light control techniques. These techniques differ based on the type of work lights connected on the vehicle. There are three types of work lights available in the market. Halogen work lights, High Intensity Discharge (HID) work lights and Light Emitting Diode (LED) work lights. HIDs are not preferred by most customers due to their high warm up times & cost/unit. The other two types of lights, i.e. LED & Halogen, are comparatively less expensive. They also need negligible warm up times which are not objectionable to the vehicle operators.

Recently electric and electronic devices in vehicle have been rapidly increasing. Because the dynamic characteristics of these systems are too much complicated, it is getting very difficult to predict the change of electrical energy accurately. Especially, since the lead-acid battery has a fast aging process, managing the electrical energy in vehicle becomes more difficult. This paper shows the electrical energy simulator, which consists of a battery, an alternator and various electrical devices. In particular, proposed aging battery model was implemented using a finite element method (FEM) based on electrochemical approach. And the thermal characteristic of alternator is also focused on getting reliable performance. Finally, we validated the electrical energy simulator including this battery model on the actual conditions in vehicle.

The Space Exploration Initiative (SEI) will need a wide variety of manned systems with requirements significantly different than those for existing systems. This paper discusses the need for a space power utility concept, and examines the impact of this concept on the engineering of space power systems. Almost all existing space power systems distribute low voltage direct current. Although they have been very successful, increasing power system requirements in recent years have exposed their inherent limitations and led to the proposal of a number of alternatives including high voltage dc, and ac at various frequencies. This paper, drawing on the experience gained from Space Station Freedom and SEI systems studies, discusses the factors that may affect the choice of frequency standards on which to build such a space power utility.

Minimum battery pack requirements for emergency vehicle cranking/charging system survivability can be determined through simple calculations obtained from on-vehicle measurements. A standard operating procedure is also presented to reduce on scene vehicular charging system failures.

Sealed nickel-cadmium and sealed lead batteries offer a practical means for holding up volatile electronic memories and for relieving the automotive SLI battery of intermittent electronic loads during ignition-off periods. While serving the more conventional functions, the low dynamic impedance of these sealed batteries can act in conjunction with a simple charging circuit, to significantly isolate the electronic circuits they serve from damaging and disrupting electrical system transients such as load dump.

This paper presents a new concept for an electro-mechanical cam phase shifting device (eCPS) along with its control structure. The proposed eCPS features a positive differential gear mechanism with a unique self-locking characteristic. Proof-of-concept simulations were performed using both ADAMS and Simulink analysis tools to evaluate the validity of the concept and its performance. Comparisons with other cam phasers were also discussed. Results confirmed the frictional locking mechanism which not only allows for reduced control effort but also provides the system with an important fail-operational feature. The frictional locking mechanism significantly reduces the reliability burden upon the electric machine. It was indicated that eCPS compares favorably with hydraulic cam phasers in shifting range, position holding, slew rate, system stiffness and power consumption. The performance of eCPS is independent from engine performance characteristics and environmental conditions.

The conventional transistor coil ignition system with coil-out energy up to 100 mJ might not be sufficient to establish a self-sustained flame kernel under lean combustion with strong in-cylinder flow motion. Further increase of the discharge current will decrease the voltage across the spark gap, which will affect the calculation of the energy delivered to the spark gap. In this paper, the relationship between the discharge current and gap voltage is investigated, and it is discovered that the spark energy doesn,t increase monotonously with the increase of the discharge current. However, engine test results still indicate a positive impact of discharge current amplitude on the engine performance.

This paper reviews the development of an electrical diagnostic presentation adopted for John Deere products worldwide. Deere has adopted IEC 617 electrical symbols and incorporated them into a standard presentation format to simplify and improve the communication of electrical information to dealer technicians who service John Deere equipment. The diagnostic presentation is designed to provide the end user, the service technician, a common method for diagnosing electrical problems. It utilizes a combination of diagrams prepared by product engineering and service groups. Engineering is responsible 1) for developing a functional schematic diagram to explain the operation, function and interaction of the electrical devices, and 2) for developing a wiring diagram to show the harness flattened out with connectors and devices.