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This paper proposes a current limits distribution control strategy for a parallel hybrid electric vehicle (parallel HEV) which includes an advanced powertrain concept with two electrical driving axles. One of the difficulties of an HEV powertrain with two electrical driving axles is the ability to distribute the electrical current of one high voltage battery appropriately to the two independent electrical motors. Depending on the vehicle driving condition (i.e., car maneuver) or the maximization of the entire efficiency chain of the system, a suitable control strategy is necessary. We propose an input-output feedback linearization strategy to cope with the nonlinear system subject to input constraints. This approach needs an external, state dependent saturation element, which translates the state dependent control input saturation to the new feedback linearizing input and therefore preserves the properties of the differential geometric framework.

This activity is focused on more electric and all electric type power systems for air vehicles. The scope of which includes source, distribution and user contributions to electrical power quality, failure modes, coordination, system reliabilty and robustness, impacts of being flight critical and the gaps which exist in present standards and guidance documents.

This SAE Aerospace Information Report is intended to provide advanced methods for wire selecting and sizing in aerospace application as a continuation of AIR6540, Fundamentals in Wire Selection and Sizing for Aerospace Applications. Also, it will provide valuable information for the electrical design engineer to verify the proper wire selection and validate a set of system design requirements which includes meeting environmental and installation constraints.

EPS stability is an essential property that defines EPS ability to provide secure operation under required range of operation scenario. Power system stability is defined as “the ability of an electric power system, for a given initial operating condition, to regain a state of operating equilibrium after being subjected to a physical disturbance, with most system variables bounded so that practically the entire system remains intact”. This is applicable for AC and DC systems and has to address steady state conditions, transient conditions as well as high power loads connection / disconnection on the network.

The need for developing this standard is driven by the quickly evolving field of electrified propulsion for aircraft. Industry is moving forward in development of a broad range of high voltage primary power systems. There is an immediate need to standardize power quality requirements for design, analysis, verification, and testing for these types of systems.

Technical requirements especially related to the design and construction and the minimum performance requirements (including qualification test conditions) for PM motors and power converters (operated as VFDs) used as the prime mover for more-electric, hybrid-electric, and fully-electric aircraft propulsion systems.

This AIR intends to better document and tabulate electrical load dynamics that influence power source capacity, power quality and stabiltiy.

To determine the end-of-life criteria of electrical insulation materials and components and predict insulation life in high voltage aviation applications

To provide test guidelines, recommendations and referenced standards for insulation materials in a high energy system especially at high voltages (AC, DC and PWM) and at high altitudes, in the purpose of defining/measuring the effects of insulation ageing.

Currently, conventional spark-ignition engines are unfit to satisfy the growing customer requirements on efficiency while complying with the legislations on pollutant emissions. New ignition systems are being developed to extend the engine stable operating range towards increasing lean conditions. Among these, the Radio-Frequency corona igniters represent an interesting solution for the capability to promote the combustion in a much wider region than the one involved by the traditional spark channel. Moreover, the flame kernel development is enhanced by means of the production of non-thermal plasma, where low-temperature active radicals are ignition promoters. However, at low pressure and at high voltage the low temperature plasma benefits can be lost due to occurrences of spark-like events. Recently, RF barrier discharge igniters (BDI) have been investigated for the ability to prevent the arc formation thanks to a strong-breakdown resistance.

Electric vehicles have a limitation of limited range and long charging time. Energy optimization plays a very crucial role in determining the range of an electric vehicle. The innovative system proposed here gives the opportunity to reduce energy wastage and efficiently direct the electrical energy to improve the driving range of a 9 meter AC electric bus. The high voltage air conditioner unit alone consumes more than 40% of the electrical energy stored in the traction battery which reduces the driving range of the electric bus drastically. The proposed system optimizes the air conditioner utilization to direct cool air only in areas where passengers are present. Buses do not always run on full capacity, when there are less number of people in the bus the system detects the locations of the passengers using sensors and occupant detection algorithm, this enables the controller to identify the areas where cooling has to be focused and where cooling can be reduced or stopped.

Advanced combustion engines dominate all automotive applications. Future high efficiency clean combustion engines can contribute significantly to sustainable transportation. Effective ignition strategies are studied to enable lean and diluted combustion under considerably high-density mixture and strong turbulences, for improving the efficiency and emissions of future combustion engines. Continuous discharge and multi-site ignition strategies have been proved to be effective to stabilize the combustion process under lean and EGR diluted conditions. Continuous discharge strategy uses a traditional sparkplug with a single spark gap and multiple ignition coil packs. The ignition coil packs operate under a specific time offset to realize a continuous discharge process with a prolonged discharge duration. Multi-site ignition strategy also uses multiple ignition coil packs.

As the global warming due to carbon footprint is very alarming, vehicle emissions are getting stringent day by day. In such situation vehicle hybridization or fully electric vehicles are of obvious choices. However in any of the cases the battery cooling is a big concern area. As the heat produced by the battery need to be dissipated in the long run, it is of utmost need to develop and understand the battery cooling system. Present paper describes the experimental investigation of a battery cooling circuit. A complete bench comprising of both primary and secondary circuit is used for the testing. The primary circuit has a cooling unit with TXV, condenser and electric compressor run by high voltage. The secondary circuit consists of a chiller (integrated with TXV) unit responsible for battery cooling. The whole circuit typically resembles with one of dual air conditioning unit and uses one of known refrigerant used in vehicle AC system.

A new method of evaluating the anti-cratering properties of precoated steels has been developed which detects minute differences among materials. The anti-cratering properties of precoated steel sheets are evaluated by measuring the variation of current with electrodeposition time (current-time profile) at the initial stage of cathodic electrocoat deposition. Although some current peaks were observed in the current-time profiles, the slight differences of anti-cratering properties in precoated steel sheets were able to be evaluated by measuring the last current peak height. In the case of cratering at high applied voltage, the peak height of the last current peak was high and the variation of the current was vigorous. On the other hand, when few craters were generated, the last current peak height was low.

New expressions are given in the present paper for the output signals and input power requirements for the three principal torque sensor designs -- the branch, cross, and solenoidal designs. Procedures are described for evaluating model parameters. The parameters are then used in computer-model simulations of the three sensor designs. Calculations are made for each sensor configured to fit into the same space on the same shaft. The shaft was made of either maraging steel or SAE 1010 steel -- both of which have useful magnetostrictive properties. It is shown that for a fixed shaft length, for both shaft materials, largest signal level is obtained from the solenoidal sensor, followed by the branch sensor, and the cross sensor gives the smallest signal. On the other hand, the solenoidal sensor consumes the greatest amount of input power and requires the highest excitation voltage. Physical origins of this behavior are discussed in the paper.

During the past two years, a group of interested engineers have assembled and formed the SAE Dual/High Voltage study group. The participants have an awareness that today's 12 volt electrical power system may not be able to keep pace with forthcoming electronic technology and continued increasing electrical loading in modern automobiles. Their purpose is to address the implications of higher and/or multiple voltages and to make recommendations that will facilitate some acceptable global standards. This paper traces the course of the study committee work, reports on their deliberations and interim conclusions, and outlines items currently under study and discussion. Of special interest are the recommendations on the limit for an admissible contact voltage and the schematic diagrams of electrical systems discussed by committee members as possible candidates for the vehicle of the future.

The electrical power system is the vital lifeline to most of the control systems on modern automobiles. The demands on the system are highly complex, and a detailed understanding of the system behaviour is necessary both to the process of systems integration and to the economic design of a specific control system or actuator. The following general trends are observed:- Increased use of electrically actuated systems Increased use of electronic control Increasing requirements for high integrity power supplies for safety critical systems Increased average electrical power consumption (heating, actuation, control systems) Increased electrical demand at engine idle combined with reducing idling speeds Increased interest in higher voltage systems. Electrical system problems are a major cause of road-side breakdowns.

The need for salable features, lower exhaust emissions, greater efficiency and improved safety for tomorrow's vehicles is increasing the demand for electrical power. Raising vehicle system voltage from twelve volts is seen as an effective step toward meeting future power requirements while increasing generation, rectification, transmission and switching efficiencies. Higher system voltage will require higher voltage energy storage devices, i.e. batteries. Implications for the design and function of vehicle batteries, as well as manufacturing and reliability, are substantial.

Doubling or quadrupling the present 12V electrical system provides advantages and disadvantages to many components, and to systems that utilize these components. The effect that this increase has on vehicle electronics starts at the semiconductor component level. Several design implications including technology tradeoffs must be evaluated, and the cost impact on silicon area, processing complexity, and current process limitations considered. This paper focuses on the impact of increasing the system voltage to 24V or 48V with and without centralized load dump transient suppression. The semiconductor devices principally affected are transient suppression devices, power semiconductors, smart power ICs and linear drivers. In addition, the effect of a change in system voltage on MCUs, DSPs, memory devices, and other interface circuits will be discussed.

The simplicity, reliability, and weight reduction potential promised by high voltage direct current (HVDC) electrical power systems has enticed aircraft developers to propose the use of such systems in modified form for advanced aircraft. However, HVDC systems have not been flown on any military or commercial aircraft and little has been done to independently validate the tradeoffs made and to analyze the impact a HVDC system will have on Naval aviation and its support. To rectify this, the Naval Air Systems Command established a working group consisting of Defense Department activities concerned with aircraft electrical power research and development, testing, avionics development, logistics, and safety. The working group was free to examine all aspects of the development, implementation, and use of HVDC aircraft power systems.