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A few years ago, the automobile industry agreed to adopt standards for a new voltage for the production and use of electrical power. The perception was near universal that 14 Volts was at the limits of its capability, and that 42 Volts would be adopted in a rush. The universal perception was wrong. Since then, much of the auto industry has encountered hard financial times. In a totally separate development, parts suppliers introduced innovations at 14 Volts, some of which a few years ago were thought to require 42 Volts. Today, there are 42-Volt cars and trucks for sale, but only at numbers far lower than necessary to begin to achieve economies of scale. But the factor which caused the industry to develop the 42 Volt standard, the growth of electricity use on motor vehicles, continues with no sign of letup. Further, the true technical obstacles to adoption of 42 Volts have been discovered and at least provisionally solved.

The electrification of accessories using a fuel cell as an auxiliary power unit reduces the load on the engine and provides opportunities to increase propulsion performance or reduce engine displacement. The SunLine™ Class 8 tractor electric accessory integration project is a United States Army National Automotive Center (NAC™) initiative in partnership with Cummins Inc., Dynetek™ Industries Ltd., General Dynamics C4 Systems, Acumentrics™ Corporation, Michelin North America, Engineered Machine Products (EMP™), Peterbilt™ Motors Company, Modine™ Manufacturing and Masterflux™. Southwest Research Institute is the technical integration contractor to SunLine™ Services Group. In this paper the SunLine™ tractor electric Air Conditioning (AC) system is described and the installation of components on the tractor is illustrated. The AC system has been designed to retrofit into an existing automotive system and every effort was made to maintain OEM components whenever modifications were made.

With the increase of hotel and ancillary loads and replacement of engine driven mechanical and hydraulic loads with electrical loads, automotive systems are becoming more electric. This is the concept of More Electric Cars (MEC) that necessitates a higher system voltage, such as the proposed 42V, for conventional cars. In this paper, the development of the 42V electric power system for vehicle applications is reviewed. The system architecture and motor drive problems associated with the 42V electric power system are analyzed. Solutions to these problems are also discussed.

The automotive industry is transitioning from the present 14V electrical system to a 42V system. This voltage evolution is due to the number of new systems (safety, fuel economy and customer convenience) being developed which require increased electrical power that a 14V system cannot deliver. During this transition, it will be necessary to control 14V subsystems in a 42V architecture. This paper presents 42V PWM (Pulse Width Modulation) voltage conversion and control technologies as a solution to control these 14V subsystems.

The growth in electrical power demand in future vehicles is expected to significantly exceed the four to five percent annual increases experienced over the last two decades. Continued electrification of traditionally mechanical loads, such as power assist steering, as well as the introduction of new loads, such as AC power points, will overburden the conventional 14V power generation and distribution system. The cost of the electronics to control these new high power systems will add to the challenges associated with the transition. A higher electrical system voltage will be required to meet these ever increasing loads and will help to reduce the control electronics costs. This paper will provide projections of potential future electrical system loads and compare some approaches that could be employed to provide the electrical power to meet the needs.

Fuel economy and emission reduction assume significant importance for automotive research activities and conversion of many mechanical / hydraulic loads to electrical loads helps in realizing this objective. As a result, many electrical power hungry loads are anticipated to be introduced soon in global market with average power requirement exceeding the practical limit of the present automotive electrical system implying the necessity of a suitable higher voltage system. Many OE and component manufacturers have come to a consensus to choose 42V as the system voltage for future passenger cars considering various aspects. This paper highlights the advantages of the high voltage system together with some of the issues associated with the new system.

As the vehicle electrical system migrates to the recommended 42-volt system in the future, 42V incandescent lamps will not be practical due to their short filament life. Alternatives to incandescent lamps are discussed. However, due to the inherent simplicity and cost advantage over alternatives, incandescent lamps remain the light source of choice for the auto manufacturer. A scheme to power the current 12V incandescent lamp directly from the 42V line will be presented as a viable low cost solution for the 42V system. This scheme utilized pulse width modulation (PWM) which eliminates the use of expensive DC to DC converters. Implementation schemes, preliminary results, advantages and issues are presented.

Mild hybridisation, using a 48 V system architecture, offers fuel consumption benefits approaching those achieved using high-voltage systems at a much lower cost. To maximise the benefits from a 48 V mild-hybrid system, it is desirable to recuperate during deceleration events at as high a power level as possible, whilst at the same time having a relatively compact and low cost system. This paper examines the particular requirements of the battery pack for such a mild-hybrid application and discusses the trade-offs between battery power capabilities and possible fuel consumption benefits. The technical challenges and solutions to design a 48 V mild-hybrid battery pack are presented with special attention to cell selection and the thermal management of the whole pack. The resulting battery has been designed to achieve a continuous-power capability of more than 10 kW and a peak-power rating of up to 20 kW.

The transformation of the automotive industry will be shaped mainly by the markets North America, Europe and China, which account for more than two thirds of the yearly global car production. All three markets have challenging fuel consumption, CO2 and emission regulations in place and under discussion, which are forcing the automotive industry to make their power train technology more efficient. But not only governmental regulations are driving the change, increasing urbanization intensifies local environmental pollution from vehicles and strains the acceptance of today’s car centric mobility. Electrification is the highly touted magic solution, but is it fast and comprehensive enough to solve above mentioned problems? Is society - car owners, automotive industry and governments - willing to pay the high cost for electrified car technology and infrastructure within a short timeframe of 10 to 15 years?

The tighter exhaust emissions standards introduced by governments for light duty vehicles are challenging car manufactures to meet at the same time legal emission limits and fuel efficiency improvements, still providing excellent fun to drive characteristics. The Hybrid and Diesel propulsion systems are two important players on that competition. In this scenario, the 48 V hybridization has the potential to become a cost-effective solution compared to High Voltage systems, outlining a new way to approach the well-known trade-off between CO2 and NOx in Diesels. Aim of this study has been to investigate the benefits offered by a P0 48 V Hybrid system when coupled with a 1.6 L Diesel engine in a 7-seat multi-purpose vehicle.

In this study, the effect of corona discharge on the combustion phenomenon has been made clear. A homogeneous propane-air mixture was used and six equivalence ratios were tested. For generating the positive and negative corona discharge, a non-uniform electric field was applied to the combustion chamber by the needle to plane gap. One or five needle-shaped electrodes were used to change the corona discharge state. When the positive corona discharge was applied, the luminescence from corona with five electrodes was weak as compared with that of one needle-shaped electrode. When the negative corona discharge was applied, the luminescence from corona and combustion were not affected by the number of electrode. When the positive corona discharge was applied by low voltage, the combustion was improved in the case of one needle-shaped electrode, but the index of combustion with one needle-shaped electrode was almost equal to that of five electrodes when the high voltage was applied.

The significance and the number of vehicle safety features enabled via connectivity continue to increase. OnStar, with its automatic airbag notification, was one of the first vehicle safety features that demonstrate the enhanced safety benefits of connectivity. Vehicle connectivity benefits have grown to include remote software updates, data analytics to aid with preventative maintenance and even to theft prevention and recovery. All of these services require available and reliable connectivity. However, except for the airbag notification, none have strict latency requirements. For example, software updates can generally be postponed till reliable connectivity is available. Data required for prognostic use cases can be stored and transmitted at a later time. A new set of use cases are emerging that do demand continuous, reliable and low latency connectivity. For example, remote control of autonomous vehicles may be required in unique situations.

This Standard specifies the test methods, dimensions, and requirements for single-core 60 V cables intended for use in road vehicle applications where the nominal system voltage ≤ 60 V DC (25 V AC). It also specifies additional test methods and/or requirements for 600 V cables intended for use in road vehicle applications where the nominal system voltage is > 60 V DC (25 V AC) to ≤ 600 V DC (600 V AC). Where practical, this standard uses ISO 6722 for test methods, dimensions, and requirements. This standard covers ISO conductor sizes which usually differ from SAE conductor sizes. It also covers the individual cores in multi-core cables. See ISO 6722 for “Temperature Class Ratings”.

A 1200-V, 600-A silicon carbide (SiC) JFET half-bridge module has been developed for drop-in replacement of a 600-V, 600-A IGBT intelligent power module (IPM). Advances in the development of SiC field effect transistors have resulted in reliable high yield devices that can be paralleled and packaged to produce high-voltage and high-current power modules not only competitive with existing IGBT technology but the modules have expanded capabilities. A SiC vertical junction field effect transistor VJFET has been produced with the properties of lower conduction loss, zero tail current, higher thermal conductivity, and higher power density when compared to a similarly rated silicon IGBT or any practical SiC MOSFETs previously reported. Three prototype SiC JFET half-bridge modules with gate drivers have been successfully integrated into a three-phase 30-kW (continuous), 100-kW (intermittent) AC synchronous motor drive designed to control a traction motor in an electric vehicle.

In July 1997, the Pacific Northwest and Alaska Regional Bioenergy Program, in cooperation with several industrial and institutional partners initiated a long-haul 322,000 km (200,000 mile) operational demonstration using a biodiesel and diesel fuel blend in a 324 kW (435 HP), Caterpillar 3406E Engine, and a Kenworth Class 8 heavy duty truck. This project was designed to: develop definitive biodiesel performance information, collect emissions data for both regulated and non-regulated compounds including mutagenic activity, and collect heavy-duty operational engine performance and durability information. To assess long-term engine durability and wear; including injector, valve and port deposit formations; the engine was dismantled for inspection and evaluation at the conclusion of the demonstration. The fuel used was a 50% blend of biodiesel produced from used cooking oil (hydrogenated soy ethyl ester) and 50% 2-D petroleum diesel.

The development of future automotive electronic systems requires new concepts in the software architecture, development methodology and information exchange. At Bosch an XML and MSR based technology is applied to achieve a consistent information handling throughout the entire software development process. This approach enables the tool independent exchange of information and documentation between the involved development partners. This paper presents the software architecture, the specification of software components in XML, the process steps, an example and an exchange scenario with an external development partner.

The recent approval by the SAE Motor Vehicle Council of the serial protocol J1850 is a major milestone in the development of an open and flexible network approach to vehicle wiring. However, it is now necessary to evaluate the practical implementation of the protocol in some real vehicle applications. This paper describes one such exercise which considers a three station installation including the doors and a central body computer function, together with a diagnostic capability. It is, of course, anticipated that this simple system will be extended to include other areas of the vehicle as confidence is gained in its performance and the benefits of system integration are realised.

This paper describes a design of a system that controls the speed and direction of a small DC motor though a network system. This work is important as large numbers of motors are employed inside a modern vehicle. Moreover most of the electronic devices inside a vehicle are networked through a Controller Area Network (CAN). The system uses commands from a CAN node and sends this message through a CAN bus to another CAN node which is controlling the DC motor. The system uses two Phytecs boards (Infineon C505C Microcontrollers based) and communicates through a CAN bus. The system bus is monitored with a Dearborn Protocol Adapter II (DPA-II). The system is broken into four major parts: two CAN nodes, the driver circuitry, and a feedback sensor. This paper provides detailed design, flow chart of the programs and testing of the system.

This SAE Information Report represents an information report on a conceptual ITS architecture and its accompanying protocols from the perspective of Advanced Traveller Information Systems providers and users. While a specific logical and physical architecture for ITS is still in the development stages, this conceptual architecture provides a robust general view of ITS functions and interfaces.

Future avionics systems will have distributed architectures requiring computers and data transfer systems that can perform real-time calculations and are fault tolerant. Previously developed data bus standards such as MIL-STD-1553 are inadequate for these applications. Existing standards will not meet the needs of the future. They are too slow; have functions that are single-point failures; do not take advantage of new technologies such as fiber optics; and have poor efficiency when applied to distributed architectures. To meet the needs of data buses for distributed, real-time, fault-tolerant architectures of the future, a candidate High-Speed Data Bus (HSDB) protocol has been developed by the authors. This paper describes the performance characteristics of the candidate HSDB protocol including the following: Token-passing protocol. Token-passing best meets the needs because it is inherently distributed. Fiber optics implementation.