Automotive Electromagnetic Compatibility

Prediction and Analysis of Parasitic
Components in Conductor Layouts
Sabine Alexandersson
Doctoral Dissertation in Industrial Electrical Engineering
Department of Industrial Electrical Engineering and Automation
2008-LUND UNIVERSITY

Abstract
The electronics in the automotive industry is facing a new era where safety
critical functions are electrified, as for example drive-by-wire technology. At
the same time as the number of electrical loads in the vehicles is increasing,
the time to market is decreasing. Full scale prototypes of a vehicle are often
only available at a late stage in the development process where changes are
rather costly. This implies that prediction and simulation of a system are of
importance and are useful already at an early stage of the development
process. There are economic benefits that can be gained by prediction and
simulation of the system such as: reduction of time to market, virtual tests,
virtual prototypes and optimization of electronic circuits with respect to
safety margins of filters.
The high number of electrical loads in the vehicle leads to different cable
harnesses routed along the body and chassis of the vehicle. These cable
harnesses will contain both power conductors and communication
conductors, routed close together. When conductors are routed close to each
other, a signal on one conductor can interfere with the signal on another
conductor. This phenomenon is called crosstalk.
Crosstalk can increase the noise levels, create unplanned spikes or destroy
data on nearby conductors. Hence it should always be a prime suspect in an
electromagnetic interference investigation or a candidate for prediction.
Crosstalk between two conductors is coupled by the mutual inductance and
capacitance. When these parameters are known, the crosstalk can be
estimated by using a circuit simulation.
The mutual inductance and capacitance between the conductors as well as the
self inductance and capacitance of each conductor depend on the
surrounding environment. This implies that the conductor layout is an
important factor when it comes to designing a system that is robust against
crosstalk.
Chapter 2
Automotive electromagnetic compatibility

Automatic modelling of Power Electronic Converter, Average model

Proceedings 7th Modelica Conference, Como, Italy, Sep. 20-22, 2009
Loig ALLAIN
LMS
La Cité Internationale, 84 quai Charles de
Gaulle,F- 69006 LYON
loig.allain@lmsintl.com
Automatic modelling of Power Electronic Converter, Average model
construction and Modelica model generation

KTH School of Electrical Engineering.

Welcome to Electrical Machines and Power Electronics
We welcome you to the webpage of the Electrical Machines and Power Electronics (EME) department at the KTH School of Electrical Engineering.
The major research areas at EME are electrical machines and drives, power electronics and control, and electric traction.
In house we have a large and well equipped laboratory, where most of the practical education and experimental research is performed.
Read more about our research and the education we provide, or learn more about EME and the people who work here, by exploring our website. Students will find information about courses in electrical machines and power electronics and suggestions for thesis work.

Thermal modeling of a medium frequency transformer

Author:	Kalle Ilves
Title:	Thermal Modelling of a Medium Frequency Transformer
School:	Royal Institute of Technology
Date:	March 2009
Type:	MastersThesis

Abstract
This thesis covers thermal modeling of a medium freuqency transformer. The
geometry of the transformer and the thermal properties of the di erent parts
are used to derive thermal resistances that can be put together in an equivalent
circuit describing the thermal system. The transformer is immersed in oil and
it is found that convective heat transfer through the oil must be included in the
model. The dynamic behaviour of the transformer is also modeled by including
thermal capacitances in the circuit.
The model is evaluated by measuring the primary winding and core temperature
while the transformer is heated. The primary winding temperature is measured
by measuring its electical resistance. The chosen method is discussed along
with the di erence between the measured and estimated response of the
thermal system

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Has the world really discovered the advantages of Brazilian automotive engineering?

By Thiago Struminski, Industry Analyst, Latin America -FROST & SULLIVAN

The Brazilian automotive engineering has a long standing tradition, it exists for over 50 years and the country unveils its 3rd generation of automotive engineers. Its competence was built by vehicle producers which over the 50s and 80s locally manufactured cars, long gone from their production plans in Europe and the U.S and required several adaptations for the local market. It is the case of GM's Opala model. The specific conditions of Brazil drove the need to search for unique solutions and created spaces for local development activities. The country has a wide territory, poor road conditions and in terms of temperature; the south of Brazil reaches -5 Celsius, and the north +40 Celsius. Vehicle producers have to take all of that into account when projecting the durability of a vehicle body. Therefore, the utilization of different materials is one of the ingredients to give a local face to the Brazilian Automotive Engineering. Later on, the development activities evolved to the derivation of vehicles conceived abroad such as the pick up Corsa and the Astra Sedan, originated from Germany.

Throughout its history, creativity and capacity to offer low cost solutions have always walked side to side with local automotive professionals. The local engineering culture was formed under strong cost pressures and requirements to increase productivity levels with limited resources. Such scenario has contributed to another very important differential: flexibility. The speed in terms of capturing the new trends and bringing it to new models is certainly a major competitive advantage in a time which product life cycles decrease with strong intensity.

The Brazilian automotive industry has been the pioneer in producing small pick ups and 1.0 liter engines. The latter has amazingly pushed forward the sales of popular vehicles in the early 90s and still accounts for 52 percent of all cars sold in the country.

However, the flagship automotive technology is related to alternative fuels. During the 70s, the oil crisis forced the Brazilian government to find solutions in order to diversify its energy matrix. The way out was to introduce gasoline blended with a high volume of ethanol; in order to foster the development of straight ethanol fueled vehicles. Later on in 2003, important suppliers such as Magneti Marelli, and Bosch, through some special electronic sensors developed in Brazil the flex fuel technology. In practical terms, the flex fuel allows the choice of fuel (at each vehicle refueling) according to characteristics of price, quality, performance or even fuel availability. Soon after its introduction in the Brazilian market, flex fuel vehicles reached 86 percent of market share in only four years. At the moment, local efforts are concentrated on Biodiesel which is already obligatory by Brazilian legislation.

In such a spirit, Brazil has successfully evolved from the tropicalization of products designed elsewhere, to the unit by unit construction of new vehicles. Finally, the Brazilian automotive industry has achieved a status of a global platform designer.

A critical point for the Brazilian automotive industry would be to speed up the process of involving engineers within development activities. Currently to capacitate a project coordinator to the automotive industry takes an average of 8 years. In order to be 50 percent more effective the ideal target is to reach a 2-3 year level.

The industry needs to enhance the attractiveness of working for the automotive industry and the engineering activity itself. Local associations such as SAE Brazil are trying to incentive newcomers at the very bottom of the education system creating technical courses for youngsters and fostering a culture of technology. It is essential for a country which lags behind in its educational system. Most developed countries have an average of 25 engineers per every 1000 thousand inhabitants; Brazil has much lower average than that. The percentage of graduated Brazilian Engineers in comparison to all graduated University students is also below international standard.

There are about 13,000 engineers engaged on the Brazilian automotive industry. The movement private sector/University has intensified over the recent years and promoted specific success stories such as GM/Politecnica, Ford/Unicamp, Fiat/PUC Minas and UFSC, but still has a lot to improve. Around 68 percent of the research groups involved in automotive are concentrated on the South/Southeast region. All the vehicle producer/University associations draw the example of the link Embraer/ITA. The Brazilian airplane manufacturer was the first local company to really speed up the development of specialized engineers giving them interesting career opportunities. Working with more than 4,000 engineers, with the assistance of the University it has manage to create a very innovative culture, allowing them to produce the latest technology and become world reference in terms of regional jets. As the example is followed by the automotive industry, results are starting to appear.

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