exjobb/rapport/introduction.tex

% !TeX root = main.tex
\chapter{Introduction}\label{cha:intro}

Ta bort när klar

\squareit{
For a product to be put on the market there are many regulations which the product must follow, e.g. electrical safety, material regulations, documentation, quality systems, electromagnetic compatibility (EMC), radio regulations etc. To test products against these requirements in a unified manner, standards are used. A standard defines how a product should be tested and the accepted result that need to be achieved in order to ensure that the product complies with the regulations. There are many standards for many different types of regulations and usually a single product must comply with several of these. It is also common that one standard references another standard, or specific parts of another standard, instead of redefining some tests.

% https://europa.eu/youreurope/business/product/product-rules-specifications/index_en.htm besökt 2019-06-19
}

The ISO 7637 standard, \emph{Road vehicles -- Electrical disturbances from conduction and coupling}, and ISO 16750, \emph{Road vehicles -- Environmental conditions and testing for electrical and electronic equipment}, are international standards that apply to products in road vehicles with a nominal supply voltage of 12 V or 24 V. The standards states, here put in a very condensed form, that the product shall withstand a sufficient amount of disturbances applied to its power supply. The reason for this is that there can be many voltage surges and much noise in a vehicle's power supply lines. In general, the source of disturbances and noise in a vehicle origins from inductance in other devices connected to the power line, the cables and the vehicles alternator in combination with switching of loads or the supply. \cite{iso7637-2, iso16750-2}

\todo[Mention that the standard also addresses emission, but that the report only focuses on immunity]

To test if a product comply with this standard, there is equipment which simulates different events on the power supply. The standard defines the different scenarios, raise and fall times of test pulses, repetition times etc. It also defines the functional requirements of the equipment during these tests for what is considered a passed or a failed test. \cite{iso7637-2, iso16750-2}

\section{Motivation}

The standard defines all the timing requirements that must be met, and also specifies the load conditions for which the requirements apply \cite{iso7637-2}. From time to time the standards are revised, which might alter the requirements form the previous versions of the standard. New equipment is guaranteed by its manufacturer to do the tests according to the latest standard, as long as it is regularly sent in for calibration and maintenance. New equipment costs a great amount of money and might not even be affordable by smaller test labs, and can thus inhibit labs from performing tests for this standard.

An appealing alternative would be the possibility to reuse the test equipment that was used along with the older revision of the standard, as long as it is capable of performing sufficient tests reliable. For this to be of any value the test equipment must be verified in some way to be able to guarantee that the tests are performed according to the new standard.

The old ISO 7637-2:2004 standard got revised to 7637-2:2011 and some parts were 

\section{Aim}

The goal of this work is to investigate the potential of reusing test equipment made for an old standard, with the newer revised version of that standard, and how to assure that the test results are reliable.

The verification of the system is desired to be automated. This automated verification procedure is also part of the goal.

\section{Research questions}

The following questions will be answered in this paper:

\begin{itemize}
    \item{Can test equipment made for ISO 7637-2:2004, be used for testing compliance against ISO 7637-2:2011, the newer version of the standard?}
    \item{If it can; What considerations must be made to allow for automating the test and verification process?}
    \item{If it can't; What causes the failure, and what possible fixes can be made to make the equipment usable for the newer standard?}

    % \item{------- OLD STUFF FOLLOW \todo[Remove the old stuff]}
    % \item{How should the test equipment be verified to give a robust result?}
    % \item{How much differences are there in a real implementation compared to a simulated system?}
    %\item{What is the best way of acquiring a high voltage signal with high frequency components?}
    %\item{What is the best way to verify the time-domain parameters of the signal?}
    % \item{------- OLD STUFF FOLLOW \todo[Remove the old stuff]}
    % 
    % \item{Is the reused system more cost effective than investing and maintaining a new test system?}
\end{itemize}

\section{Delimitations}
This paper only compares the standard ISO 7637-2:2004 to ISO 7637-2:2011 and ISO~16750-2:2012, because these are the most recent versions of the standards.

This paper only considers Pulse 1, Pulse 2a, Pulse 3a, Pulse 3b and Load dump A. The main reason being that these are the pulses that the available equipment can generate, but also that these pulses share many properties and the method of analysing them will probably be very similar.

This paper only considers the following test equipment for the real implementation that is available for this project:

\begin{table}[H]
    \begin{tabularx}{0.6\textwidth}{|l|X|}
        \hline
        \textbf{Model} &\textbf{Description}\\
        \hline
        EFT 200A    &Burst generator\\
        \hline
        MPG 200B    &Micropulse generator\\
        \hline
        LD 200B    &Load dump generator\\
        \hline
        CNA 200B    &Connection Network\\
        \hline
    \end{tabularx}
\end{table}

%The methods used might be applicable to other similar standards and equipment.

\section{Report structure}

\todo[fyll i upplägg när det väl är klart]