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@@ -26,20 +26,20 @@ To get hold of a copy of a standard, one need to buy it from ISO or one of its r
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\textbf{The ISO~7637 standard}, \emph{Road vehicles — Electrical disturbances from
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conduction and coupling}, concerns the electrical environment in road vehicles. The standard consists of, at the time of writing, four parts.
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-Part 1, \emph{Definitions and general considerations}, defines some abbreviations and technical terms that are used throughout the standard. It also describes the scope of where the standard is intended to be applied. \cite{iso-7637-1}
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+Part 1, \emph{Definitions and general considerations}, defines some abbreviations and technical terms that are used throughout the standard. It also describes the scope of where the standard is intended to be applied. \cite{iso_7637_1}
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-Part 2, \emph{Electrical transient conduction along supply lines only}, defines the test procedures related to disturbances that are carried along the supply lines of a product. Both emission, disturbances created by the DUT, and immunity, the DUT's capability to withstand disturbances, are covered. This part defines the test pulses, and the verification of the same, that are of interest to this project. \cite{iso-7637-2}
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+Part 2, \emph{Electrical transient conduction along supply lines only}, defines the test procedures related to disturbances that are carried along the supply lines of a product. Both emission, disturbances created by the DUT, and immunity, the DUT's capability to withstand disturbances, are covered. This part defines the test pulses, and the verification of the same, that are of interest to this project. \cite{iso_7637_2}
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-Part 3, \emph{Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines}, defines immunity tests against disturbances on other interfaces that the power supply. It focuses on test setups and different ways of coupling the signals. \cite{iso-7637-3}
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+Part 3, \emph{Electrical transient transmission by capacitive and inductive coupling via lines other than supply lines}, defines immunity tests against disturbances on other interfaces that the power supply. It focuses on test setups and different ways of coupling the signals. \cite{iso_7637_3}
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-Part 5, \emph{Enhanced definitions and verification methods for harmonization of pulse generators according to ISO~7637}, proposes an alternative verification method of the test pulses defined in ISO~7637-2. The main difference from the method described in ISO~7637-2 is that $U_A$ should not only be 0~V during the verification, but also be set to $U_N$. This will not be considered deeply in this report, since it is only a proposal and makes the verification equipment more difficult. \cite{iso-7637-5}
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+Part 5, \emph{Enhanced definitions and verification methods for harmonization of pulse generators according to ISO~7637}, proposes an alternative verification method of the test pulses defined in ISO~7637-2. The main difference from the method described in ISO~7637-2 is that $U_A$ should not only be 0~V during the verification, but also be set to $U_N$. This will not be considered deeply in this report, since it is only a proposal and makes the verification equipment more difficult. \cite{iso_7637_5}
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The ISO~16750, \emph{Road vehicles -- Environmental conditions and testing for electrical and electronic equipment}, concerns different environmental factors that a product might face in a vehicle, such as mechanical shocks, temperature changes and acids. Part 2, \emph{Electrical Loads}, of the standard deals with some electrical aspects that was previously part of the ISO~7637 standard. This is the only part of ISO~16750 that will be considered.
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-\cite{iso-16750-1, iso-16750-2}
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+\cite{iso-16750-1, iso_16750_2}
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\section{Test pulses}
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-All test pulses defined in ISO~7637 and ISO~16750 are supposed to simulate events that can occur in a real vehicle's electrical environment, that products must be able to withstand. The properties of these test pulses are well defined, to allow for unified testing regardless of which test lab that performs the test. In the real world, however, the disturbances might of course differ from the test pulses since a real case environment is not controlled. \cite{iso-7637-2,iso-16750-2, comparison_iso_7637_real_world}
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+All test pulses defined in ISO~7637 and ISO~16750 are supposed to simulate events that can occur in a real vehicle's electrical environment, that products must be able to withstand. The properties of these test pulses are well defined, to allow for unified testing regardless of which test lab that performs the test. In the real world, however, the disturbances might of course differ from the test pulses since a real case environment is not controlled. \cite{iso_7637_2,iso_16750_2, comparison_iso_7637_real_world}
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The test pulses of interest defined in ISO~7637 are denoted \emph{Test pulse 1}, \emph{Test pulse 2a}, \emph{Test pulse 3a} and \emph{Test pulse 3b}. The test pulse of interest defined in ISO~16750 is denoted \emph{Load dump Test A}. There are more pulses and tests defined in these standards, but those are not in the scope of this thesis.
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@@ -62,7 +62,7 @@ This pulse simulates the event of a load, parallel to the DUT, is disconnected.
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\todo[Två bilder, en på kurvan och en på kretsen som orsakar den. En tabell med parametervärden.]
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\subsection{Test pulse 3a and 3b}
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-Test pulse 3a and 3b simulates transients ``which occur as a result of the switching process'' as stated in \cite{iso-7637-2}. The formulation is not very clear, but is interperted and explained by Frazier and Alles \cite{comparison_iso_7637_real_world} to be the result of a mechanical switch brekaking an inductive load. These transients are very short, compared to the other pulses, and the repetition time is very short. The pulses are sent in bursts, grouping a number of pulses together and separating groups by a fixed time.
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+Test pulse 3a and 3b simulates transients ``which occur as a result of the switching process'' as stated in \cite{iso_7637_2}. The formulation is not very clear, but is interperted and explained by Frazier and Alles \cite{comparison_iso_7637_real_world} to be the result of a mechanical switch brekaking an inductive load. These transients are very short, compared to the other pulses, and the repetition time is very short. The pulses are sent in bursts, grouping a number of pulses together and separating groups by a fixed time.
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These pulses contain high frequency components, up to 100~MHz, and special care must be taken when running tests with them as well as when verifying them.
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@@ -82,7 +82,7 @@ During a test, the nominal voltage is first applied between the plus and minus t
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\todo[Snygg bild på uppkoppling och kopplingsnätverk.].
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\subsection{Mathematical description}
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-All of the test pulses applied to the vehicle equipment can individually be described mathematically by variations of the double exponential function shown in \autoref{eq:doubleexp} and \autoref{fig:doubleexp}. The properties of interest, the ones which are specified in the standards, are the surge voltage $ U_s $, the rise time $ t_r $, the duration $ t_d $ and the repetition time $ t_1 $. \cite{iso-7637-2}
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+All of the test pulses applied to the vehicle equipment can individually be described mathematically by variations of the double exponential function shown in \autoref{eq:doubleexp} and \autoref{fig:doubleexp}. The properties of interest, the ones which are specified in the standards, are the surge voltage $ U_s $, the rise time $ t_r $, the duration $ t_d $ and the repetition time $ t_1 $. \cite{iso_7637_2}
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How $k$, $\alpha$ and $beta$ are related to these properties will be described in more detail in \autoref{sec:double_exponential_function}.
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@@ -106,11 +106,11 @@ How $k$, $\alpha$ and $beta$ are related to these properties will be described i
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\end{figure}
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\subsection{Verification}
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-The test pulses are to be verified before they are applied to the DUT. The voltage levels and the timings are to be measured, with and without a matched load attached $R_L$ = $R_i$. The standard omits the rise time constraint when the load is attached, except for pulse 3a and 3b. \cite{iso-7637-2}
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+The test pulses are to be verified before they are applied to the DUT. The voltage levels and the timings are to be measured, with and without a matched load attached $R_L$ = $R_i$. The standard omits the rise time constraint when the load is attached, except for pulse 3a and 3b. \cite{iso_7637_2}
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-The verification is to be conducted with $U_A$ set to 0. There is, however, a proposal to set $U_A$ to the actual nominal voltage during the verification process, as the behaviour of the pulse generators has proven differ in this case \cite{iso-7637-5}. In this project $U_A = 0$ will be used.
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+The verification is to be conducted with $U_A$ set to 0. There is, however, a proposal to set $U_A$ to the actual nominal voltage during the verification process, as the behaviour of the pulse generators has proven differ in this case \cite{iso_7637_5}. In this project $U_A = 0$ will be used.
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-The limits, and tolerances, for the pulses are summarised in \autoref{tab:verification-list}. The matched loads are to be within 1\% of the nominal value. \cite{iso-7637-2}
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+The limits, and tolerances, for the pulses are summarised in \autoref{tab:verification-list}. The matched loads are to be within 1\% of the nominal value. \cite{iso_7637_2}
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\begin{table}[h]
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\begin{adjustbox}{width=\columnwidth,center}
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Jonatan Gezelius