sync
BIN
Doc/images/EFFICIENCY_PERCENTAGE.jpg
Normal file
After Width: | Height: | Size: 29 KiB |
BIN
Doc/images/RIPPLE_LOADVSFREQ.jpg
Normal file
After Width: | Height: | Size: 28 KiB |
BIN
Doc/images/RIPPLE_LOADVSPKPK.jpg
Normal file
After Width: | Height: | Size: 27 KiB |
BIN
Doc/images/RISETIME_10_MA.png
Normal file
After Width: | Height: | Size: 4.9 KiB |
BIN
Doc/images/RISETIME_50_MA.png
Normal file
After Width: | Height: | Size: 4.9 KiB |
BIN
Doc/images/SNR_LOADVSPKPK.jpg
Normal file
After Width: | Height: | Size: 29 KiB |
BIN
Doc/images/SNR_LOADVSSD.jpg
Normal file
After Width: | Height: | Size: 30 KiB |
BIN
Doc/images/TRANSIENT_RISE_10_MA.jpg
Normal file
After Width: | Height: | Size: 32 KiB |
BIN
Doc/images/TRANSIENT_RISE_50_MA.jpg
Normal file
After Width: | Height: | Size: 33 KiB |
76
Doc/main.tex
@ -42,14 +42,14 @@
|
|||||||
\lipsum[3-4]
|
\lipsum[3-4]
|
||||||
|
|
||||||
|
|
||||||
\section{Methodology}
|
\section{Methodology} \label{section:methodology}
|
||||||
To characterize the system, several tests have been performed. The
|
To characterize the system, several tests have been performed. The
|
||||||
characteristics of interest are the following:
|
characteristics of interest are the following:
|
||||||
\begin{enumerate}[nosep]
|
\begin{enumerate}[nosep]
|
||||||
\item Efficiency
|
\item Efficiency
|
||||||
\item Noise
|
\item Noise
|
||||||
\item Ripple characteristics
|
\item Ripple characteristics
|
||||||
\item Transients
|
\item Start up
|
||||||
\end{enumerate}
|
\end{enumerate}
|
||||||
In this section a test or measurement will be described for each of the above
|
In this section a test or measurement will be described for each of the above
|
||||||
characteristics.
|
characteristics.
|
||||||
@ -60,7 +60,7 @@
|
|||||||
were chosen to give characterize the circuit over a broad range of conditions.
|
were chosen to give characterize the circuit over a broad range of conditions.
|
||||||
|
|
||||||
|
|
||||||
\subsection{Efficiency}
|
\subsection{Efficiency} \label{section:efficiency}
|
||||||
\begin{Figure}
|
\begin{Figure}
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[scale=0.34]{SCHEMATIC_EFFICIENCY.png}
|
\includegraphics[scale=0.34]{SCHEMATIC_EFFICIENCY.png}
|
||||||
@ -94,11 +94,11 @@
|
|||||||
|
|
||||||
\subsubsection{Peak to peak}\label{section:peak_to_peak}
|
\subsubsection{Peak to peak}\label{section:peak_to_peak}
|
||||||
Peak to peak is the simplest way to look at noise. The signal has a stationary
|
Peak to peak is the simplest way to look at noise. The signal has a stationary
|
||||||
mean over the period of 1 millisecond. Thus the highest measured value can be
|
mean over the period of 1 millisecond. Thus, the highest measured value can be
|
||||||
subtracted from the lowest measured value.
|
subtracted from the lowest measured value.
|
||||||
|
|
||||||
|
|
||||||
\subsubsection{Standard Deviation}
|
\subsubsection{Standard Deviation}\label{section:standard_devation}
|
||||||
The second metric used to measure noise was the standard deviation.
|
The second metric used to measure noise was the standard deviation.
|
||||||
Unlike, peak to peak it givesa better impression of the noise over a longer
|
Unlike, peak to peak it givesa better impression of the noise over a longer
|
||||||
signal. SD can be calculated using equation \ref{eq:sd}.
|
signal. SD can be calculated using equation \ref{eq:sd}.
|
||||||
@ -111,7 +111,8 @@
|
|||||||
Where $x[i]$ is each voltage measurement, $\mu$ is the mean of the signal and
|
Where $x[i]$ is each voltage measurement, $\mu$ is the mean of the signal and
|
||||||
$N$ is the total amount of samples.
|
$N$ is the total amount of samples.
|
||||||
|
|
||||||
\subsection{Ripple characteristics}
|
|
||||||
|
\subsection{Ripple characteristics}
|
||||||
\begin{Figure}
|
\begin{Figure}
|
||||||
\centering
|
\centering
|
||||||
\includegraphics[scale=0.5]{RIPPLE.png}
|
\includegraphics[scale=0.5]{RIPPLE.png}
|
||||||
@ -130,7 +131,7 @@
|
|||||||
section \ref{section:peak_to_peak}.
|
section \ref{section:peak_to_peak}.
|
||||||
|
|
||||||
To measure the frequency of the signal using an FFT, it had to be pre-processed
|
To measure the frequency of the signal using an FFT, it had to be pre-processed
|
||||||
first using a Hamming window this eliminates sharp edges at the edge of the
|
first using a Hamming window, this eliminates sharp edges at the edge of the
|
||||||
measurement, causing unwanted frequencies to appear in the frequency domain.
|
measurement, causing unwanted frequencies to appear in the frequency domain.
|
||||||
\begin{equation}
|
\begin{equation}
|
||||||
\label{eq:hamming}
|
\label{eq:hamming}
|
||||||
@ -141,13 +142,68 @@
|
|||||||
sample in the signal can be multiplied by the corresponding value in the window,
|
sample in the signal can be multiplied by the corresponding value in the window,
|
||||||
preparing the signal for the FFT.
|
preparing the signal for the FFT.
|
||||||
|
|
||||||
\subsection{Transients}
|
|
||||||
The last measurements were hocus pocus
|
\subsection{Start up}
|
||||||
|
The last characteristics is the start up, specifically the different rise times
|
||||||
|
under load. The voltage was measured at the output as the supply was turned on.
|
||||||
|
|
||||||
|
Different rise times can be defined. First off, $\tau$ and $2 \tau$ were
|
||||||
|
defined as $63\%$ and $95\%$ respectively. Further more, 'rise time' was defined
|
||||||
|
as $90\%$, a metric used often in control theory.
|
||||||
|
|
||||||
|
One problem that occured during the measurements, is that the aforementioned
|
||||||
|
ripples and noise would cause erroneous readings. As such, the signal was
|
||||||
|
filtered using a low pass filter, reducing the high frequencies from the
|
||||||
|
measurement.
|
||||||
|
|
||||||
|
|
||||||
\section{Results}
|
\section{Results}
|
||||||
\lipsum[1-2]
|
In this section the results from section \ref{section:methodology} will be
|
||||||
|
discussed, as well as discuss some probable causes for unknown or unintended
|
||||||
|
results.
|
||||||
|
|
||||||
|
|
||||||
|
\subsection{Efficiency}
|
||||||
|
\begin{Figure}
|
||||||
|
\centering
|
||||||
|
\includegraphics[scale=0.5]{EFFICIENCY_PERCENTAGE.jpg}
|
||||||
|
\captionof{figure}{WIP}
|
||||||
|
\label{fig:efficiency}
|
||||||
|
\end{Figure}
|
||||||
|
\noindent The results for the efficiency measurements, as described in section
|
||||||
|
\ref{section:efficiency} are displayed in figure \ref{fig:efficiency}.
|
||||||
|
The $7V$ measurements follow a predictable curve, however, the $3.3V$ makes
|
||||||
|
an unexplained jump back to a higher percentage.
|
||||||
|
|
||||||
|
|
||||||
|
\subsection{Noise}
|
||||||
|
\begin{Figure}
|
||||||
|
\centering
|
||||||
|
\includegraphics[scale=0.5]{SNR_LOADVSPKPK.jpg}
|
||||||
|
\captionof{figure}{WIP}
|
||||||
|
\label{fig:noise_pkpk}
|
||||||
|
\end{Figure}
|
||||||
|
\noindent The results for the efficiency measurements, as described in section
|
||||||
|
\ref{section:peak_to_peak} are displayed in figure \ref{fig:noise_pkpk}.
|
||||||
|
The peak to peak voltage is a significant fraction of the output voltage,
|
||||||
|
with $3V$ peaking at $33\%$. It seems there is a relation between peak to
|
||||||
|
peak voltage and the output voltage as well, as $7V$ has more noise than
|
||||||
|
$3.3V$
|
||||||
|
|
||||||
|
\begin{Figure}
|
||||||
|
\centering
|
||||||
|
\includegraphics[scale=0.5]{SNR_LOADVSSD.jpg}
|
||||||
|
\captionof{figure}{WIP}
|
||||||
|
\label{fig:noise_sd}
|
||||||
|
\end{Figure}
|
||||||
|
\noindent The results for the efficiency measurements, as described in section
|
||||||
|
\ref{section:standard_devation} are displayed in figure \ref{fig:noise_sd}.
|
||||||
|
Although the voltage peaks are high, the noise's standard deviation is in the
|
||||||
|
range of millivolts. The trend that a higher output voltage has more noise
|
||||||
|
is continued in this graph.
|
||||||
|
|
||||||
|
\subsection{Ripple}
|
||||||
|
|
||||||
\section{Conclusion}
|
\section{Conclusion}
|
||||||
\lipsum[3-4]
|
\lipsum[3-4]
|
||||||
\end{multicols}
|
\end{multicols}
|
||||||
|