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\textbf{Preloading Integral}\\
A rising edge at the \emph{Enable} inport enables the controller and preloads the integral.\\
\newline One may choose from two options how to preload the integral value:
\begin{itemize}
	\item Preload the integral from the \emph{Init} inport.
	\item Preload the integral such that the first output of the controller matches the current value at the \emph{Init} inport.
	\newline This option allows controller switching without disturbing the control.
\end{itemize}

\paragraph{Note:}Each fixed point implementation uses the next higher integer data type for the integral value storage variable.

\noindent
\textbf{Transfer function} (zero-order hold discretization method):\\
When the block is enabled, the PI controller realizes the following transfer function:
Transfer function (zero-order hold discretization method):
\begin{eqnarray*}
	G(z) = K_{\mathrm{p}} + K_{\mathrm{i}}T_{\mathrm{s}}\frac{1}{z-1}
\end{eqnarray*}

\textbf{Anti Wind-Up}\\
The implemented anti wind-up method is clamping. 
If the output signal out exceeds the upper or lower limit value, 
which is given by the inport max and the inport min, the integrator is \newline
clamped if the controller input would increase the saturation even further. \newline


\paragraph{Developer note:} The source code of this block is used for block \textit{PI}.
