From 07dfbd56db0f683827470f7ebf77e2248adaf19e Mon Sep 17 00:00:00 2001
From: Michael Wetter <mwetter@lbl.gov>
Date: Mon, 18 Nov 2024 16:51:47 +0000
Subject: [PATCH] Change initialization of electrical load (#4049)

This closes #4048. It also merges minor changes from IBPSA.
---
 .../Airflow/Multizone/BaseClasses/DoorDiscretized.mo     | 5 +++++
 Buildings/Electrical/DC/Loads/Resistor.mo                | 2 +-
 Buildings/Electrical/Interfaces/Load.mo                  | 9 ++++++++-
 Buildings/Resources/Scripts/BuildingsPy/conf.yml         | 4 ----
 4 files changed, 14 insertions(+), 6 deletions(-)
diff --git a/Buildings/Airflow/Multizone/BaseClasses/DoorDiscretized.mo b/Buildings/Airflow/Multizone/BaseClasses/DoorDiscretized.mo
index c05bfe92561..c0b6666d3cd 100644
--- a/Buildings/Airflow/Multizone/BaseClasses/DoorDiscretized.mo
+++ b/Buildings/Airflow/Multizone/BaseClasses/DoorDiscretized.mo
@@ -118,6 +118,11 @@ using the model for a door that can be open or closed.
 revisions="<html>
 <ul>
 <li>
+October 29, 2024, by Klaas De Jonge:<br/>
+Unprotected <code>dh</code> and changed prefixes of <code>dh</code>,<code>hAg</code> and <code>hBg</code> to <code>input</code>.<br/>
+This is for <a href=\"https://github.com/ibpsa/modelica-ibpsa/issues/1935\">#1935</a>.
+</li>
+<li>
 January 8, 2019, by Michael Wetter:<br/>
 Moved parameter <code>CD</code> from
 <a href=\"modelica://Buildings.Airflow.Multizone.BaseClasses.DoorDiscretized\">
diff --git a/Buildings/Electrical/DC/Loads/Resistor.mo b/Buildings/Electrical/DC/Loads/Resistor.mo
index 8a20ae2f356..16bef82695c 100644
--- a/Buildings/Electrical/DC/Loads/Resistor.mo
+++ b/Buildings/Electrical/DC/Loads/Resistor.mo
@@ -47,7 +47,7 @@ The temperature <i>T</i> is the temperature of the heat port if <code>useHeatPor
 <li>November 2, 2024, by Michael Wetter:<br/>
 Changed guarding against division by zero.<br/>
 This is for
-<a href=\"https://github.com/lbl-srg/modelica-buildings/issues/4032\">Buildings, #4032</a>.
+<a href=\"https://github.com/lbl-srg/modelica-buildings/issues/4032\">Buildings #4032</a>.
 </li>
 <li>November 3, 2015, by Michael Wetter:<br/>
 Set default value for <code>P_nominal</code> to avoid an error when translating
diff --git a/Buildings/Electrical/Interfaces/Load.mo b/Buildings/Electrical/Interfaces/Load.mo
index 63efea7234b..5a25c2a9888 100644
--- a/Buildings/Electrical/Interfaces/Load.mo
+++ b/Buildings/Electrical/Interfaces/Load.mo
@@ -22,7 +22,7 @@ model Load "Partial model for a generic load"
            or linearized)));
   parameter Buildings.Electrical.Types.InitMode initMode(
   min=Buildings.Electrical.Types.InitMode.zero_current,
-  max=Buildings.Electrical.Types.InitMode.linearized) = Buildings.Electrical.Types.InitMode.zero_current
+  max=Buildings.Electrical.Types.InitMode.linearized) = Buildings.Electrical.Types.InitMode.linearized
     "Initialization mode for homotopy operator"  annotation(Dialog(tab = "Initialization"));
 
   Modelica.Units.SI.Voltage v[:](start=PhaseSystem.phaseVoltages(V_nominal)) =
@@ -113,6 +113,13 @@ equation
   annotation ( Documentation(revisions="<html>
 <ul>
 <li>
+November 14, 2024, by Michael Wetter:<br/>
+Changed default initialization method to using linearized model rather than zero current, as
+the latter causes a division by zero in OpenModelica during the homotopy initialization.<br/>
+This is for
+<a href=\"https://github.com/lbl-srg/modelica-buildings/issues/4048\">Buildings, #4048</a>.
+</li>
+<li>
 January 30, 2019, by Michael Wetter:<br/>
 Set start value for <code>P</code>.
 </li>
diff --git a/Buildings/Resources/Scripts/BuildingsPy/conf.yml b/Buildings/Resources/Scripts/BuildingsPy/conf.yml
index d5cea08776a..34e6b3214d0 100644
--- a/Buildings/Resources/Scripts/BuildingsPy/conf.yml
+++ b/Buildings/Resources/Scripts/BuildingsPy/conf.yml
@@ -120,10 +120,6 @@
   openmodelica:
     comment: simulation terminated by an assertion at initialization.
     simulate: false
-- model_name: Buildings.Electrical.DC.Loads.Examples.LinearizedLoad
-  openmodelica:
-    comment: '''omc'' caused ''simulation terminated by an assertion at initialization''.'
-    simulate: false
 - model_name: Buildings.Examples.DualFanDualDuct.ClosedLoop
   optimica:
     comment: CVode and Radau5ODE hang since https://github.com/lbl-srg/modelica-buildings/pull/3109, likely because Xi rather than mXi is a state
