Set nominal attribute for terminal voltage (#2952)

* Set nominal attribute This is needed for convergence with Dymola 2023 beta3 of Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepUp.DD. For #2951 * Set nominal values for terminal voltage This allows Dymola 2023 beta3 to solve Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepDown.DY and Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepUp.DD
lbl-srg · Apr 8, 2022 · b57e64c · b57e64c
1 parent 3050077
commit b57e64c
Show file tree

Hide file tree

Showing 12 changed files with 162 additions and 76 deletions.
diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/Line.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/Line.mo
@@ -1,6 +1,8 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model Line "Model of an electrical line without neutral cable"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
   extends Buildings.Electrical.Transmission.BaseClasses.PartialBaseLine(
   V_nominal(start = 480),
   commercialCable = Buildings.Electrical.Transmission.Functions.selectCable_low(P_nominal, V_nominal));
@@ -104,6 +106,10 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 October 6, 2014, by Marco Bonvini:<br/>
 Revised documentation and model.
 </li>

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/Line_N.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/Line_N.mo
@@ -1,6 +1,8 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model Line_N "Model of an electrical line with neutral cable"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
   extends Buildings.Electrical.Transmission.BaseClasses.PartialBaseLine(
   V_nominal(start = 480),
   commercialCable = Buildings.Electrical.Transmission.Functions.selectCable_low(P_nominal, V_nominal));
@@ -126,6 +128,10 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 October 6, 2014, by Marco Bonvini:<br/>
 Revised documentation and model.
 </li>

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRL.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRL.mo
@@ -1,7 +1,9 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortMatrixRL
   "Model of an RL line parameterized with impedance matrices"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
   parameter Modelica.Units.SI.Voltage V_nominal(min=0, start=480)
     "Nominal voltage (V_nominal >= 0)"
     annotation (Evaluate=true, Dialog(group="Nominal conditions"));
@@ -24,11 +26,11 @@ model TwoPortMatrixRL
   final parameter Modelica.Units.SI.Impedance[2] Z32=Z23
     "Element [3,1] of impedance matrix";
 
-  Modelica.Units.SI.Current i1[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i1[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[1].i "Current in line 1";
-  Modelica.Units.SI.Current i2[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i2[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[2].i "Current in line 2";
-  Modelica.Units.SI.Current i3[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i3[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[3].i "Current in line 3";
   Modelica.Units.SI.Voltage v1_n[2](
     start=Buildings.Electrical.PhaseSystems.OnePhase.phaseVoltages(V_nominal/
@@ -108,6 +110,15 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2022, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminals.
+This is required for
+<a href=\"modelica://Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepUp.DD\">
+Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepUp.DD</a>
+to converge with Dymola 2023 beta3.
+Inspecting the homotopy trajectory showed that this variable diverged to an unreasonable value.
+</li>
+<li>
 November 28, 2016, by Michael Wetter:<br/>
 Removed zero start value for currents <code>i1</code>, <code>i2</code> and
 <code>i3</code>.

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRLC.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRLC.mo
@@ -1,7 +1,9 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortMatrixRLC
   "PI model of a line parameterized with impedance and admittance matrices"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
   parameter Modelica.Units.SI.Voltage V_nominal(min=0, start=480)
     "Nominal voltage (V_nominal >= 0)"
     annotation (Evaluate=true, Dialog(group="Nominal conditions"));
@@ -163,6 +165,10 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 November 28, 2016, by Michael Wetter:<br/>
 Made current and voltage public to allow setting start values.<br/>
 This is for

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRLC_N.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRLC_N.mo
@@ -1,7 +1,10 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortMatrixRLC_N
   "PI model of a line parameterized with impedance and admittance matrices and neutral line"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
+
   parameter Modelica.Units.SI.Voltage V_nominal(min=0, start=480)
     "Nominal voltage (V_nominal >= 0)"
     annotation (Evaluate=true, Dialog(group="Nominal conditions"));
@@ -221,6 +224,10 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 November 28, 2016, by Michael Wetter:<br/>
 Made current and voltage public to allow setting start values.<br/>
 This is for

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRL_N.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortMatrixRL_N.mo
@@ -1,7 +1,10 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortMatrixRL_N
   "Model of an RL line parameterized with impedance matrices and neutral line"
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
+
   parameter Modelica.Units.SI.Voltage V_nominal(min=0, start=480)
     "Nominal voltage (V_nominal >= 0)"
     annotation (Evaluate=true, Dialog(group="Nominal conditions"));
@@ -38,13 +41,13 @@ model TwoPortMatrixRL_N
   final parameter Modelica.Units.SI.Impedance[2] Z43=Z34
     "Element [4,3] of impedance matrix";
 
-  Modelica.Units.SI.Current i1[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i1[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[1].i "Current in line 1";
-  Modelica.Units.SI.Current i2[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i2[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[2].i "Current in line 2";
-  Modelica.Units.SI.Current i3[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i3[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[3].i "Current in line 3";
-  Modelica.Units.SI.Current i4[2](each stateSelect=StateSelect.prefer) =
+  Modelica.Units.SI.Current i4[2](each stateSelect=StateSelect.prefer)=
     terminal_n.phase[4].i "Current in line 4 (neutral)";
   Modelica.Units.SI.Voltage v1_n[2](
     start=Buildings.Electrical.PhaseSystems.OnePhase.phaseVoltages(V_nominal/
@@ -133,6 +136,10 @@ equation
     Documentation(revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 November 28, 2016, by Michael Wetter:<br/>
 Made current and voltage public to allow setting start values.<br/>
 This is for

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortRLC.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortRLC.mo
@@ -1,7 +1,10 @@
 within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortRLC "Model of an RLC element with two electrical ports"
   extends Modelica.Electrical.Analog.Interfaces.ConditionalHeatPort;
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
+
   parameter Modelica.Units.SI.Resistance R "Resistance at temperature T_ref";
   parameter Modelica.Units.SI.Capacitance C "Capacity";
   parameter Modelica.Units.SI.Inductance L "Inductance";
@@ -200,6 +203,10 @@ to <i>L/3</i>, a resistance equal to <i>R/3</i> and a capacity equal to
 </html>", revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 September 17, 2016, by Michael Wetter:<br/>
 Corrected wrong annotation to avoid an error in the pedantic model check
 in Dymola 2017 FD01 beta2.<br/>

diff --git a/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortRLC_N.mo b/Buildings/Electrical/AC/ThreePhasesUnbalanced/Lines/TwoPortRLC_N.mo
@@ -2,7 +2,10 @@ within Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines;
 model TwoPortRLC_N
   "Model of an RLC element with two electrical ports and neutral line cable"
   extends Modelica.Electrical.Analog.Interfaces.ConditionalHeatPort;
-  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N;
+  extends Buildings.Electrical.AC.ThreePhasesUnbalanced.Interfaces.TwoPort_N(
+    terminal_p(phase(v(each nominal = V_nominal))),
+    terminal_n(phase(v(each nominal = V_nominal))));
+
   parameter Modelica.Units.SI.Resistance R "Resistance at temperature T_ref";
   parameter Modelica.Units.SI.Resistance Rn
     "Resistance of neutral cable at temperature T_ref";
@@ -232,6 +235,10 @@ The resistance, capacitance and inductance of the neutral cable are defined sepa
 </html>", revisions="<html>
 <ul>
 <li>
+April 5, 2023, by Michael Wetter:<br/>
+Set nominal attribute for voltage at terminal.
+</li>
+<li>
 September 17, 2016, by Michael Wetter:<br/>
 Corrected wrong annotation to avoid an error in the pedantic model check
 in Dymola 2017 FD01 beta2.<br/>

diff --git a/...al_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepDown_DD.txt b/...al_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepDown_DD.txt
@@ -1,22 +1,31 @@
-last-generated=2015-05-08
-statistics-initialization={'numerical Jacobians': '0', 'nonlinear': '18'}
-statistics-simulation={'numerical Jacobians': '0', 'nonlinear': ' ', 'linear': ' '}
-err_V3[3]=[-0.01523122191429138184, -0.01523122191429138184]
-err_V4[1]=[0.00479656504467129707, 0.00479656504467129707]
-err_V4[3]=[-0.2485357820987701416, -0.2485357820987701416]
-err_V4[2]=[-0.14799730479717254639, -0.14799730479717254639]
-err_V2[3]=[0.23235963284969329834, 0.23235963284969329834]
-err_V2[1]=[-0.29025688767433166504, -0.29025688767433166504]
-time=[0., 1.]
-err_V3[2]=[0.31813293695449829102, 0.31813293695449829102]
-err_V2[2]=[-0.43819639086723327637, -0.43819639086723327637]
-err_V3[1]=[-0.42029714584350585938, -0.42029714584350585938]
-err_Theta4[1]=[-0.00045463835704140365, -0.00045463835704140365]
-err_Theta4[3]=[-0.00093711778754368424, -0.00093711778754368424]
-err_Theta3[2]=[-0.00063980644335970283, -0.00063980644335970283]
-err_Theta4[2]=[0.00070442043943330646, 0.00070442043943330646]
-err_Theta3[3]=[-0.00036810690653510392, -0.00036810690653510392]
-err_Theta3[1]=[-0.00018250738503411412, -0.00018250738503411412]
-err_Theta2[3]=[0.00041117277578450739, 0.00041117277578450739]
-err_Theta2[2]=[0.00005636638888972811, 0.00005636638888972811]
-err_Theta2[1]=[0.00040643525426276028, 0.00040643525426276028]
+last-generated=2022-04-08
+statistics-initialization=
+{
+  "nonlinear": "18",
+  "numerical Jacobians": "0"
+}
+statistics-simulation=
+{
+  "linear": " ",
+  "nonlinear": " ",
+  "numerical Jacobians": "0"
+}
+time=[0e+00, 1e+00]
+err_V2[1]=[-2.902640104293823e-01, -2.902640104293823e-01]
+err_V2[2]=[-4.382274746894836e-01, -4.382274746894836e-01]
+err_V2[3]=[2.321996241807938e-01, 2.321996241807938e-01]
+err_V3[1]=[-4.1964191198349e-01, -4.1964191198349e-01]
+err_V3[2]=[3.180856704711914e-01, 3.180856704711914e-01]
+err_V3[3]=[-1.450289878994226e-02, -1.450289878994226e-02]
+err_V4[1]=[-7.467531133443117e-03, -7.467531133443117e-03]
+err_V4[2]=[-1.494017392396927e-01, -1.494017392396927e-01]
+err_V4[3]=[-2.524669468402863e-01, -2.524669468402863e-01]
+err_Theta2[1]=[4.064390668645501e-04, 4.064390668645501e-04]
+err_Theta2[2]=[5.635702837025747e-05, 5.635702837025747e-05]
+err_Theta2[3]=[4.1117166983895e-04, 4.1117166983895e-04]
+err_Theta3[1]=[-1.825740473577753e-04, -1.825740473577753e-04]
+err_Theta3[2]=[-6.397475954145193e-04, -6.397475954145193e-04]
+err_Theta3[3]=[-3.679547517094761e-04, -3.679547517094761e-04]
+err_Theta4[1]=[-4.529835132416338e-04, -4.529835132416338e-04]
+err_Theta4[2]=[7.069333805702627e-04, 7.069333805702627e-04]
+err_Theta4[3]=[-9.378492250107229e-04, -9.378492250107229e-04]
diff --git a/...al_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepDown_YD.txt b/...al_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepDown_YD.txt
@@ -1,4 +1,4 @@
-last-generated=2021-04-07
+last-generated=2022-04-08
 statistics-initialization=
 {
   "nonlinear": "14",
@@ -11,21 +11,21 @@ statistics-simulation=
   "numerical Jacobians": "0"
 }
 time=[0e+00, 1e+00]
-err_V2[1]=[-2.230579555034637e-01, -2.230579555034637e-01]
-err_V2[2]=[-1.261738538742065e-01, -1.261738538742065e-01]
-err_V2[3]=[-7.522903084754944e-01, -7.522903084754944e-01]
-err_V3[1]=[-2.685473263263702e-01, -2.685473263263702e-01]
-err_V3[2]=[-1.547405272722244e-01, -1.547405272722244e-01]
-err_V3[3]=[3.283977210521698e-01, 3.283977210521698e-01]
-err_V4[1]=[3.375016748905182e-01, 3.375016748905182e-01]
-err_V4[2]=[-1.807919144630432e-01, -1.807919144630432e-01]
-err_V4[3]=[4.122655689716339e-01, 4.122655689716339e-01]
-err_Theta2[1]=[-1.385727864544606e-05, -1.385727864544606e-05]
-err_Theta2[2]=[-7.115472690202296e-04, -7.115472690202296e-04]
-err_Theta2[3]=[-1.253538648597896e-04, -1.253538648597896e-04]
-err_Theta3[1]=[-7.376485737040639e-04, -7.376485737040639e-04]
-err_Theta3[2]=[7.218654500320554e-04, 7.218654500320554e-04]
-err_Theta3[3]=[5.909716710448265e-04, 5.909716710448265e-04]
-err_Theta4[1]=[5.484338034875691e-04, 5.484338034875691e-04]
-err_Theta4[2]=[4.950571455992758e-04, 4.950571455992758e-04]
-err_Theta4[3]=[4.003063804702833e-05, 4.003063804702833e-05]
+err_V2[1]=[-2.23143145442009e-01, -2.23143145442009e-01]
+err_V2[2]=[-1.261598765850067e-01, -1.261598765850067e-01]
+err_V2[3]=[-7.522737979888916e-01, -7.522737979888916e-01]
+err_V3[1]=[-2.689406275749207e-01, -2.689406275749207e-01]
+err_V3[2]=[-1.549007445573807e-01, -1.549007445573807e-01]
+err_V3[3]=[3.28484445810318e-01, 3.28484445810318e-01]
+err_V4[1]=[3.364504873752594e-01, 3.364504873752594e-01]
+err_V4[2]=[-1.808108985424042e-01, -1.808108985424042e-01]
+err_V4[3]=[4.118134379386902e-01, 4.118134379386902e-01]
+err_Theta2[1]=[-1.38554023578763e-05, -1.38554023578763e-05]
+err_Theta2[2]=[-7.115555345080793e-04, -7.115555345080793e-04]
+err_Theta2[3]=[-1.253467635251582e-04, -1.253467635251582e-04]
+err_Theta3[1]=[-7.37674708943814e-04, -7.37674708943814e-04]
+err_Theta3[2]=[7.219464750960469e-04, 7.219464750960469e-04]
+err_Theta3[3]=[5.909476312808692e-04, 5.909476312808692e-04]
+err_Theta4[1]=[5.483925924636424e-04, 5.483925924636424e-04]
+err_Theta4[2]=[4.950347938574851e-04, 4.950347938574851e-04]
+err_Theta4[3]=[3.973107595811598e-05, 3.973107595811598e-05]
diff --git a/...ical_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepUp_YD.txt b/...ical_AC_ThreePhasesUnbalanced_Validation_IEEETests_Test4NodesFeeder_BalancedStepUp_YD.txt
@@ -1,4 +1,4 @@
-last-generated=2020-05-26
+last-generated=2022-04-08
 statistics-initialization=
 {
   "nonlinear": "14",
@@ -11,21 +11,21 @@ statistics-simulation=
   "numerical Jacobians": "0"
 }
 time=[0e+00, 1e+00]
-err_V2[1]=[-6.469275951385498e-01, -6.469275951385498e-01]
-err_V2[2]=[-6.689508557319641e-01, -6.689508557319641e-01]
-err_V2[3]=[-3.268755078315735e-01, -3.268755078315735e-01]
-err_V3[1]=[3.963238000869751e-01, 3.963238000869751e-01]
-err_V3[2]=[-7.651864737272263e-02, -7.651864737272263e-02]
-err_V3[3]=[3.06876540184021e-01, 3.06876540184021e-01]
-err_V4[1]=[4.904395639896393e-01, 4.904395639896393e-01]
-err_V4[2]=[5.137287974357605e-01, 5.137287974357605e-01]
-err_V4[3]=[-2.514242231845856e-01, -2.514242231845856e-01]
-err_Theta2[1]=[-2.907972084358335e-04, -2.907972084358335e-04]
-err_Theta2[2]=[-6.726572755724192e-04, -6.726572755724192e-04]
-err_Theta2[3]=[-4.44967663497664e-05, -4.44967663497664e-05]
-err_Theta3[1]=[-6.424669409170747e-04, -6.424669409170747e-04]
-err_Theta3[2]=[-6.414608797058463e-04, -6.414608797058463e-04]
-err_Theta3[3]=[-6.198485498316586e-04, -6.198485498316586e-04]
-err_Theta4[1]=[-7.087925914674997e-04, -7.087925914674997e-04]
-err_Theta4[2]=[4.774217086378485e-04, 4.774217086378485e-04]
-err_Theta4[3]=[5.070528131909668e-04, 5.070528131909668e-04]
+err_V2[1]=[-6.469129920005798e-01, -6.469129920005798e-01]
+err_V2[2]=[-6.689670085906982e-01, -6.689670085906982e-01]
+err_V2[3]=[-3.268471658229828e-01, -3.268471658229828e-01]
+err_V3[1]=[3.950329124927521e-01, 3.950329124927521e-01]
+err_V3[2]=[-7.661419361829758e-02, -7.661419361829758e-02]
+err_V3[3]=[3.070999085903168e-01, 3.070999085903168e-01]
+err_V4[1]=[4.944804310798645e-01, 4.944804310798645e-01]
+err_V4[2]=[5.193235278129578e-01, 5.193235278129578e-01]
+err_V4[3]=[-2.5112184882164e-01, -2.5112184882164e-01]
+err_Theta2[1]=[-2.907925809267908e-04, -2.907925809267908e-04]
+err_Theta2[2]=[-6.726576248183846e-04, -6.726576248183846e-04]
+err_Theta2[3]=[-4.449787593330257e-05, -4.449787593330257e-05]
+err_Theta3[1]=[-6.424965686164796e-04, -6.424965686164796e-04]
+err_Theta3[2]=[-6.414459203369915e-04, -6.414459203369915e-04]
+err_Theta3[3]=[-6.198995979502797e-04, -6.198995979502797e-04]
+err_Theta4[1]=[-7.086768164299428e-04, -7.086768164299428e-04]
+err_Theta4[2]=[4.773178952746093e-04, 4.773178952746093e-04]
+err_Theta4[3]=[5.070018232800066e-04, 5.070018232800066e-04]
diff --git a/Buildings/package.mo b/Buildings/package.mo
@@ -378,7 +378,27 @@ have been <b style=\"color:blue\">improved</b> in a
                        <a href=\"https://github.com/lbl-srg/modelica-buildings/issues/2835\">issue 2835</a>.
     </td>
 </tr>
-<tr><td colspan=\"2\"><b>Buildings.Fluid.Boilers</b>
+<tr><td colspan=\"2\"><b>Buildings.Electrical.AC.ThreePhasesUnbalanced</b>
+    </td>
+  </tr>
+  <tr><td valign=\"top\">Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.Line<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.Line_N<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.TwoPortMatrixRLC<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.TwoPortMatrixRLC_N<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.TwoPortMatrixRL_N<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.TwoPortRLC<br/>
+                         Buildings.Electrical.AC.ThreePhasesUnbalanced.Lines.TwoPortRLC_N
+    </td>
+    <td valign=\"top\">Set nominal attribute for voltage at terminal.
+                       This change enables Dymola 2023 beta3 to solve
+                       <code>Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepDown.DY</code>
+                       and
+                       <code>Buildings.Electrical.AC.ThreePhasesUnbalanced.Validation.IEEETests.Test4NodesFeeder.UnbalancedStepUp.DD</code>
+                       which otherwise fail during the initialization as the homotopy steps
+                       obtain unreasonable values for the voltages.
+    </td>
+  </tr>
+  <tr><td colspan=\"2\"><b>Buildings.Fluid.Boilers</b>
     </td>
 </tr>
 <tr><td valign=\"top\">Buildings.Fluid.Boilers.Polynomial