diff --git a/PowerSystems/Control/Modulation.mo b/PowerSystems/Control/Modulation.mo
index d922905..0c060b0 100644
--- a/PowerSystems/Control/Modulation.mo
+++ b/PowerSystems/Control/Modulation.mo
@@ -1238,7 +1238,7 @@ package SpaceVector "Space vector logic and control"
             origin={-240,-70},
             extent={{-10,-10},{10,10}},
             rotation=270)));
-    Modelica.StateGraph.StepWithSignal sector2
+    Modelica.StateGraph.StepWithSignal sector2(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,170},{138,190}})));
     Modelica.StateGraph.TransitionWithSignal t1
     annotation (Placement(transformation(extent={{-124,190},{-104,210}})));
@@ -1260,10 +1260,10 @@ package SpaceVector "Space vector logic and control"
     annotation (Placement(transformation(extent={{-124,30},{-104,50}})));
     Modelica.StateGraph.Alternative Alternative2
     annotation (Placement(transformation(extent={{-58,124},{218,276}})));
-    Modelica.StateGraph.Step Step1
+    Modelica.StateGraph.Step Step1(nIn = 1, nOut = 1)
                                  annotation (Placement(transformation(extent={{
                 -94,190},{-74,210}})));
-    Modelica.StateGraph.Step Step2
+    Modelica.StateGraph.Step Step2(nIn = 1, nOut = 1)
                                  annotation (Placement(transformation(extent={{
                 -94,30},{-74,50}})));
     Modelica.StateGraph.Alternative Alternative3
@@ -1276,10 +1276,10 @@ package SpaceVector "Space vector logic and control"
     annotation (Placement(transformation(extent={{-4,228},{16,248}})));
     Modelica.StateGraph.TransitionWithSignal t4
     annotation (Placement(transformation(extent={{-2,152},{18,172}})));
-    Modelica.StateGraph.Step Step3
+    Modelica.StateGraph.Step Step3(nIn = 1, nOut = 1)
                                  annotation (Placement(transformation(extent={{
                 28,152},{48,172}})));
-    Modelica.StateGraph.Step Step4
+    Modelica.StateGraph.Step Step4(nIn = 1, nOut = 1)
                                  annotation (Placement(transformation(extent={{
                 26,68},{46,88}})));
     Modelica.StateGraph.TransitionWithSignal t5
@@ -1300,15 +1300,15 @@ package SpaceVector "Space vector logic and control"
     annotation (Placement(transformation(extent={{88,86},{108,106}})));
     Modelica.StateGraph.TransitionWithSignal t10
     annotation (Placement(transformation(extent={{88,50},{108,70}})));
-    Modelica.StateGraph.StepWithSignal sector3
+    Modelica.StateGraph.StepWithSignal sector3(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,134},{138,154}})));
-    Modelica.StateGraph.StepWithSignal sector1
+    Modelica.StateGraph.StepWithSignal sector1(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,228},{138,248}})));
-    Modelica.StateGraph.StepWithSignal sector6
+    Modelica.StateGraph.StepWithSignal sector6(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,-8},{138,12}})));
-    Modelica.StateGraph.StepWithSignal sector5
+    Modelica.StateGraph.StepWithSignal sector5(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,50},{138,70}})));
-    Modelica.StateGraph.StepWithSignal sector4
+    Modelica.StateGraph.StepWithSignal sector4(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{118,86},{138,106}})));
     Modelica.StateGraph.Transition t11(enableTimer=true, waitTime=T_pwm)
     annotation (Placement(transformation(extent={{148,228},{168,248}})));
@@ -1353,7 +1353,7 @@ package SpaceVector "Space vector logic and control"
   annotation (Placement(transformation(extent={{-280,-160},{-260,-140}})));
     Modelica.Blocks.Interfaces.BooleanOutput trigger
     annotation (Placement(transformation(extent={{300,100},{340,140}})));
-    Modelica.StateGraph.InitialStep InitialStep1
+    Modelica.StateGraph.InitialStep InitialStep1(nIn = 1, nOut = 1)
     annotation (Placement(transformation(extent={{-280,110},{-260,130}})));
     Modelica.Blocks.Logical.Or Or1
                                  annotation (Placement(transformation(extent={{
diff --git a/PowerSystems/Examples/AC3ph/Drives.mo b/PowerSystems/Examples/AC3ph/Drives.mo
index 62dbd1d..e96f145 100644
--- a/PowerSystems/Examples/AC3ph/Drives.mo
+++ b/PowerSystems/Examples/AC3ph/Drives.mo
@@ -260,7 +260,7 @@ Compare 'transient' and 'steady-state' mode.</p>
       controllerType=Modelica.Blocks.Types.SimpleController.PI,
       Ti=0.1,
       yMax=1,
-      initType=Modelica.Blocks.Types.InitPID.SteadyState,
+      initType=Modelica.Blocks.Types.Init.SteadyState,
       gainPID(y(start=0.1)))
            annotation (Placement(transformation(extent={{-50,0},{-30,20}})));
 
@@ -427,7 +427,7 @@ The machine defines the reference-system independent of the system choice (as ne
       Ti=0.2,
       Td=0.1,
       controllerType=Modelica.Blocks.Types.SimpleController.PI,
-      initType=Modelica.Blocks.Types.InitPID.SteadyState,
+      initType=Modelica.Blocks.Types.Init.SteadyState,
       yMax=1,
       gainPID(y(start=0.1)))
            annotation (Placement(transformation(extent={{-60,10},{-40,30}})));
@@ -513,7 +513,7 @@ On-load steady-state start with torque-increase at 3 s and load-step 6 s.</p>
       Td=0.05,
       controllerType=Modelica.Blocks.Types.SimpleController.PI,
       Ti=0.2,
-      initType=Modelica.Blocks.Types.InitPID.InitialState,
+      initType=Modelica.Blocks.Types.Init.InitialState,
       xi_start=0.1,
       yMax=1)
            annotation (Placement(transformation(extent={{-60,10},{-40,30}})));
@@ -614,7 +614,7 @@ Transient start with torque-increase at 0.5 s and load-step 2 s.</p>
       Ti=0.1,
       yMax=1,
       gainPID(y(start=0.1)),
-      initType=Modelica.Blocks.Types.InitPID.SteadyState)
+      initType=Modelica.Blocks.Types.Init.SteadyState)
            annotation (Placement(transformation(extent={{-60,10},{-40,30}})));
 
   equation
diff --git a/PowerSystems/Examples/AC3ph/Generation.mo b/PowerSystems/Examples/AC3ph/Generation.mo
index 8dbb29f..723be0e 100644
--- a/PowerSystems/Examples/AC3ph/Generation.mo
+++ b/PowerSystems/Examples/AC3ph/Generation.mo
@@ -1175,7 +1175,7 @@ annotation (Placement(transformation(extent={{-100,80},{-80,100}})));
     Td=0.1,
     Ti=0.5,
     k=1/vDC_nom,
-    initType=Modelica.Blocks.Types.InitPID.SteadyState)
+    initType=Modelica.Blocks.Types.Init.SteadyState)
          annotation (Placement(transformation(extent={{40,20},{20,40}})));
   Modelica.Blocks.Sources.Constant set_vDC(k=vDC_nom)
       annotation (Placement(transformation(extent={{70,20},{50,40}})));
@@ -1302,7 +1302,7 @@ annotation (Placement(transformation(extent={{-100,80},{-80,100}})));
   Modelica.Blocks.Continuous.LimPID PI_vDC(
       Td=0.05,
       controllerType=Modelica.Blocks.Types.SimpleController.PI,
-      initType=Modelica.Blocks.Types.InitPID.SteadyState,
+      initType=Modelica.Blocks.Types.Init.SteadyState,
     Ti=0.1,
       k=0.3*I_nom/vDC_nom,
       yMax=1.4*I_nom)
diff --git a/PowerSystems/Types/SI.mo b/PowerSystems/Types/SI.mo
index 0445b39..fefcf68 100644
--- a/PowerSystems/Types/SI.mo
+++ b/PowerSystems/Types/SI.mo
@@ -1,7 +1,7 @@
 within PowerSystems.Types;
 package SI "SI types with custom attributes, like display units"
   extends Modelica.Icons.Package;
-  import MSI = Modelica.SIunits;
+  import MSI = Modelica.Units.SI;
 
   type Time = MSI.Time;
   type Frequency = MSI.Frequency;
diff --git a/PowerSystems/package.mo b/PowerSystems/package.mo
index 7c5101f..8ceda05 100644
--- a/PowerSystems/package.mo
+++ b/PowerSystems/package.mo
@@ -32,7 +32,7 @@ by funding of the IST Programme, Contract No. IST-1999-11979. </i></p>
 <p/>
 </html>
 "),
-  uses(Modelica(version="3.2.3")),
+  uses(Modelica(version="4.0.0")),
   Icon(graphics={
       Line(
         points={{-60,-16},{38,-16}},