diff --git a/src/main/java/com/powsybl/openloadflow/sensi/AbstractSensitivityAnalysis.java b/src/main/java/com/powsybl/openloadflow/sensi/AbstractSensitivityAnalysis.java
index 9fddff513c..49deb80ba3 100644
--- a/src/main/java/com/powsybl/openloadflow/sensi/AbstractSensitivityAnalysis.java
+++ b/src/main/java/com/powsybl/openloadflow/sensi/AbstractSensitivityAnalysis.java
@@ -772,7 +772,8 @@ public SensitivityFactorHolder readAndCheckFactors(Network network, Map<String,
                         checkRegulatingTerminal(network, variableId);
                         Terminal regulatingTerminal = getEquipmentRegulatingTerminal(network, variableId);
                         assert regulatingTerminal != null; // this cannot fail because it is checked in checkRegulatingTerminal
-                        variableElement = lfNetwork.getBusById(regulatingTerminal.getBusView().getBus().getId());
+                        Bus regulatedBus = regulatingTerminal.getBusView().getBus();
+                        variableElement = regulatedBus != null ? lfNetwork.getBusById(regulatedBus.getId()) : null;
                     } else {
                         throw new PowsyblException("Variable type " + variableType + " not supported with function type " + functionType);
                     }
diff --git a/src/test/java/com/powsybl/openloadflow/sensi/ac/AcSensitivityAnalysisTest.java b/src/test/java/com/powsybl/openloadflow/sensi/ac/AcSensitivityAnalysisTest.java
index 67d3ebbb06..f66ab8049a 100644
--- a/src/test/java/com/powsybl/openloadflow/sensi/ac/AcSensitivityAnalysisTest.java
+++ b/src/test/java/com/powsybl/openloadflow/sensi/ac/AcSensitivityAnalysisTest.java
@@ -542,6 +542,23 @@ void testBusVoltageOnAbsentBus() {
         assertEquals("The bus ref for 'id' cannot be resolved.", e.getCause().getMessage());
     }
 
+    @Test
+    void disconnectedGeneratorShouldBeSkipped() {
+        Network network = FourBusNetworkFactory.create();
+        SensitivityAnalysisParameters sensiParameters = createParameters(false, "b1_vl_0", true);
+        sensiParameters.getLoadFlowParameters().setBalanceType(LoadFlowParameters.BalanceType.PROPORTIONAL_TO_GENERATION_P_MAX);
+        //Disconnect g4 generator
+        network.getGenerator("g4").getTerminal().disconnect();
+
+        TargetVoltage targetVoltage = new TargetVoltage("g4", "g4", "g4");
+        BusVoltage busVoltage = new BusVoltage("b1", "b1", new IdBasedBusRef("b1"));
+        SensitivityFactorsProvider factorsProvider = n -> Collections.singletonList(new BusVoltagePerTargetV(busVoltage, targetVoltage));
+        SensitivityAnalysisResult result = sensiProvider.run(network, VariantManagerConstants.INITIAL_VARIANT_ID, factorsProvider, Collections.emptyList(),
+            sensiParameters, LocalComputationManager.getDefault())
+            .join();
+        assertTrue(result.getSensitivityValues().isEmpty());
+    }
+
     @Test
     void testBranchFunctionOutsideMainComponent() {
         testBranchFunctionOutsideMainComponent(false);