diff --git a/dynawaltz-dsl/pom.xml b/dynawaltz-dsl/pom.xml
index 72fcdcf4e..1f9b0f6be 100644
--- a/dynawaltz-dsl/pom.xml
+++ b/dynawaltz-dsl/pom.xml
@@ -51,6 +51,10 @@
             <groupId>com.powsybl</groupId>
             <artifactId>powsybl-dynawaltz</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.apache.groovy</groupId>
+            <artifactId>groovy-json</artifactId>
+        </dependency>
 
         <!-- Test dependencies -->
         <dependency>
diff --git a/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/AbstractEquipmentGroovyExtension.groovy b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/AbstractEquipmentGroovyExtension.groovy
index 770ae5d2c..eff5dc3af 100644
--- a/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/AbstractEquipmentGroovyExtension.groovy
+++ b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/AbstractEquipmentGroovyExtension.groovy
@@ -11,15 +11,12 @@ import com.powsybl.dynawaltz.DynaWaltzProvider
 import com.powsybl.iidm.network.Network
 
 import java.util.function.Consumer
-
 /**
  * @author Laurent Issertial <laurent.issertial at rte-france.com>
  */
 abstract class AbstractEquipmentGroovyExtension<T> {
 
-    protected static final String MODELS_CONFIG = "models.cfg"
-    protected static final String MODEL_PREFIX = "prefix"
-    protected static final String MODEL_PROPERTIES = "properties"
+    protected static final String MODELS_CONFIG = "models.json"
 
     protected final List<EquipmentConfig> equipmentConfigs
 
@@ -28,14 +25,7 @@ abstract class AbstractEquipmentGroovyExtension<T> {
     }
 
     protected AbstractEquipmentGroovyExtension(String modelTag, URL modelConfigUrl) {
-        ConfigSlurper config = new ConfigSlurper()
-        equipmentConfigs = config.parse(modelConfigUrl).get(modelTag).collect {
-            new EquipmentConfig(
-                    it.key as String,
-                    it.value.get(MODEL_PREFIX) as String,
-                    it.value.get(MODEL_PROPERTIES).collect{it.toUpperCase()} as String[]
-            )
-        }
+        equipmentConfigs = ModelsSlurper.instance.getEquipmentConfigs(modelConfigUrl, modelTag)
     }
 
     abstract protected ModelBuilder<T> createBuilder(Network network, EquipmentConfig equipmentConfig);
diff --git a/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/EquipmentConfig.groovy b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/EquipmentConfig.groovy
index b6f22243f..2cf052484 100644
--- a/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/EquipmentConfig.groovy
+++ b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/EquipmentConfig.groovy
@@ -14,7 +14,7 @@ class EquipmentConfig {
     EquipmentConfig(String lib, String prefix, String... properties) {
         this.lib = lib
         this.prefix = prefix
-        this.properties = properties
+        this.properties = properties ? properties.collect{it.toUpperCase()} as List<String> : [] as List<String>
     }
 
     boolean isControllable() {
diff --git a/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/ModelsSlurper.groovy b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/ModelsSlurper.groovy
new file mode 100644
index 000000000..e66ae2e2a
--- /dev/null
+++ b/dynawaltz-dsl/src/main/groovy/com/powsybl/dynawaltz/dsl/ModelsSlurper.groovy
@@ -0,0 +1,34 @@
+/**
+ * Copyright (c) 2023, RTE (http://www.rte-france.com/)
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ * SPDX-License-Identifier: MPL-2.0
+ */
+package com.powsybl.dynawaltz.dsl
+
+import groovy.json.JsonSlurper
+import org.apache.groovy.json.internal.LazyMap
+
+/**
+ * @author Laurent Issertial <laurent.issertial at rte-france.com>
+ */
+@Singleton
+class ModelsSlurper {
+
+    private static final String MODEL_LIB = "lib"
+    private static final String MODEL_PREFIX = "prefix"
+    private static final String MODEL_PROPERTIES = "properties"
+
+    private final slurper = new JsonSlurper()
+    private final Map<URL, LazyMap> libsList = new HashMap<>()
+
+    def getEquipmentConfigs(URL url, String modelTag) {
+        libsList.computeIfAbsent(url, u -> slurper.parse(u))[modelTag].collect() {
+            new EquipmentConfig(
+                    it[MODEL_LIB] as String,
+                    it[MODEL_PREFIX] as String,
+                    it[MODEL_PROPERTIES] as String[])
+        }
+    }
+}
diff --git a/dynawaltz-dsl/src/main/resources/models.cfg b/dynawaltz-dsl/src/main/resources/models.cfg
deleted file mode 100644
index a04d38a7a..000000000
--- a/dynawaltz-dsl/src/main/resources/models.cfg
+++ /dev/null
@@ -1,107 +0,0 @@
-synchronousGenerators {
-     GeneratorSynchronousFourWindings
-     GeneratorSynchronousFourWindingsGoverPropVRPropInt.properties = ["Controllable"]
-     GeneratorSynchronousFourWindingsGovSteam1ExcIEEEST4B
-     GeneratorSynchronousFourWindingsGovSteam1ExcIEEEST4BPssIEEE2B
-     GeneratorSynchronousFourWindingsPmConstVRNordic
-     GeneratorSynchronousFourWindingsPmConstVRNordicTfo
-     GeneratorSynchronousFourWindingsProportionalRegulations.properties = ["Controllable"]
-     GeneratorSynchronousFourWindingsTGov1Sexs
-     GeneratorSynchronousFourWindingsTGov1SexsPss2A
-     GeneratorSynchronousFourWindingsVRKundur
-     GeneratorSynchronousFourWindingsVRKundurPssKundur
-     GeneratorSynchronousProportionalRegulationsInternalParameters
-     GeneratorSynchronousThreeWindings
-     GeneratorSynchronousThreeWindingsGoverNordicVRNordic
-     GeneratorSynchronousThreeWindingsGoverNordicVRNordicTfo
-     GeneratorSynchronousThreeWindingsGoverPropVRPropInt.properties = ["Controllable"]
-     GeneratorSynchronousThreeWindingsPmConstVRNordic
-     GeneratorSynchronousThreeWindingsPmConstVRNordicTfo
-     GeneratorSynchronousThreeWindingsProportionalRegulations.properties = ["Controllable"]
-}
-
-synchronizedGenerators {
-    GeneratorPQ
-    GeneratorPV.properties = ["Controllable"]
-    GeneratorPVFixed
-    GeneratorPVDiagramPQ
-}
-
-hvdcPv {
-    HvdcPV
-    HvdcPVEmulation
-    HvdcPVEmulationSet
-    HvdcPVDiagramPQ
-    HvdcPVDiagramPQEmulation
-    HvdcPVDiagramPQEmulationSet
-    HvdcPTanPhi
-    HvdcPTanPhiDiagramPQ
-    HvdcPVDangling.properties = ["Dangling"]
-    HvdcPVDanglingDiagramPQ.properties = ["Dangling"]
-    HvdcPTanPhiDangling.properties = ["Dangling"]
-    HvdcPTanPhiDanglingDiagramPQ.properties = ["Dangling"]
-}
-
-hvdcVsc {
-    HvdcVSC
-    HvdcVSCEmulation
-    HvdcVSCDanglingP.properties = ["Dangling"]
-    HvdcVSCDanglingUdc.properties = ["Dangling"]
-}
-
-infiniteBuses {
-    InfiniteBus
-    InfiniteBusWithImpedance
-    InfiniteBusWithVariations
-}
-
-baseLoads {
-    LoadAlphaBeta.properties = ["Controllable"]
-    LoadAlphaBetaRestorative
-    LoadAlphaBetaRestorativeLimitsRecalc
-    LoadAlphaBetaMotor
-    LoadPQ
-}
-
-staticVarCompensators {
-    StaticVarCompensator
-    StaticVarCompensatorPV
-    StaticVarCompensatorPVModeHandling
-    StaticVarCompensatorPVRemote
-    StaticVarCompensatorPVRemoteModeHandling
-    StaticVarCompensatorPVProp
-    StaticVarCompensatorPVPropModeHandling
-    StaticVarCompensatorPVPropRemote
-    StaticVarCompensatorPVPropRemoteModeHandling
-}
-
-transformers {
-    TransformerFixedRatio
-}
-
-wecc {
-   WTG4AWeccCurrentSource {
-        prefix = "WTG4A"
-        properties = ["Synchronized"]
-   }
-   WTG4BWeccCurrentSource {
-        prefix = "WTG4B"
-        properties = ["Synchronized"]
-   }
-   WT4AWeccCurrentSource.prefix = "WT4A"
-   WT4BWeccCurrentSource.prefix = "WT4B"
-   PhotovoltaicsWeccCurrentSource {
-        prefix = "WTG4A"
-        properties = ["Synchronized"]
-   }
-   PhotovoltaicsWeccVoltageSource {
-        prefix = "photovoltaics"
-        properties = ["Synchronized"]
-   }
-}
-
-gridFormingConverter {
-    GridFormingConverterDroopControl.properties = ["Synchronized"]
-    GridFormingConverterMatchingControl.properties = ["Synchronized"]
-    GridFormingConverterDispatchableVirtualOscillatorControl.properties = ["Synchronized"]
-}
diff --git a/dynawaltz-dsl/src/main/resources/models.json b/dynawaltz-dsl/src/main/resources/models.json
new file mode 100644
index 000000000..509b42c9a
--- /dev/null
+++ b/dynawaltz-dsl/src/main/resources/models.json
@@ -0,0 +1,283 @@
+{
+  "synchronousGenerators": [
+    {
+      "lib": "GeneratorSynchronousFourWindings"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsGoverPropVRPropInt",
+      "properties": [
+        "Controllable"
+      ]
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsGovSteam1ExcIEEEST4B"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsGovSteam1ExcIEEEST4BPssIEEE2B"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsPmConstVRNordic"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsPmConstVRNordicTfo"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsProportionalRegulations",
+      "properties": [
+        "Controllable"
+      ]
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsTGov1Sexs"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsTGov1SexsPss2A"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsVRKundur"
+    },
+    {
+      "lib": "GeneratorSynchronousFourWindingsVRKundurPssKundur"
+    },
+    {
+      "lib": "GeneratorSynchronousProportionalRegulationsInternalParameters"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindings"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsGoverNordicVRNordic"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsGoverNordicVRNordicTfo"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsGoverPropVRPropInt",
+      "properties": [
+        "Controllable"
+      ]
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsPmConstVRNordic"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsPmConstVRNordicTfo"
+    },
+    {
+      "lib": "GeneratorSynchronousThreeWindingsProportionalRegulations",
+      "properties": [
+        "Controllable"
+      ]
+    }
+  ],
+  "synchronizedGenerators": [
+    {
+      "lib": "GeneratorPQ"
+    },
+    {
+      "lib": "GeneratorPV",
+      "properties": [
+        "Controllable"
+      ]
+    },
+    {
+      "lib": "GeneratorPVFixed"
+    },
+    {
+      "lib": "GeneratorPVDiagramPQ"
+    }
+  ],
+  "hvdcPv": [
+    {
+      "lib": "HvdcPV"
+    },
+    {
+      "lib": "HvdcPVEmulation"
+    },
+    {
+      "lib": "HvdcPVEmulationSet"
+    },
+    {
+      "lib": "HvdcPVDiagramPQ"
+    },
+    {
+      "lib": "HvdcPVDiagramPQEmulation"
+    },
+    {
+      "lib": "HvdcPVDiagramPQEmulationSet"
+    },
+    {
+      "lib": "HvdcPTanPhi"
+    },
+    {
+      "lib": "HvdcPTanPhiDiagramPQ"
+    },
+    {
+      "lib": "HvdcPVDangling",
+      "properties": [
+        "Dangling"
+      ]
+    },
+    {
+      "lib": "HvdcPVDanglingDiagramPQ",
+      "properties": [
+        "Dangling"
+      ]
+    },
+    {
+      "lib": "HvdcPTanPhiDangling",
+      "properties": [
+        "Dangling"
+      ]
+    },
+    {
+      "lib": "HvdcPTanPhiDanglingDiagramPQ",
+      "properties": [
+        "Dangling"
+      ]
+    }
+  ],
+  "hvdcVsc": [
+    {
+      "lib": "HvdcVSC"
+    },
+    {
+      "lib": "HvdcVSCEmulation"
+    },
+    {
+      "lib": "HvdcVSCDanglingP",
+      "properties": [
+        "Dangling"
+      ]
+    },
+    {
+      "lib": "HvdcVSCDanglingUdc",
+      "properties": [
+        "Dangling"
+      ]
+    }
+  ],
+  "infiniteBuses": [
+    {
+      "lib": "InfiniteBus"
+    },
+    {
+      "lib": "InfiniteBusWithImpedance"
+    },
+    {
+      "lib": "InfiniteBusWithVariations"
+    }
+  ],
+  "baseLoads": [
+    {
+      "lib": "LoadAlphaBeta",
+      "properties": [
+        "Controllable"
+      ]
+    },
+    {
+      "lib": "LoadAlphaBetaRestorative"
+    },
+    {
+      "lib": "LoadAlphaBetaRestorativeLimitsRecalc"
+    },
+    {
+      "lib": "LoadAlphaBetaMotor"
+    },
+    {
+      "lib": "LoadPQ"
+    }
+  ],
+  "staticVarCompensators": [
+    {
+      "lib": "StaticVarCompensator"
+    },
+    {
+      "lib": "StaticVarCompensatorPV"
+    },
+    {
+      "lib": "StaticVarCompensatorPVModeHandling"
+    },
+    {
+      "lib": "StaticVarCompensatorPVRemote"
+    },
+    {
+      "lib": "StaticVarCompensatorPVRemoteModeHandling"
+    },
+    {
+      "lib": "StaticVarCompensatorPVProp"
+    },
+    {
+      "lib": "StaticVarCompensatorPVPropModeHandling"
+    },
+    {
+      "lib": "StaticVarCompensatorPVPropRemote"
+    },
+    {
+      "lib": "StaticVarCompensatorPVPropRemoteModeHandling"
+    }
+  ],
+  "transformers": [
+    {
+      "lib": "TransformerFixedRatio"
+    }
+  ],
+  "wecc": [
+    {
+      "lib": "WTG4AWeccCurrentSource",
+      "prefix": "WTG4A",
+      "properties": [
+        "Synchronized"
+      ]
+    },
+    {
+      "lib": "WTG4BWeccCurrentSource",
+      "prefix": "WTG4B",
+      "properties": [
+        "Synchronized"
+      ]
+    },
+    {
+      "lib": "WT4AWeccCurrentSource",
+      "prefix": "WT4A"
+    },
+    {
+      "lib": "WT4BWeccCurrentSource",
+      "prefix": "WT4B"
+    },
+    {
+      "lib": "PhotovoltaicsWeccCurrentSource",
+      "prefix": "WTG4A",
+      "properties": [
+        "Synchronized"
+      ]
+    },
+    {
+      "lib": "PhotovoltaicsWeccVoltageSource",
+      "prefix": "photovoltaics",
+      "properties": [
+        "Synchronized"
+      ]
+    }
+  ],
+  "gridFormingConverter": [
+    {
+      "lib": "GridFormingConverterDroopControl",
+      "properties": [
+        "Synchronized"
+      ]
+    },
+    {
+      "lib": "GridFormingConverterMatchingControl",
+      "properties": [
+        "Synchronized"
+      ]
+    },
+    {
+      "lib": "GridFormingConverterDispatchableVirtualOscillatorControl",
+      "properties": [
+        "Synchronized"
+      ]
+    }
+  ]
+}
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index 4bdf0ab51..745b91a89 100644
--- a/pom.xml
+++ b/pom.xml
@@ -56,11 +56,8 @@
 
     <properties>
         <java.version>17</java.version>
-
-        <groovy.version>3.0.9</groovy.version> <!-- used for groovydoc (dynawaltz-dsl) -->
-
         <powsyblcore.version>6.0.0-RC1</powsyblcore.version>
-
+        <groovy.version>4.0.14</groovy.version> <!-- used for groovy-json but also for groovydoc (dynawaltz-dsl) -->
         <sonar.coverage.jacoco.xmlReportPaths>
             ../distribution/target/site/jacoco-aggregate/jacoco.xml,
         </sonar.coverage.jacoco.xmlReportPaths>
@@ -144,6 +141,12 @@
                 <artifactId>powsybl-dynawo-integration-tests</artifactId>
                 <version>${project.version}</version>
             </dependency>
+
+            <dependency>
+                <groupId>org.apache.groovy</groupId>
+                <artifactId>groovy-json</artifactId>
+                <version>${groovy.version}</version>
+            </dependency>
         </dependencies>
     </dependencyManagement>