ORNL · lukelowry · May 28, 2026
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -62,6 +62,7 @@
 - Added cmake-format hooks, including in pre-commit.
 - Added off-nominal tap ratio and phase shift support to the PhasorDynamics `Branch` model.
 - Added `REGCA` converter model implementation for PhasorDynamics.
+- Added `REPCA` converter model implementation for PhasorDynamics.
 
 ## v0.1
 

diff --git a/GridKit/Model/PhasorDynamics/ComponentLibrary.hpp b/GridKit/Model/PhasorDynamics/ComponentLibrary.hpp
@@ -5,6 +5,7 @@
 #include <GridKit/Model/PhasorDynamics/BusFault/BusFault.hpp>
 #include <GridKit/Model/PhasorDynamics/BusToSignalAdapter/BusToSignalAdapter.hpp>
 #include <GridKit/Model/PhasorDynamics/Converter/REGCA/Regca.hpp>
+#include <GridKit/Model/PhasorDynamics/Converter/REPCA/Repca.hpp>
 #include <GridKit/Model/PhasorDynamics/Exciter/IEEET1/Ieeet1.hpp>
 #include <GridKit/Model/PhasorDynamics/Exciter/SEXS-PTI/SexsPti.hpp>
 #include <GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1.hpp>

diff --git a/GridKit/Model/PhasorDynamics/Converter/CMakeLists.txt b/GridKit/Model/PhasorDynamics/Converter/CMakeLists.txt
@@ -4,3 +4,4 @@
 # ]]
 
 add_subdirectory(REGCA)
+add_subdirectory(REPCA)
diff --git a/GridKit/Model/PhasorDynamics/Converter/README.md b/GridKit/Model/PhasorDynamics/Converter/README.md
@@ -12,3 +12,4 @@ The GridKit converter documentation includes:
 - Renewable Energy Generator/Converter Model REGCA (See [REGCA](REGCA/README.md))
 - Renewable Energy Generator/Converter Model REGCB (See [REGCB](REGCB/README.md))
 - Renewable Energy Electrical Control Model REECA (See [REECA](REECA/README.md))
+- Renewable Energy Plant Control Model REPCA (See [REPCA](REPCA/README.md))
diff --git a/GridKit/Model/PhasorDynamics/Converter/REPCA/CMakeLists.txt b/GridKit/Model/PhasorDynamics/Converter/REPCA/CMakeLists.txt
@@ -0,0 +1,54 @@
+# [[
+#  Author(s):
+#    - Luke Lowery <lukel@tamu.edu>
+# ]]
+
+set(_install_headers Repca.hpp RepcaData.hpp)
+
+if(GRIDKIT_ENABLE_ENZYME)
+  gridkit_add_library(
+    phasor_dynamics_converter_repca
+    SOURCES RepcaEnzyme.cpp
+    HEADERS ${_install_headers}
+    INCLUDE_DIRECTORIES PRIVATE ${GRIDKIT_THIRD_PARTY_DIR}/magic-enum/include
+    LINK_LIBRARIES
+      PUBLIC
+      GridKit::phasor_dynamics_core
+      PUBLIC
+      GridKit::phasor_dynamics_signal
+      PRIVATE
+      ClangEnzymeFlags
+    COMPILE_OPTIONS
+      PRIVATE
+      -mllvm
+      -enzyme-auto-sparsity=1
+      -fno-math-errno)
+else()
+  gridkit_add_library(
+    phasor_dynamics_converter_repca
+    SOURCES Repca.cpp
+    HEADERS ${_install_headers}
+    INCLUDE_DIRECTORIES PRIVATE ${GRIDKIT_THIRD_PARTY_DIR}/magic-enum/include
+    LINK_LIBRARIES
+      PUBLIC
+      GridKit::phasor_dynamics_core
+      PUBLIC
+      GridKit::phasor_dynamics_signal)
+endif()
+
+gridkit_add_library(
+  phasor_dynamics_converter_repca_dependency_tracking
+  SOURCES RepcaDependencyTracking.cpp
+  INCLUDE_DIRECTORIES PRIVATE ${GRIDKIT_THIRD_PARTY_DIR}/magic-enum/include
+  LINK_LIBRARIES
+    PUBLIC
+    GridKit::phasor_dynamics_core
+    PUBLIC
+    GridKit::phasor_dynamics_signal_dependency_tracking)
+
+target_link_libraries(
+  phasor_dynamics_components
+  INTERFACE GridKit::phasor_dynamics_converter_repca)
+target_link_libraries(
+  phasor_dynamics_components_dependency_tracking
+  INTERFACE GridKit::phasor_dynamics_converter_repca_dependency_tracking)
diff --git a/GridKit/Model/PhasorDynamics/Converter/REPCA/README.md b/GridKit/Model/PhasorDynamics/Converter/REPCA/README.md
diff --git a/GridKit/Model/PhasorDynamics/Converter/REPCA/Repca.cpp b/GridKit/Model/PhasorDynamics/Converter/REPCA/Repca.cpp
@@ -0,0 +1,27 @@
+/**
+ * @file Repca.cpp
+ * @author Luke Lowery (lukel@tamu.edu)
+ * @brief Non-Enzyme instantiation for the REPCA plant-control model.
+ */
+
+#include "RepcaImpl.hpp"
+
+namespace GridKit
+{
+  namespace PhasorDynamics
+  {
+    namespace Converter
+    {
+      template <class ScalarT, typename IdxT>
+      int Repca<ScalarT, IdxT>::evaluateJacobian()
+      {
+        Log::misc() << "Evaluate Jacobian for Repca..." << std::endl;
+        Log::misc() << "Jacobian evaluation is not implemented!" << std::endl;
+        return 0;
+      }
+
+      template class Repca<double, long int>;
+      template class Repca<double, size_t>;
+    } // namespace Converter
+  } // namespace PhasorDynamics
+} // namespace GridKit
diff --git a/GridKit/Model/PhasorDynamics/Converter/REPCA/Repca.hpp b/GridKit/Model/PhasorDynamics/Converter/REPCA/Repca.hpp
@@ -0,0 +1,190 @@
+/**
+ * @file Repca.hpp
+ * @author Luke Lowery (lukel@tamu.edu)
+ * @brief Declaration of the REPCA plant-control model.
+ */
+
+#pragma once
+
+#include <cstddef>
+#include <memory>
+#include <vector>
+
+#include <GridKit/Model/PhasorDynamics/Component.hpp>
+#include <GridKit/Model/PhasorDynamics/ComponentSignals.hpp>
+#include <GridKit/Model/PhasorDynamics/Converter/REPCA/RepcaData.hpp>
+#include <GridKit/Model/VariableMonitor.hpp>
+
+namespace GridKit
+{
+  namespace PhasorDynamics
+  {
+    template <class ScalarT, typename IdxT>
+    class BusBase;
+
+    template <class ScalarT, typename IdxT>
+    class SignalNode;
+
+    namespace Converter
+    {
+      /// Internal variables of a `Repca`.
+      enum class RepcaInternalVariables : size_t
+      {
+        VMEAS,  ///< Filtered regulated voltage
+        QMEAS,  ///< Filtered reactive-power signal
+        XQ,     ///< Reactive PI state
+        XQEXT,  ///< Reactive-command lead-lag state
+        PMEAS,  ///< Filtered active-power signal
+        XP,     ///< Active-power PI state
+        PREF,   ///< Active-power command lag state
+        VREG,   ///< Regulated-bus voltage magnitude
+        VLDC,   ///< Line-drop compensated voltage magnitude
+        VDROOP, ///< Reactive-droop-compensated voltage
+        VCTRL,  ///< Selected voltage-measurement input
+        SFRZ,   ///< Reactive PI voltage-enable indicator
+        ERQ,    ///< Selected reactive-loop error
+        ERQDB,  ///< Deadbanded reactive-loop error
+        ERQLIM, ///< Limited reactive-loop error
+        QPI,    ///< Reactive PI output
+        QEXT,   ///< Reactive-power command output
+        EF,     ///< Frequency error after deadband
+        EP,     ///< Active-power control error
+        EPLIM,  ///< Limited active-power control error
+        PPI,    ///< Active-power PI output
+        PEXT,   ///< Active-power command output
+        MAXIMUM,
+      };
+
+      /// External variables of a `Repca`.
+      enum class RepcaExternalVariables : size_t
+      {
+        IBRANCHR,  ///< Branch current real component on component base
+        IBRANCHI,  ///< Branch current imaginary component on component base
+        QBRANCH,   ///< Branch reactive-power signal on system base
+        PBRANCH,   ///< Branch active-power signal on system base
+        VREF,      ///< Voltage reference
+        QREF,      ///< Reactive-power reference
+        PPLANTREF, ///< Plant active-power reference
+        FREQ,      ///< Optional frequency input
+        FREQREF,   ///< Optional frequency reference
+        MAXIMUM,
+      };
+
+      template <class ScalarT, typename IdxT>
+      class Repca : public Component<ScalarT, IdxT>
+      {
+        using Component<ScalarT, IdxT>::alpha_;
+        using Component<ScalarT, IdxT>::f_;
+        using Component<ScalarT, IdxT>::gridkit_component_id_;
+        using Component<ScalarT, IdxT>::J_;
+        using Component<ScalarT, IdxT>::J_cols_buffer_;
+        using Component<ScalarT, IdxT>::J_rows_buffer_;
+        using Component<ScalarT, IdxT>::J_vals_buffer_;
+        using Component<ScalarT, IdxT>::residual_indices_;
+        using Component<ScalarT, IdxT>::size_;
+        using Component<ScalarT, IdxT>::tag_;
+        using Component<ScalarT, IdxT>::va_system_base_;
+        using Component<ScalarT, IdxT>::variable_indices_;
+        using Component<ScalarT, IdxT>::wb_;
+        using Component<ScalarT, IdxT>::y_;
+        using Component<ScalarT, IdxT>::yp_;
+
+      public:
+        using RealT           = typename Component<ScalarT, IdxT>::RealT;
+        using bus_type        = BusBase<ScalarT, IdxT>;
+        using signal_type     = SignalNode<ScalarT, IdxT>;
+        using model_data_type = RepcaData<RealT, IdxT>;
+        using MonitorT        = Model::VariableMonitor<Repca, RepcaData>;
+
+        Repca(bus_type* bus);
+        Repca(bus_type* bus, const model_data_type& data);
+        ~Repca();
+
+        int setGridKitComponentID(IdxT) override final;
+        int allocate() override final;
+        int verify() const override final;
+        int initialize() override final;
+        int tagDifferentiable() override final;
+        int evaluateResidual() override final;
+        int evaluateJacobian() override final;
+
+        auto getSignals()
+            -> ComponentSignals<ScalarT,
+                                IdxT,
+                                RepcaInternalVariables,
+                                RepcaExternalVariables>&
+        {
+          return signals_;
+        }
+
+        const Model::VariableMonitorBase* getMonitor() const override;
+
+        __attribute__((always_inline)) inline int evaluateInternalResidual(
+            ScalarT*, ScalarT*, ScalarT*, ScalarT*, ScalarT*);
+
+      private:
+        void initModelParams(const model_data_type& data);
+        void initializeMonitor();
+
+        int     verifyBranchSignalPorts() const;
+        ScalarT readExternalOrDefault(RepcaExternalVariables variable, ScalarT default_value) const;
+        void    setDerivedParameters();
+        ScalarT toComponentBase(ScalarT value) const;
+
+        ScalarT& Vr();
+        ScalarT& Vi();
+
+        bus_type* bus_{nullptr};
+
+        RealT mva_base_{0};
+        RealT VcompFlag_{0};
+        RealT RefFlag_{0};
+        RealT Freqflag_{0};
+        RealT Tfltr_{0};
+        RealT Tft_{0};
+        RealT Tfv_{0};
+        RealT Tp_{0};
+        RealT Tlag_{0};
+        RealT Vfrz_{0};
+        RealT Rc_{0};
+        RealT Xc_{0};
+        RealT Kc_{0};
+        RealT dbdlow_{0};
+        RealT dbdupper_{0};
+        RealT emax_{0};
+        RealT emin_{0};
+        RealT Kp_{0};
+        RealT Ki_{0};
+        RealT Qmax_{0};
+        RealT Qmin_{0};
+        RealT fdbd1_{0};
+        RealT fdbd2_{0};
+        RealT Ddn_{0};
+        RealT Dup_{0};
+        RealT femax_{0};
+        RealT femin_{0};
+        RealT Kpg_{0};
+        RealT Kig_{0};
+        RealT Pmax_{0};
+        RealT Pmin_{0};
+
+        IdxT  parameter_error_count_{0};
+        RealT system_to_component_base_{1};
+        RealT vcomp_off_{1};
+        RealT ref_off_{1};
+
+        ScalarT vref_set_{0};
+        ScalarT qref_set_{0};
+        ScalarT pplantref_set_{0};
+        ScalarT freq_set_{0};
+        ScalarT freqref_set_{0};
+
+        ComponentSignals<ScalarT, IdxT, RepcaInternalVariables, RepcaExternalVariables> signals_;
+        std::unique_ptr<MonitorT>                                                       monitor_;
+
+        std::vector<ScalarT> ws_;
+        std::vector<IdxT>    ws_indices_;
+      };
+    } // namespace Converter
+  } // namespace PhasorDynamics
+} // namespace GridKit
Original file line number	Diff line number	Diff line change
Expand Up		@@ -4,3 +4,4 @@
		# ]]

		add_subdirectory(REGCA)
		add_subdirectory(REPCA)