Add support for fixed time steps with IDA

CHANGELOG.md

@@ -59,6 +59,7 @@
 - Remove data copying between system and components in `PowerElectronics` models.
 - Added multi-contingency analysis application.
 - Added `BusToSignalAdapter` component for communicating bus voltages and injection currents.
+- Added support for running IDA with fixed time steps
 
 ## v0.1
 

GridKit/Model/Evaluator.hpp

@@ -33,12 +33,23 @@ namespace GridKit
       {
       }
 
-      virtual int allocate()          = 0;
-      virtual int initialize()        = 0;
-      virtual int tagDifferentiable() = 0;
-      virtual int evaluateResidual()  = 0;
-      virtual int evaluateJacobian()  = 0;
-      virtual int evaluateIntegrand() = 0;
+      virtual int allocate()                          = 0;
+      virtual int initialize()                        = 0;
+      virtual int tagDifferentiable()                 = 0;
+      /**
+       * @brief Compute the absolute tolerance for each variable in the model
+       *
+       * @param rel_tol The relative tolerance which can be used to pick the
+       *        absolute tolerance.
+       * @return int 0 if successful, non-zero otherwise.
+       *
+       * This represents a "noise" level close to zero for which pure relative
+       * error cannot be used.
+       */
+      virtual int setAbsoluteTolerance(RealT rel_tol) = 0;
+      virtual int evaluateResidual()                  = 0;
+      virtual int evaluateJacobian()                  = 0;
+      virtual int evaluateIntegrand()                 = 0;
 
       virtual int initializeAdjoint()        = 0;
       virtual int evaluateAdjointResidual()  = 0;
@@ -103,11 +114,26 @@ namespace GridKit
        */
       virtual bool hasJacobian() = 0;
 
-      virtual IdxT sizeQuadrature()                              = 0;
-      virtual IdxT sizeParams()                                  = 0;
-      virtual void updateTime(RealT t, RealT a)                  = 0;
-      virtual void setTolerances(RealT& rtol, RealT& atol) const = 0;
-      virtual void setMaxSteps(IdxT& msa) const                  = 0;
+      virtual IdxT sizeQuadrature()             = 0;
+      virtual IdxT sizeParams()                 = 0;
+      virtual void updateTime(RealT t, RealT a) = 0;
+
+      /**
+       * @brief Get the absolute tolerance for each variable in the model
+       *
+       * @return a reference to the absolute tolerance vector.
+       *
+       * @pre `setAbsoluteTolerance` must have been called first.
+       */
+      virtual std::vector<ScalarT>&       absoluteTolerance()       = 0;
+      /**
+       * @brief Get the absolute tolerance for each variable in the model
+       *
+       * @return a const reference to the absolute tolerance vector.
+       *
+       * @pre `setAbsoluteTolerance` must have been called first.
+       */
+      virtual const std::vector<ScalarT>& absoluteTolerance() const = 0;
 
       virtual std::vector<ScalarT>&       y()       = 0;
       virtual const std::vector<ScalarT>& y() const = 0;

GridKit/Model/PhasorDynamics/Branch/Branch.hpp

@@ -73,6 +73,7 @@ namespace GridKit
       virtual int allocate() override final;
       virtual int initialize() override final;
       virtual int tagDifferentiable() override final;
+      virtual int setAbsoluteTolerance(RealT rel_tol) override final;
       virtual int evaluateResidual() override final;
       virtual int evaluateJacobian() override final;
 

GridKit/Model/PhasorDynamics/Branch/BranchImpl.hpp

@@ -140,6 +140,24 @@ namespace GridKit
       return 0;
     }
 
+    /**
+     * @brief Compute the absolute tolerance for each variable in the model
+     *
+     * @param rel_tol The relative tolerance which can be used to pick the
+     *        absolute tolerance.
+     * @tparam ScalarT Scalar data type
+     * @tparam IdxT Index data type
+     * @return int 0 if successful, non-zero otherwise.
+     *
+     * This represents a "noise" level close to zero for which pure relative
+     * error cannot be used.
+     */
+    template <class ScalarT, typename IdxT>
+    int Branch<ScalarT, IdxT>::setAbsoluteTolerance(RealT)
+    {
+      return 0;
+    }
+
     /**
      * @brief Bus 1 residual contribution from bus 1 variables
      *

GridKit/Model/PhasorDynamics/Bus/Bus.hpp

@@ -28,6 +28,7 @@ namespace GridKit
       using BusBase<ScalarT, IdxT>::J_cols_buffer_;
       using BusBase<ScalarT, IdxT>::J_vals_buffer_;
       using BusBase<ScalarT, IdxT>::tag_;
+      using BusBase<ScalarT, IdxT>::abs_tol_;
       using BusBase<ScalarT, IdxT>::variable_indices_;
       using BusBase<ScalarT, IdxT>::residual_indices_;
 
@@ -44,6 +45,7 @@ namespace GridKit
       virtual int setBusID(IdxT) override final;
       virtual int allocate() override final;
       virtual int tagDifferentiable() override final;
+      virtual int setAbsoluteTolerance(RealT rel_tol) override final;
       virtual int initialize() override final;
       virtual int evaluateResidual() override final;
       virtual int evaluateJacobian() override final;

GridKit/Model/PhasorDynamics/Bus/BusImpl.hpp

@@ -86,6 +86,7 @@ namespace GridKit
       y_.resize(size);
       yp_.resize(size);
       tag_.resize(size);
+      abs_tol_.resize(size);
       variable_indices_.resize(size);
       residual_indices_.resize(size);
 
@@ -120,6 +121,25 @@ namespace GridKit
       return 0;
     }
 
+    /**
+     * @brief Compute the absolute tolerance for each variable in the model
+     *
+     * @param rel_tol The relative tolerance which can be used to pick the
+     *        absolute tolerance.
+     * @tparam ScalarT Scalar data type
+     * @tparam IdxT Index data type
+     * @return int 0 if successful, non-zero otherwise.
+     *
+     * This represents a "noise" level close to zero for which pure relative
+     * error cannot be used.
+     */
+    template <class ScalarT, typename IdxT>
+    int Bus<ScalarT, IdxT>::setAbsoluteTolerance(RealT rel_tol)
+    {
+      std::fill(abs_tol_.begin(), abs_tol_.end(), rel_tol);
+      return 0;
+    }
+
     /*!
      * @brief initialize method sets bus variables to stored initial values.
      */

GridKit/Model/PhasorDynamics/Bus/BusInfinite.hpp

@@ -38,6 +38,7 @@ namespace GridKit
       virtual int setBusID(IdxT) override final;
       virtual int allocate() override final;
       virtual int tagDifferentiable() override final;
+      virtual int setAbsoluteTolerance(RealT rel_tol) override final;
       virtual int initialize() override final;
       virtual int evaluateResidual() override final;
       virtual int evaluateJacobian() override final;

GridKit/Model/PhasorDynamics/Bus/BusInfiniteImpl.hpp

@@ -95,6 +95,24 @@ namespace GridKit
       return 0;
     }
 
+    /**
+     * @brief Compute the absolute tolerance for each variable in the model
+     *
+     * @param rel_tol The relative tolerance which can be used to pick the
+     *        absolute tolerance.
+     * @tparam ScalarT Scalar data type
+     * @tparam IdxT Index data type
+     * @return int 0 if successful, non-zero otherwise.
+     *
+     * This represents a "noise" level close to zero for which pure relative
+     * error cannot be used.
+     */
+    template <class ScalarT, typename IdxT>
+    int BusInfinite<ScalarT, IdxT>::setAbsoluteTolerance(RealT)
+    {
+      return 0;
+    }
+
     /*!
      * @brief initialize method sets bus variables to stored initial values.
      */

GridKit/Model/PhasorDynamics/BusFault/BusFault.hpp

@@ -52,6 +52,7 @@ namespace GridKit
       int allocate() override final;
       int initialize() override final;
       int tagDifferentiable() override final;
+      int setAbsoluteTolerance(RealT rel_tol) override final;
       int evaluateResidual() override final;
       int evaluateJacobian() override final;
 

GridKit/Model/PhasorDynamics/BusFault/BusFaultImpl.hpp

@@ -141,6 +141,24 @@ namespace GridKit
       return 0;
     }
 
+    /**
+     * @brief Compute the absolute tolerance for each variable in the model
+     *
+     * @param rel_tol The relative tolerance which can be used to pick the
+     *        absolute tolerance.
+     * @tparam ScalarT Scalar data type
+     * @tparam IdxT Index data type
+     * @return int 0 if successful, non-zero otherwise.
+     *
+     * This represents a "noise" level close to zero for which pure relative
+     * error cannot be used.
+     */
+    template <class ScalarT, typename IdxT>
+    int BusFault<ScalarT, IdxT>::setAbsoluteTolerance(RealT)
+    {
+      return 0;
+    }
+
     /**
      * @brief Bus residual
      *

GridKit/Model/PhasorDynamics/Exciter/IEEET1/Ieeet1.hpp

@@ -73,6 +73,7 @@ namespace GridKit
         using Component<ScalarT, IdxT>::nnz_;
         using Component<ScalarT, IdxT>::size_;
         using Component<ScalarT, IdxT>::tag_;
+        using Component<ScalarT, IdxT>::abs_tol_;
         using Component<ScalarT, IdxT>::time_;
         using Component<ScalarT, IdxT>::y_;
         using Component<ScalarT, IdxT>::yp_;
@@ -105,6 +106,7 @@ namespace GridKit
         int verify() const override final;
         int initialize() override final;
         int tagDifferentiable() override final;
+        int setAbsoluteTolerance(RealT rel_tol) override final;
         int evaluateResidual() override final;
         int evaluateJacobian() override final;
 

GridKit/Model/PhasorDynamics/Exciter/IEEET1/Ieeet1Impl.hpp

@@ -122,6 +122,7 @@ namespace GridKit
         y_.resize(size);
         yp_.resize(size);
         tag_.resize(size);
+        abs_tol_.resize(size);
         variable_indices_.resize(size);
         residual_indices_.resize(size);
 
@@ -283,6 +284,25 @@ namespace GridKit
         return 0;
       }
 
+      /**
+       * @brief Compute the absolute tolerance for each variable in the model
+       *
+       * @param rel_tol The relative tolerance which can be used to pick the
+       *        absolute tolerance.
+       * @tparam ScalarT Scalar data type
+       * @tparam IdxT Index data type
+       * @return int 0 if successful, non-zero otherwise.
+       *
+       * This represents a "noise" level close to zero for which pure relative
+       * error cannot be used.
+       */
+      template <class ScalarT, typename IdxT>
+      int Ieeet1<ScalarT, IdxT>::setAbsoluteTolerance(RealT rel_tol)
+      {
+        std::fill(abs_tol_.begin(), abs_tol_.end(), rel_tol);
+        return 0;
+      }
+
       /**
        * @brief Internal Residual
        *

GridKit/Model/PhasorDynamics/Exciter/SEXS-PTI/SexsPti.hpp

@@ -60,6 +60,7 @@ namespace GridKit
         using Component<ScalarT, IdxT>::nnz_;
         using Component<ScalarT, IdxT>::size_;
         using Component<ScalarT, IdxT>::tag_;
+        using Component<ScalarT, IdxT>::abs_tol_;
         using Component<ScalarT, IdxT>::time_;
         using Component<ScalarT, IdxT>::y_;
         using Component<ScalarT, IdxT>::yp_;
@@ -87,6 +88,7 @@ namespace GridKit
         int verify() const override final;
         int initialize() override final;
         int tagDifferentiable() override final;
+        int setAbsoluteTolerance(RealT rel_tol) override final;
         int evaluateResidual() override final;
         int evaluateJacobian() override final;
 

GridKit/Model/PhasorDynamics/Exciter/SEXS-PTI/SexsPtiImpl.hpp

@@ -62,6 +62,7 @@ namespace GridKit
         y_.resize(size);
         yp_.resize(size);
         tag_.resize(size);
+        abs_tol_.resize(size);
         variable_indices_.resize(size);
         residual_indices_.resize(size);
 
@@ -180,6 +181,25 @@ namespace GridKit
         return 0;
       }
 
+      /**
+       * @brief Compute the absolute tolerance for each variable in the model
+       *
+       * @param rel_tol The relative tolerance which can be used to pick the
+       *        absolute tolerance.
+       * @tparam ScalarT Scalar data type
+       * @tparam IdxT Index data type
+       * @return int 0 if successful, non-zero otherwise.
+       *
+       * This represents a "noise" level close to zero for which pure relative
+       * error cannot be used.
+       */
+      template <class ScalarT, typename IdxT>
+      int SexsPti<ScalarT, IdxT>::setAbsoluteTolerance(RealT rel_tol)
+      {
+        std::fill(abs_tol_.begin(), abs_tol_.end(), rel_tol);
+        return 0;
+      }
+
       template <class ScalarT, typename IdxT>
       __attribute__((always_inline)) inline int SexsPti<ScalarT, IdxT>::evaluateInternalResidual(
           ScalarT* y,

GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1.hpp

@@ -64,6 +64,7 @@ namespace GridKit
         using Component<ScalarT, IdxT>::nnz_;
         using Component<ScalarT, IdxT>::size_;
         using Component<ScalarT, IdxT>::tag_;
+        using Component<ScalarT, IdxT>::abs_tol_;
         using Component<ScalarT, IdxT>::time_;
         using Component<ScalarT, IdxT>::y_;
         using Component<ScalarT, IdxT>::yp_;
@@ -91,6 +92,7 @@ namespace GridKit
         int verify() const override final;
         int initialize() override final;
         int tagDifferentiable() override final;
+        int setAbsoluteTolerance(RealT) override final;
         int evaluateResidual() override final;
 
         // Still to be implemented

GridKit/Model/PhasorDynamics/Governor/Tgov1/Tgov1Impl.hpp

@@ -140,6 +140,7 @@ namespace GridKit
         y_.resize(size);
         yp_.resize(size);
         tag_.resize(size);
+        abs_tol_.resize(size);
         variable_indices_.resize(size);
         residual_indices_.resize(size);
 
@@ -232,6 +233,25 @@ namespace GridKit
         return 0;
       }
 
+      /**
+       * @brief Compute the absolute tolerance for each variable in the model
+       *
+       * @param rel_tol The relative tolerance which can be used to pick the
+       *        absolute tolerance.
+       * @tparam ScalarT Scalar data type
+       * @tparam IdxT Index data type
+       * @return int 0 if successful, non-zero otherwise.
+       *
+       * This represents a "noise" level close to zero for which pure relative
+       * error cannot be used.
+       */
+      template <class ScalarT, typename IdxT>
+      int Tgov1<ScalarT, IdxT>::setAbsoluteTolerance(RealT rel_tol)
+      {
+        std::fill(abs_tol_.begin(), abs_tol_.end(), rel_tol);
+        return 0;
+      }
+
       /**
        * @brief Internal residuals
        *