Merge pull request #417 from openego/featur/#382-add-check-in-topolog…

…y-whether-grid-contains-mesh

Featur/#382 add check in topology whether grid contains mesh

edisgo/network/topology.py

@@ -3135,6 +3135,9 @@ def check_integrity(self):
                 f"optimisation."
             )
 
+        # check for meshed grid
+        self.find_meshes()
+
     def assign_feeders(self, mode: str = "grid_feeder"):
         """
         Assigns MV or LV feeder to each bus and line, depending on the `mode`.
@@ -3203,3 +3206,31 @@ def aggregate_lv_grid_at_station(self, lv_grid_id: int | str) -> None:
 
     def __repr__(self):
         return f"Network topology {self.id}"
+
+    def find_meshes(edisgo_obj) -> list[list[int]] | None:
+        """
+        Find all meshes in the grid.
+
+        Parameters
+        ----------
+        edisgo_obj : EDisGo
+            EDisGo object.
+
+        Returns
+        -------
+        Optional[List[List[int]]]
+            List of all meshes in the grid.
+            Each mesh is represented as a list of node indices.
+            If no meshes are found, None is returned.
+        """
+        meshes = nx.cycle_basis(edisgo_obj.to_graph())
+        if meshes:
+            logger.warning(
+                "Grid contains mesh(es). Be aware, that the grid expansion methodology "
+                "is currently not able to handle meshes. Further, the optimisation of "
+                "flexibility dispatch is not exact in case of meshed grids, but can "
+                "still be used."
+            )
+            return meshes
+        else:
+            return None

edisgo/opf/powermodels_opf.py

@@ -4,26 +4,29 @@
 import subprocess
 import sys
 
+from typing import Optional
+
 import numpy as np
 
 from edisgo.flex_opt import exceptions
 from edisgo.io.powermodels_io import from_powermodels
+from edisgo.network.topology import Topology
 
 logger = logging.getLogger(__name__)
 
 
 def pm_optimize(
     edisgo_obj,
-    s_base=1,
-    flexible_cps=None,
-    flexible_hps=None,
-    flexible_loads=None,
-    flexible_storage_units=None,
-    opf_version=1,
-    method="soc",
-    warm_start=False,
-    silence_moi=False,
-):
+    s_base: int = 1,
+    flexible_cps: Optional[np.ndarray] = None,
+    flexible_hps: Optional[np.ndarray] = None,
+    flexible_loads: Optional[np.ndarray] = None,
+    flexible_storage_units: Optional[np.ndarray] = None,
+    opf_version: int = 1,
+    method: str = "soc",
+    warm_start: bool = False,
+    silence_moi: bool = False,
+) -> None:
     """
     Run OPF for edisgo object in julia subprocess and write results of OPF to edisgo
     object. Results of OPF are time series of operation schedules of flexibilities.
@@ -105,6 +108,7 @@ def pm_optimize(
         Default: True.
 
     """
+    Topology.find_meshes(edisgo_obj)
     opf_dir = os.path.dirname(os.path.abspath(__file__))
     solution_dir = os.path.join(opf_dir, "opf_solutions")
     pm, hv_flex_dict = edisgo_obj.to_powermodels(

tests/network/test_topology.py

@@ -1928,3 +1928,25 @@ def test_check_integrity(self, caplog):
         assert "There are lines with very short line lengths" in caplog.text
         assert "Very small values for impedance of lines" and line in caplog.text
         caplog.clear()
+
+    def test_find_meshes(self, caplog: pytest.LogCaptureFixture):
+        meshes = Topology.find_meshes(self.edisgo)
+        assert not meshes
+        self.edisgo.topology.add_line(
+            "Bus_GeneratorFluctuating_2",
+            "Bus_GeneratorFluctuating_6",
+            0.1,
+            x=0.1,
+            r=0.1,
+        )
+        meshes = Topology.find_meshes(self.edisgo)
+        assert len(meshes) == 1
+        assert "Bus_GeneratorFluctuating_2" in meshes[0]
+        assert "Bus_GeneratorFluctuating_6" in meshes[0]
+        self.edisgo.topology.add_line(
+            "Bus_BranchTee_LVGrid_2_3", "Bus_BranchTee_LVGrid_3_3", 0.1, x=0.1, r=0.1
+        )
+        meshes = Topology.find_meshes(self.edisgo)
+        assert len(meshes) == 2
+        assert "Bus_BranchTee_LVGrid_2_3" in meshes[1]
+        assert "Grid contains mesh(es)." in caplog.text