Fix pandapower contingency analysis and Egret OPF on unrated branches

Egret/egret_mcp.py

@@ -36,6 +36,21 @@
 # Create an MCP server
 mcp = FastMCP("Egret Power System Analysis Server")
 
+# MATPOWER marks an unlimited branch with rateA/B/C = 0. Egret's own parser
+# stores that as None, which its models read as "no thermal limit", but they
+# index these keys directly, so a converter that leaves them out (powerio 0.11.5
+# does) fails with KeyError: 'rating_long_term'.
+_BRANCH_RATING_KEYS = ("rating_long_term", "rating_short_term", "rating_emergency")
+
+
+def _read_model_data(case_file: str) -> ModelData:
+    """Read a case and give unrated branches Egret's explicit None ratings."""
+    md = ModelData.read(case_file)
+    for branch in md.data.get("elements", {}).get("branch", {}).values():
+        for key in _BRANCH_RATING_KEYS:
+            branch.setdefault(key, None)
+    return md
+
 @mcp.tool()
 def solve_unit_commitment_problem(
     case_file: str,
@@ -65,7 +80,7 @@ def solve_unit_commitment_problem(
 
         with redirect_stdout(f_out), redirect_stderr(f_err):
             # Load the case file
-            md = ModelData.read(case_file)
+            md = _read_model_data(case_file)
 
             # Solve the unit commitment problem with solver_tee=False to silence solver output
             md_sol = solve_unit_commitment(
@@ -121,7 +136,7 @@ def solve_ac_opf(
 
         with redirect_stdout(f_out), redirect_stderr(f_err):
             # Load the case file
-            md = ModelData.read(case_file)
+            md = _read_model_data(case_file)
 
             # Solve AC OPF with solver_tee=False to silence solver output
             md_sol, results = solve_acopf(
@@ -178,7 +193,7 @@ def solve_dc_opf(
 
         with redirect_stdout(f_out), redirect_stderr(f_err):
             # Load the case file
-            md = ModelData.read(case_file)
+            md = _read_model_data(case_file)
 
             # Solve DC OPF with solver_tee=False to silence solver output
             md_sol, results = solve_dcopf(

pandapower/panda_mcp.py

@@ -1,4 +1,5 @@
 from typing import Dict, List, Optional, Tuple, Any, Union
+import copy
 import sys
 from pathlib import Path
 
@@ -265,7 +266,7 @@ def run_contingency_analysis(contingency_type: str = "N-1",
         net = _get_network()
 
         # Store original state
-        orig_net = net.deepcopy()
+        orig_net = copy.deepcopy(net)
         results = []
 
         # Define elements to analyze
@@ -276,7 +277,7 @@ def run_contingency_analysis(contingency_type: str = "N-1",
         for element_type in elements:
             for idx in net[element_type].index:
                 # Create contingency by taking element out of service
-                contingency_net = orig_net.deepcopy()
+                contingency_net = copy.deepcopy(orig_net)
                 contingency_net[element_type].at[idx, 'in_service'] = False
 
                 try:

tests/test_egret_unrated_branches.py

@@ -0,0 +1,69 @@
+"""Egret OPF must solve cases whose branches have no thermal rating (issue #128).
+
+MATPOWER writes rateA = 0 for an unlimited branch. powerio leaves the Egret
+rating keys out for those branches, and Egret's OPF models index them directly.
+"""
+
+import json
+from pathlib import Path
+import sys
+
+import pytest
+
+_CASE14 = Path(__file__).resolve().parents[1] / "Egret" / "pglib_opf_case14_ieee.m"
+
+
+@pytest.fixture()
+def egret_mcp(tmp_path, monkeypatch):
+    pytest.importorskip("egret")
+    monkeypatch.setenv("POWERMCP_HOME", str(tmp_path / "powermcp-home"))
+    from powermcp.registry import TOOLS
+
+    egret_dir = str(TOOLS["egret"].resolve_server_dir())
+    if egret_dir not in sys.path:
+        sys.path.insert(0, egret_dir)
+    import egret_mcp as _egret_mcp
+
+    return _egret_mcp
+
+
+def _unrate_every_other_branch(target: Path) -> int:
+    """Copy IEEE 14-bus with rateA/B/C = 0 on alternate branches; return how many."""
+    head, rest = _CASE14.read_text().split("mpc.branch = [", 1)
+    body, tail = rest.split("];", 1)
+    rows = [row.split() for row in body.strip().splitlines()]
+    for cols in rows[::2]:
+        cols[5:8] = ["0", "0", "0"]
+    table = "\n".join("\t" + "\t".join(cols) for cols in rows)
+    target.write_text(f"{head}mpc.branch = [\n{table}\n];{tail}")
+    return len(rows[::2])
+
+
+def test_dc_opf_solves_case_with_unrated_branches(egret_mcp, tmp_path):
+    pytest.importorskip("highspy")
+    case = tmp_path / "case14_unrated.m"
+    unrated = _unrate_every_other_branch(case)
+
+    loaded = egret_mcp.load_model_from_any(str(case))
+    assert loaded["status"] == "success", loaded
+
+    solved = egret_mcp.solve_dc_opf(loaded["case_file"], solver="highs")
+
+    assert solved["status"] == "success", solved
+    branches = solved["solution"]["elements"]["branch"]
+    assert sum(1 for b in branches.values() if b["rating_long_term"] is None) == unrated
+
+
+def test_missing_rating_keys_read_as_unlimited(egret_mcp, tmp_path):
+    case = tmp_path / "case.json"
+    case.write_text(json.dumps({
+        "elements": {"branch": {"1": {"from_bus": "1", "to_bus": "2"},
+                                "2": {"from_bus": "2", "to_bus": "3", "rating_long_term": 100.0}}},
+        "system": {"baseMVA": 100.0},
+    }))
+
+    branches = egret_mcp._read_model_data(str(case)).data["elements"]["branch"]
+
+    assert branches["1"]["rating_long_term"] is None
+    assert branches["1"]["rating_emergency"] is None
+    assert branches["2"]["rating_long_term"] == 100.0

tests/test_pandapower_contingency.py

@@ -0,0 +1,41 @@
+"""run_contingency_analysis must work with current pandapower (issue #127).
+
+pandapowerNet has no ``deepcopy`` method, so every call failed before the tool
+switched to ``copy.deepcopy``.
+"""
+
+import importlib.util
+from pathlib import Path
+import sys
+
+import pandapower.networks as pn
+
+_SERVER_PATH = Path(__file__).resolve().parents[1] / "pandapower" / "panda_mcp.py"
+
+
+def _load_server_like_runner():
+    # The runner puts only the server's own directory on sys.path.
+    server_dir = str(_SERVER_PATH.parent)
+    sys.path.insert(0, server_dir)
+    try:
+        spec = importlib.util.spec_from_file_location("powermcp_pandapower_server_contingency", _SERVER_PATH)
+        assert spec is not None and spec.loader is not None
+        module = importlib.util.module_from_spec(spec)
+        sys.modules[spec.name] = module
+        spec.loader.exec_module(module)
+        return module
+    finally:
+        sys.path.remove(server_dir)
+
+
+def test_n1_contingency_runs_on_case14_and_leaves_the_network_untouched(monkeypatch):
+    server = _load_server_like_runner()
+    net = pn.case14()
+    monkeypatch.setattr(server, "_current_net", net)
+
+    result = server.run_contingency_analysis()
+
+    assert result["status"] == "success", result
+    assert len(result["results"]) == len(net.line) + len(net.trafo)
+    assert any(r["converged"] for r in result["results"])
+    assert net.line.in_service.all() and net.trafo.in_service.all()