From 652004a2b3ff6057a3f94710c4b16f8af14040ee Mon Sep 17 00:00:00 2001
From: Steffen Meinecke <steffen.meinecke@uni-kassel.de>
Date: Mon, 6 Nov 2023 16:12:17 +0100
Subject: [PATCH] add parameter fuse_bus_column to
 merge_internal_net_and_equivalent_external_net()

---
 CHANGELOG.rst                                 |  1 +
 pandapower/grid_equivalents/get_equivalent.py | 27 ++++++++++---------
 pandapower/toolbox/grid_modification.py       |  2 +-
 3 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index 6eb76b3f1..524c91790 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -31,6 +31,7 @@ Change Log
 - [ADDED] matplotlib v3.8.0 support (fixed :code:`plotting_colormaps.ipynb`)
 - [CHANGED] PowerFactory converter - name :code:`for_name` as :code:`equipment` for all elements; also add to line
 - [ADDED] option to use a second tap changer for the trafo element
+- [CHANGED] parameters of function merge_internal_net_and_equivalent_external_net()
 - [FIXED] :code:`convert_format.py`: update the attributes of the characteristic objects to match the new characteristic
 
 
diff --git a/pandapower/grid_equivalents/get_equivalent.py b/pandapower/grid_equivalents/get_equivalent.py
index db3395602..f8cf31620 100644
--- a/pandapower/grid_equivalents/get_equivalent.py
+++ b/pandapower/grid_equivalents/get_equivalent.py
@@ -327,8 +327,7 @@ def get_equivalent(net, eq_type, boundary_buses, internal_buses,
 
 
 def merge_internal_net_and_equivalent_external_net(
-        net_eq, net_internal, eq_type, show_computing_time=False,
-        calc_volt_angles=False, **kwargs):
+        net_eq, net_internal, fuse_bus_column="auto", show_computing_time=False, **kwargs):
     """
     Merges the internal network and the equivalent external network.
     It is expected that the boundaries occur in both, equivalent net and
@@ -340,9 +339,11 @@ def merge_internal_net_and_equivalent_external_net(
 
         **net_internal** - internal area
 
-        **eq_type**  (str) - equivalent type, such as "rei", "ward" or "xward"
-
     OPTIONAL:
+        **fuse_bus_column**  (str, "auto) - the function expects boundary buses to be in net_eq and
+        in net_internal. These duplicate buses get fused. To identify these buses, the given column is used. Option "auto" provides backward compatibility which is: use "name_equivalent" if
+        existing and "name" otherwise
+
         **show_computing_time** (bool, False)
 
         ****kwargs** - key word arguments for pp.merge_nets()
@@ -368,17 +369,19 @@ def merge_internal_net_and_equivalent_external_net(
     merged_net = pp.merge_nets(
         net_internal, net_eq, validate=kwargs.pop("validate", False),
         net2_reindex_log_level=kwargs.pop("net2_reindex_log_level", "debug"), **kwargs)
-    try:
-        merged_net.gen.max_p_mw[-len(net_eq.gen.max_p_mw):] = net_eq.gen.max_p_mw.values
-        merged_net.gen.min_p_mw[-len(net_eq.gen.max_p_mw):] = net_eq.gen.min_p_mw.values
-    except:
-        pass
 
     # --- fuse or combine the boundary buses in external and internal nets
-    busname_col = "name_equivalent" if "name_equivalent" in merged_net.bus.columns.tolist() else "name"
+    if fuse_bus_column == "auto":
+        if fuse_bus_column in merged_net.bus.columns:
+            raise ValueError(
+                f"{fuse_bus_column=} is ambiguous since the column 'auto' exists in net.bus")
+        if "name_equivalent" in merged_net.bus.columns:
+            fuse_bus_column = "name_equivalent"
+        else:
+            fuse_bus_column = "name"
     for bus in boundary_buses_inclusive_bswitch:
-        name = merged_net.bus[busname_col].loc[bus]
-        target_buses = merged_net.bus.index[merged_net.bus[busname_col] == name]
+        name = merged_net.bus[fuse_bus_column].loc[bus]
+        target_buses = merged_net.bus.index[merged_net.bus[fuse_bus_column] == name]
         if len(target_buses) != 2:
             raise ValueError(
                 "The code expects all boundary buses to occur double. One because "
diff --git a/pandapower/toolbox/grid_modification.py b/pandapower/toolbox/grid_modification.py
index 872d8d2cb..c6fc5f911 100644
--- a/pandapower/toolbox/grid_modification.py
+++ b/pandapower/toolbox/grid_modification.py
@@ -141,7 +141,7 @@ def select_subnet(net, buses, include_switch_buses=False, include_results=False,
 
 def merge_nets(net1, net2, validate=True, merge_results=True, tol=1e-9, **kwargs):
     """Function to concatenate two nets into one data structure. The elements keep their indices
-    unless both nets have the same indices. In that case, net2 elements get reindex. The reindex
+    unless both nets have the same indices. In that case, net2 elements get reindexed. The reindex
     lookup of net2 elements can be retrieved by passing return_net2_reindex_lookup=True.
 
     Parameters