diff --git a/lightsim2grid/gridmodel/from_pandapower/_aux_add_trafo.py b/lightsim2grid/gridmodel/from_pandapower/_aux_add_trafo.py
index 56dd4ff..19da77b 100644
--- a/lightsim2grid/gridmodel/from_pandapower/_aux_add_trafo.py
+++ b/lightsim2grid/gridmodel/from_pandapower/_aux_add_trafo.py
@@ -61,14 +61,17 @@ def _aux_add_trafo(converter, model, pp_net, pp_to_ls):
         warnings.warn("There were some Nan in the pp_net.trafo[\"tap_side\"], they have been replaced by \"hv\"")
     is_tap_hv_side[~np.isfinite(is_tap_hv_side)] = True
 
-    if int(pp.__version__.split(".")[0]) < 3:
+    if "tap_phase_shifter" in pp_net.trafo:
         if np.any(pp_net.trafo["tap_phase_shifter"].values):
             raise RuntimeError("Ideal phase shifters are not modeled. Please remove all trafos with "
                                "pp_net.trafo[\"tap_phase_shifter\"] set to True.")
-    else:
-        if np.any(pp_net.trafo["tap_changer_type"].values == "Ideal") or \
-           np.any(pp_net.trafo3w["tap_changer_type"].values == "Ideal"):
-            raise RuntimeError("Ideal phase shifters are not modeled. Please remove all 2-winding or 3-winding trafos "
+    elif "tap_changer_type" in pp_net.trafo:
+        if np.any(pp_net.trafo["tap_changer_type"].values == "Ideal"):
+            raise RuntimeError("Ideal phase shifters are not modeled. Please remove all 2-winding trafos "
+                               "with \"tap_changer_type\" set to \"Ideal\".")
+    elif "tap_changer_type" in pp_net.trafo3w:
+        if np.any(pp_net.trafo3w["tap_changer_type"].values == "Ideal"):
+            raise RuntimeError("Ideal phase shifters are not modeled. Please remove all 3-winding trafos "
                                "with \"tap_changer_type\" set to \"Ideal\".")
 
     tap_angles_ = 1.0 * pp_net.trafo["tap_step_degree"].values