feat: allow cross overs both in and out of the same compressor train …

…in a compressor system

This can be done if it is made sure that the compressor trains in the compressor system
are processed in the right order. You can only pass rates to a compressor train that
has not been processed yet. Hence, the indexes in the list specifying the cross overs
must be increasing (or zero, meaning no cross over).

src/libecalc/core/consumers/legacy_consumer/system/consumer_function.py

@@ -287,7 +287,7 @@ def calculate_operational_settings_after_cross_over(
                     f" {type(energy_usage_model).__name__} has not been implemented."
                     f" This should not happen. Please contact eCalc support."
                 )
-            transfer_rate = requested_rates[consumer_index] - consumer_maximum_rate
+            transfer_rate = rates_after_cross_over[consumer_index] - consumer_maximum_rate
             # Only transfer when max rate is exceeded
             transfer_rate = np.where(transfer_rate > 0, transfer_rate, 0)
 

src/libecalc/presentation/yaml/yaml_types/components/legacy/energy_usage_model/yaml_energy_usage_model_consumer_system.py

@@ -1,6 +1,6 @@
 from typing import Literal
 
-from pydantic import Field
+from pydantic import Field, model_validator
 
 from libecalc.presentation.yaml.yaml_types import YamlBase
 from libecalc.presentation.yaml.yaml_types.components.legacy.energy_usage_model.common import (
@@ -65,6 +65,24 @@ class YamlCompressorSystemOperationalSetting(YamlBase):
         description="Set suction pressure equal for all consumers in a consumer system operational setting. \n\n$ECALC_DOCS_KEYWORDS_URL/SUCTION_PRESSURE",
     )
 
+    @model_validator(mode="after")
+    def ensure_increasing_cross_over(self):
+        if self.crossover is None:
+            return self
+        for index, crossover in enumerate(self.crossover):
+            if crossover >= max(self.crossover[: index + 1]) or crossover == 0:
+                pass
+            else:
+                raise ValueError(
+                    f"Crossover: {self.crossover}\n"
+                    "To avoid loops and to avoid passing rates to compressor trains that have already been "
+                    "processed, the index of the crossovers should be either 0 or increasing in the list. "
+                    "This can probably be fixed by changing the order of the compressor trains in "
+                    "the compressor system. "
+                )
+
+        return self
+
 
 class YamlPumpSystemOperationalSettings(YamlCompressorSystemOperationalSetting):
     fluid_densities: list[YamlExpressionType] = Field(