"Vsource.source" KeyError when instantiating NetworkAnalyzer on OpenDSS model

[petergoldthorpe]

Hi, I'm a colleague of @frederikgeth. We're trying to use DiTTo for a project that uses the metrics command with an opendss file, and we are running into the following error. We've narrowed down the problem to an issue with instantiating the NetworkAnalyzer model, and have been table to replicate for a test case that comes packaged with DiTTo. The test case is located at ./tests/readers/opendss/Powersource/test_powersource.dss

I have been using PyCharm to debug. My code is as follows:

from ditto.store import Store
from ditto.readers.opendss.read import Reader
from ditto.metrics.network_analysis import NetworkAnalyzer

model = Store()

filepath = 'C:/Users/GOL135/projects/ditto-public/ditto/tests/readers/opendss/Powersource/'
opendss_reader = Reader(master_file=filepath+'test_powersource.dss', buscoordinates_file=filepath+'buscoord.dss')
opendss_reader.parse(model)
# model.set_names()

network_analyst = NetworkAnalyzer(model=model) #<--- Error
network_analyst.compute_all_metrics()

Which throws the following error

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "C:\Program Files\JetBrains\PyCharm 2020.1.2\plugins\python\helpers\pydev\_pydev_bundle\pydev_umd.py", line 197, in runfile
    pydev_imports.execfile(filename, global_vars, local_vars)  # execute the script
  File "C:\Program Files\JetBrains\PyCharm 2020.1.2\plugins\python\helpers\pydev\_pydev_imps\_pydev_execfile.py", line 18, in execfile
    exec(compile(contents+"\n", file, 'exec'), glob, loc)
  File "C:/Users/GOL135/AppData/Roaming/JetBrains/PyCharm2020.1/scratches/scratch.py", line 12, in <module>
    network_analyst = NetworkAnalyzer(model=model)
  File "C:\Users\GOL135\projects\ditto-public\ditto\ditto\metrics\network_analysis.py", line 160, in __init__
    modifier.set_nominal_voltages()
  File "C:\Users\GOL135\projects\ditto-public\ditto\ditto\modify\system_structure.py", line 583, in set_nominal_voltages
    upstream_transformer_name = self.G.get_upstream_transformer(
  File "C:\Users\GOL135\projects\ditto-public\ditto\ditto\network\network.py", line 357, in get_upstream_transformer
    edge_type = edge_equipment[(curr[0], curr_node)]
KeyError: ('Vsource.source', 'sourcebus')

The same error is thrown when using the model.set_names() method. We have used the traceback to find the error in the ./ditto/network/network.py file.

def get_upstream_transformer(self, model, node):

    curr_node = node
    curr = list(self.digraph.predecessors(node))
    edge_equipment = nx.get_edge_attributes(self.digraph, "equipment")
    edge_equipment_name = nx.get_edge_attributes(self.digraph, "equipment_name")
    # import pdb; pdb.set_trace()
    while curr != []:
        edge_type = edge_equipment[(curr[0], curr_node)]
        if edge_type == "PowerTransformer":
            return edge_equipment_name[(curr[0], curr_node)]
        curr_node = curr[0]  # assuming that the network is a DAG
        curr = list(self.digraph.predecessors(curr_node))
    return None

Here the code throws a KeyError. The edge_equipment is a dictionary of tuples, and the code fails when it attempts to call a tuple which contains 'Vsource.source' as the first element. No such element exists in the edge_equipment dictionary.

---

In the ./tests/readers/opendss/Powersource/test_powersource.py there is a function which reads in an OpenDSS file and asserts that

model["Vsource.source"].name == "Vsource.source"

This assertion passes with no error on my machine, but I still encounter the KeyError when using my own code as when I print model.name I encounter:

AttributeError: 'Store' object has no attribute 'name'

Any advice would be welcome. Kind regards, Peter

[kdheepak]

Thanks for the detailed issue.

I think in your code where you use model.name, you are instead doing store.name, and that what is giving this error. Can you try print(store.elements)? That should return a list of "models".

[petergoldthorpe]

Sure, I've tried printing the commands from my code. The output is as follows:

>>>print(model)
<ditto.store.Store(elements=0, models=5) object at 0x14b3337dbb0>

>>>print(model.elements)
[]

>>>print(model.models)
(<ditto.models.power_source.PowerSource object at 0x0000014B3337D5B0>, ... ) #tuple of length 5

>>>for idx, mod in enumerate(model.models):
>>>    try:
>>>        print(idx, mod.name)
>>>    except AttributeError as e:
>>>        print(idx, 'No name:', e)

0 Vsource.source
1 No name: 'Position' object has no attribute 'name'
2 sourcebus_src
3 sourcebus
4 No name: 'Position' object has no attribute 'name'

These print statements are executed before the NetworkAnalyzer is initialized. The KeyError is thrown as described earlier.

I should also mention that I am using Python 3.8.3 and the latest version of DiTTo.

[thaitranp]

I'm also running into the same key error issue when trying to call build_networkx() for the ephasor conversion test.

[jnh277]

same issue when trying to use build_networkx()