Create network elements

[EtienneLt]

Please check if the PR fulfills these requirements (please use '[x]' to check the checkboxes, or submit the PR and then click the checkboxes)

• The commit message follows our guidelines
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

What kind of change does this PR introduce? (Bug fix, feature, docs update, ...)

Feature.

What is the current behavior? (You can also link to an open issue here)

Network elements cannot be created through python methods.

What is the new behavior (if this is a feature change)?

We can now create network elements, for example:

def test_create_network_and_run_loadflow():
    n = pn.create_empty()
    stations = pd.DataFrame.from_records(index='id', data=[
        {'id': 'S1', 'country': 'BE'},
        {'id': 'S2', 'country': 'DE'}
    ])
    n.create_substations(stations)

    voltage_levels = pd.DataFrame.from_records(index='id', data=[
        {'substation_id': 'S1', 'id': 'VL1', 'topology_kind': 'BUS_BREAKER', 'nominal_v': 400},
        {'substation_id': 'S2', 'id': 'VL2', 'topology_kind': 'BUS_BREAKER', 'nominal_v': 400},
    ])
    n.create_voltage_levels(voltage_levels)

    buses = pd.DataFrame.from_records(index='id', data=[
        {'voltage_level_id': 'VL1', 'id': 'B1'},
        {'voltage_level_id': 'VL2', 'id': 'B2'},
    ])
    n.create_buses(buses)

    lines = pd.DataFrame.from_records(index='id', data=[
        {'id': 'LINE', 'voltage_level1_id': 'VL1', 'voltage_level2_id': 'VL2', 'bus1_id': 'B1', 'bus2_id': 'B2',
         'r': 0.1, 'x': 1.0, 'g1': 0, 'b1': 1e-6, 'g2': 0, 'b2': 1e-6}
    ])
    n.create_lines(lines)

    loads = pd.DataFrame.from_records(index='id', data=[
        {'voltage_level_id': 'VL2', 'id': 'LOAD', 'bus_id': 'B2', 'p0': 100, 'q0': 10}
    ])
    n.create_loads(loads)

    generators = pd.DataFrame.from_records(index='id', data=[
        {'voltage_level_id': 'VL1', 'id': 'GEN', 'bus_id': 'B1', 'target_p': 100, 'min_p': 0, 'max_p': 200,
         'target_v': 400, 'voltage_regulator_on': True}
    ])
    n.create_generators(generators)

    import pypowsybl.loadflow as lf
    lf.run_ac(n)

    line = n.get_lines().loc['LINE']
    assert line.p2 == pytest.approx(-100, abs=1e-2)
    assert line.q2 == pytest.approx(-10, abs=1e-2)
    assert line.p1 == pytest.approx(100, abs=1e-1)
    assert line.q1 == pytest.approx(9.7, abs=1e-1)

[sonarcloud]

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3.6% Duplication

[annetill]

@EtienneLt it seems that your PR is needed for long-term studies. Do you think that you can rework on that in the next following months? It would be great!

[EtienneLt]

yes no problem

[sylvlecl]

Actually something is missing for node breaker topologies:
we cannot create "internal connections". Still a todo.

[annetill]

Be careful here: if not present, I think that you will have NaN values.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

Just a general question: when you only fill the bus id, and not the connectable bus id, what is happening ? And if you want a disconnected battery, you will have to fill the connectable bus only ?

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

I think that we have to think about g and a b default values equals to zero.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

I think that we have to think about default values for minP and maxP (it seems to be NaN in powsybl-core), right?

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

Default value for maxP ?

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

I think that for line, we must think about by default having b1, b2, g1 and g2 equal to zero.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

The target deadband could be at zero by default to ease understanding.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

For phase tap changers, I think that we can provide a lot of default values and maybe allow only angles to be set.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

On load can be to true by default, and the target deadband could be to zero. For the ratio tap changer, I think that it could be great to have the possibility to set only ratios.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

In general, for shunt, it could be great to have a way to only set a B from a dataframe, that will create a shunt understandable by Powsybl.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

In general: it always has been strange to be to give both voltage level id and bus id. It will be very great to have the possibility to give only busId to create equipments in the network, and to have a way to retrieve the voltage level. It is a bit confusing to expose the complexity of IIDM in python.

[sylvlecl]

See discussion synthesis about default values in comment below.

[annetill]

Same remark as lines. And maybe rated U1 and U2 could also have default values equal to nominal voltage at ends. What do you think ?

[sylvlecl]

See discussion synthesis about default values in comment below.

[sylvlecl]

Just writing down the outcome of the discussions about default values:

currently, we inherit the behaviour of powsybl-core adders.
The implementation of default values will be more valuable in powsybl-core than in pypowsybl, because it will benefit to all users.

Therefore, unless there is something specific that the python community asks for, and that we really don't want to implement in powsybl-core, we'll keep it this way.

[annetill]

I am going to try to put some default values in the adders of powsybl-core, and we will see what remains for pypowsybl !

[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

97.5% Coverage
0.0% Duplication