n1_mismatch.py

import pypowsybl
import numpy as np
import pandas as pd

def make_net_with_pst():
    net = pypowsybl.network.create_ieee57()
    net.create_buses(
        id="PSTBus",
        voltage_level_id="VL1"
    )
    net.create_lines(
        id="PSTLine",
        voltage_level1_id="VL1",
        bus1_id="PSTBus",
        voltage_level2_id="VL31",
        bus2_id="B31",
        r=0.0001,
        x=0.001,
        g1=0.0,
        b1=5,
        g2=0.0,
        b2=5,
    )
    net.create_2_windings_transformers(
        id="PST",
        voltage_level1_id="VL1",
        bus1_id="PSTBus",
        voltage_level2_id="VL1",
        bus2_id="B1",
        rated_u1=1,
        rated_u2=1,
        rated_s=np.nan,
        r=0.0,
        x=0.005,
        g=0.0,
        b=0.0,
    )
    ptc_df = pd.DataFrame.from_records(
        index='id', columns=['id', 'regulation_mode', 'low_tap', 'tap'],
        data=[('PST', 'FIXED_TAP', 0, 1)])
    steps_df = pd.DataFrame.from_records(
        index='id', columns=['id', 'b', 'g', 'r', 'x', 'rho', 'alpha'],
        data=[('PST', 0, 0, 0, 0, 1, 0),
                ('PST', 0, 0, 0, 0, 1, -8),
                ('PST', 0, 0, 0, 0, 1, -16)])
    net.create_phase_tap_changers(ptc_df=ptc_df, steps_df=steps_df)
    return net
    
net = make_net_with_pst()

analysis = pypowsybl.security.create_analysis()
monitored_branches = [i for i in net.get_branches().index if i != "PST"]
analysis.add_monitored_elements(branch_ids=monitored_branches)
analysis.add_single_element_contingency("PST")
res = analysis.run_dc(net)
p1_sec = res.branch_results.loc[("PST", "", monitored_branches)]["p1"].values


net.remove_elements("PST")
pypowsybl.loadflow.run_dc(net)
p1_ref = pd.concat([net.get_lines()["p1"], net.get_2_windings_transformers()["p1"]]).loc[monitored_branches].values

assert np.allclose(p1_sec, p1_ref)