# Create two buses
source_bus = Bus(id="sb", phases="abcn")
load_bus = Bus(id="lb", phases="abcn")

# Define the reference of potentials to be the neutral of the source bus
ground = Ground(id="gnd")
pref = PotentialRef(id="pref", element=ground)  # Fix the potential of the ground at 0 V
ground.connect(source_bus, phase="n")

# Create a LV source at the first bus
un = 400 / np.sqrt(3)  # Volts (phase-to-neutral because the source is connected to the neutral)
source_voltages = [un, un * np.exp(-2j * np.pi / 3), un * np.exp(2j * np.pi / 3)]
vs = VoltageSource(id="vs", bus=source_bus, phases="abcn", voltages=source_voltages)

# Add a load at the second bus
load = PowerLoad(id="load", bus=load_bus, phases="abcn", powers=[10e3 + 0j, 10e3, 10e3])  # VA

# Add a LV line between the source bus and the load bus
lp = LineParameters("lp", z_line=(0.1 + 0.0j) * np.eye(4, dtype=complex))  # R = 0.1 Ohm/km, X = 0
line = Line(id="line", bus1=source_bus, bus2=load_bus, phases="abcn", parameters=lp, length=2.0)