def test_transformer_type():
Vhv = 24 # primary voltage in kV
Vlv = 0.42 # secondary voltage kV
Sn = 100 # nominal power in MVA
Psc = 300 # short circuit power (copper losses) kW
P0 = 100 # no load power (iron losses) kW
V0 = 0.8 # no load voltage in %
Vsc = 8 # short-circuit voltage in %
obj = TransformerType(hv_nominal_voltage=Vhv,
lv_nominal_voltage=Vlv,
nominal_power=Sn,
copper_losses=Psc,
short_circuit_voltage=Vsc,
iron_losses=P0,
no_load_current=V0,
gr_hv1=0.5, gx_hv1=0.5)
Sbase = 100
z_series, zsh = obj.get_impedances()
# Change the base to the system base power
base_change = obj.rating / Sbase
z_series *= base_change
zsh *= base_change
print(z_series, 'Ys ->', 1 / z_series)
print(zsh, '-> y_sh ->', 1 / zsh)
def test_reverse_transformer():
# ------------------------------------------------------------------------------------------------------------------
# Revert the calcs
# ------------------------------------------------------------------------------------------------------------------
Vf = 11
Vt = 132
G = 0
B = 0
R = 0
X = 0.115
Sn = 30
print()
print('R', R)
print('X', X)
print('G', G)
print('B', B)
zsc = sqrt(R * R + 1 / (X * X))
Vsc = 100.0 * zsc
Pcu = R * Sn * 1000.0
if abs(G) > 0.0 and abs(B) > 0.0:
zl = 1.0 / complex(G, B)
rfe = zl.real
xm = zl.imag
Pfe = 1000.0 * Sn / rfe
k = 1 / (rfe * rfe) + 1 / (xm * xm)
I0 = 100.0 * sqrt(k)
else:
Pfe = 1e-20
I0 = 1e-20
print('Vsc', Vsc)
print('Pcu', Pcu)
print('I0', I0)
print('Pfe', Pfe)
tpe2 = TransformerType(hv_nominal_voltage=Vf,
lv_nominal_voltage=Vt,
nominal_power=Sn,
copper_losses=Pcu,
iron_losses=Pfe,
no_load_current=I0,
short_circuit_voltage=Vsc,
gr_hv1=0.5,
gx_hv1=0.5)
z2, zl2 = tpe2.get_impedances()
# print(z2)
# print(1/zl2)
yl = 1 / zl2
print()
print('R', z2.real)
print('X', z2.imag)
print('G', yl.real)
print('B', yl.imag)
def get_transformer_catalogue():
path = os.path.dirname(os.path.abspath(__file__))
fname = os.path.join(path, '..', '..', 'data', 'transformers.csv')
if os.path.exists(fname):
df = pd.read_csv(fname)
lst = list()
for i, item in df.iterrows():
tpe = TransformerType(
hv_nominal_voltage=item['HV (kV)'],
lv_nominal_voltage=item['LV (kV)'],
nominal_power=item['Rate (MVA)'],
copper_losses=item['Copper losses (kW)'],
iron_losses=item['No load losses (kW)'],
no_load_current=item['No load current (%)'],
short_circuit_voltage=item['V short circuit (%)'],
gr_hv1=0.5,
gx_hv1=0.5,
name=item['Name'])
lst.append(tpe)
return lst
else:
return list()
def get_template(self):
"""
Fabricate template values from the branch values
:return: TransformerType instance
"""
eps = 1e-20
Vf = self.transformer_obj.bus_from.Vnom # kV
Vt = self.transformer_obj.bus_to.Vnom # kV
Sn = self.sn_spinner.value() + eps # MVA
Pcu = self.pcu_spinner.value() + eps # kW
Pfe = self.pfe_spinner.value() + eps # kW
I0 = self.I0_spinner.value() + eps # %
Vsc = self.vsc_spinner.value() # %
Pfe = eps if Pfe == 0.0 else Pfe
I0 = eps if I0 == 0.0 else I0
tpe = TransformerType(hv_nominal_voltage=Vf,
lv_nominal_voltage=Vt,
nominal_power=Sn,
copper_losses=Pcu,
iron_losses=Pfe,
no_load_current=I0,
short_circuit_voltage=Vsc,
gr_hv1=0.5,
gx_hv1=0.5)
return tpe
def test_transformer_type():
Vhv = 21 # primary voltage in kV
Vlv = 0.42 # secondary voltage kV
Sn = 0.25 # nominal power in MVA
Pcu = 2.35 # short circuit power (copper losses) kW
Pfe = 0.27 # no load power (iron losses) kW
I0 = 1.0 # no load voltage in %
Vsc = 4.6 # short-circuit voltage in %
obj = TransformerType(hv_nominal_voltage=Vhv,
lv_nominal_voltage=Vlv,
nominal_power=Sn,
copper_losses=Pcu,
short_circuit_voltage=Vsc,
iron_losses=Pfe,
no_load_current=I0,
gr_hv1=0.5, gx_hv1=0.5)
Sbase = 100
z_series, y_shunt = obj.get_impedances(VH=Vhv, VL=Vlv, Sbase=Sbase)
assert np.allclose(z_series, 3.76+18.01j, rtol=0.01)
assert np.allclose(y_shunt, 2.6532597915358445e-06-2.456722029199863e-05j, rtol=0.01)
def test_basic():
"""
Basic GridCal test, also useful for a basic tutorial. In this case the
magnetizing branch of the transformers is neglected by inputting 1e-20
excitation current and iron core losses.
The results are identical to ETAP's, which always uses this assumption in
balanced load flow calculations.
"""
test_name = "test_basic"
grid = MultiCircuit(name=test_name)
S_base = 100 # MVA
grid.Sbase = S_base
grid.time_profile = None
grid.logger = list()
# Create buses
POI = Bus(
name="POI",
vnom=100, #kV
is_slack=True)
grid.add_bus(POI)
B_C3 = Bus(name="B_C3", vnom=10) #kV
grid.add_bus(B_C3)
B_MV_M32 = Bus(name="B_MV_M32", vnom=10) #kV
grid.add_bus(B_MV_M32)
B_LV_M32 = Bus(name="B_LV_M32", vnom=0.6) #kV
grid.add_bus(B_LV_M32)
# Create voltage controlled generators (or slack, a.k.a. swing)
UT = Generator(name="Utility")
UT.bus = POI
grid.add_generator(POI, UT)
# Create static generators (with fixed power factor)
M32 = StaticGenerator(
name="M32",
P=4.2, # MW
Q=0.0j) # MVAR
M32.bus = B_LV_M32
grid.add_static_generator(B_LV_M32, M32)
# Create transformer types
s = 5 # MVA
z = 8 # %
xr = 40
SS = TransformerType(
name="SS",
hv_nominal_voltage=100, # kV
lv_nominal_voltage=10, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / S_base,
iron_losses=1e-20,
no_load_current=1e-20,
short_circuit_voltage=z)
grid.add_transformer_type(SS)
s = 5 # MVA
z = 6 # %
xr = 20
PM = TransformerType(
name="PM",
hv_nominal_voltage=10, # kV
lv_nominal_voltage=0.6, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / S_base,
iron_losses=1e-20,
no_load_current=1e-20,
short_circuit_voltage=z)
grid.add_transformer_type(PM)
# Create branches
X_C3 = Branch(bus_from=POI,
bus_to=B_C3,
name="X_C3",
branch_type=BranchType.Transformer,
template=SS)
grid.add_branch(X_C3)
C_M32 = Branch(bus_from=B_C3,
bus_to=B_MV_M32,
name="C_M32",
r=0.784,
x=0.174)
grid.add_branch(C_M32)
X_M32 = Branch(bus_from=B_MV_M32,
bus_to=B_LV_M32,
name="X_M32",
branch_type=BranchType.Transformer,
template=PM)
grid.add_branch(X_M32)
# Apply templates (device types)
grid.apply_all_branch_types()
print("Buses:")
for i, b in enumerate(grid.buses):
print(f" - bus[{i}]: {b}")
print()
options = PowerFlowOptions(SolverType.LM,
verbose=True,
initialize_with_existing_solution=True,
multi_core=True,
control_q=ReactivePowerControlMode.Direct,
tolerance=1e-6,
max_iter=99)
power_flow = PowerFlow(grid, options)
power_flow.run()
approx_volt = [round(100 * abs(v), 1) for v in power_flow.results.voltage]
solution = [
100.0, 99.6, 102.7, 102.9
] # Expected solution from GridCal and ETAP 16.1.0, for reference
print()
print(f"Test: {test_name}")
print(f"Results: {approx_volt}")
print(f"Solution: {solution}")
print()
print("Generators:")
for g in grid.get_generators():
print(f" - Generator {g}: q_min={g.Qmin}pu, q_max={g.Qmax}pu")
print()
print("Branches:")
for b in grid.branches:
print(f" - {b}:")
print(f" R = {round(b.R, 4)} pu")
print(f" X = {round(b.X, 4)} pu")
print(f" X/R = {round(b.X/b.R, 1)}")
print(f" G = {round(b.G, 4)} pu")
print(f" B = {round(b.B, 4)} pu")
print()
print("Transformer types:")
for t in grid.transformer_types:
print(
f" - {t}: Copper losses={int(t.Pcu)}kW, Iron losses={int(t.Pfe)}kW, SC voltage={t.Vsc}%"
)
print()
print("Losses:")
for i in range(len(grid.branches)):
print(
f" - {grid.branches[i]}: losses={1000*round(power_flow.results.losses[i], 3)} kVA"
)
print()
equal = True
for i in range(len(approx_volt)):
if approx_volt[i] != solution[i]:
equal = False
assert equal
def test_xfo_static_tap_1():
"""
Basic test with the main transformer's HV tap (X_C3) set at +5% (1.05 pu),
which lowers the LV by the same amount (-5%).
"""
test_name = "test_xfo_static_tap_1"
grid = MultiCircuit(name=test_name)
grid.Sbase = Sbase
grid.time_profile = None
grid.logger = Logger()
# Create buses
POI = Bus(
name="POI",
vnom=100, #kV
is_slack=True)
grid.add_bus(POI)
B_C3 = Bus(name="B_C3", vnom=10) #kV
grid.add_bus(B_C3)
B_MV_M32 = Bus(name="B_MV_M32", vnom=10) #kV
grid.add_bus(B_MV_M32)
B_LV_M32 = Bus(name="B_LV_M32", vnom=0.6) #kV
grid.add_bus(B_LV_M32)
# Create voltage controlled generators (or slack, a.k.a. swing)
UT = Generator(name="Utility")
UT.bus = POI
grid.add_generator(POI, UT)
# Create static generators (with fixed power factor)
M32 = StaticGenerator(name="M32", P=4.2, Q=0.0) # MVA (complex)
M32.bus = B_LV_M32
grid.add_static_generator(B_LV_M32, M32)
# Create transformer types
s = 5 # MVA
z = 8 # %
xr = 40
SS = TransformerType(
name="SS",
hv_nominal_voltage=100, # kV
lv_nominal_voltage=10, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(SS)
s = 5 # MVA
z = 6 # %
xr = 20
PM = TransformerType(
name="PM",
hv_nominal_voltage=10, # kV
lv_nominal_voltage=0.6, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(PM)
# Create branches
X_C3 = Branch(bus_from=POI,
bus_to=B_C3,
name="X_C3",
branch_type=BranchType.Transformer,
template=SS,
tap=1.05)
grid.add_branch(X_C3)
C_M32 = Branch(bus_from=B_C3,
bus_to=B_MV_M32,
name="C_M32",
r=0.784,
x=0.174)
grid.add_branch(C_M32)
X_M32 = Branch(bus_from=B_MV_M32,
bus_to=B_LV_M32,
name="X_M32",
branch_type=BranchType.Transformer,
template=PM)
grid.add_branch(X_M32)
# Apply templates (device types)
grid.apply_all_branch_types()
print("Buses:")
for i, b in enumerate(grid.buses):
print(f" - bus[{i}]: {b}")
print()
options = PowerFlowOptions(SolverType.NR,
verbose=True,
initialize_with_existing_solution=True,
multi_core=True,
control_q=ReactivePowerControlMode.Direct,
tolerance=1e-6,
max_iter=99)
power_flow = PowerFlowDriver(grid, options)
power_flow.run()
approx_volt = [round(100 * abs(v), 1) for v in power_flow.results.voltage]
solution = [100.0, 94.7, 98.0, 98.1] # Expected solution from GridCal
print()
print(f"Test: {test_name}")
print(f"Results: {approx_volt}")
print(f"Solution: {solution}")
print()
print("Generators:")
for g in grid.get_generators():
print(f" - Generator {g}: q_min={g.Qmin} MVAR, q_max={g.Qmax} MVAR")
print()
print("Branches:")
for b in grid.branches:
print(f" - {b}:")
print(f" R = {round(b.R, 4)} pu")
print(f" X = {round(b.X, 4)} pu")
print(f" X/R = {round(b.X/b.R, 1)}")
print(f" G = {round(b.G, 4)} pu")
print(f" B = {round(b.B, 4)} pu")
print()
print("Transformer types:")
for t in grid.transformer_types:
print(
f" - {t}: Copper losses={int(t.Pcu)}kW, Iron losses={int(t.Pfe)}kW, SC voltage={t.Vsc}%"
)
print()
print("Losses:")
for i in range(len(grid.branches)):
print(
f" - {grid.branches[i]}: losses={1000*round(power_flow.results.losses[i], 3)} kVA"
)
print()
equal = True
for i in range(len(approx_volt)):
if approx_volt[i] != solution[i]:
equal = False
assert equal
def test_xfo_static_tap_3():
"""
Basic test with the main transformer's HV tap (X_C3) set at -2.5%
(0.975 pu), which raises the LV by the same amount (+2.5%).
"""
test_name = "test_xfo_static_tap_3"
grid = MultiCircuit(name=test_name)
grid.Sbase = Sbase
grid.time_profile = None
grid.logger = Logger()
# Create buses
POI = Bus(
name="POI",
vnom=100, # kV
is_slack=True)
grid.add_bus(POI)
B_C3 = Bus(name="B_C3", vnom=10) # kV
grid.add_bus(B_C3)
B_MV_M32 = Bus(name="B_MV_M32", vnom=10) # kV
grid.add_bus(B_MV_M32)
B_LV_M32 = Bus(name="B_LV_M32", vnom=0.6) # kV
grid.add_bus(B_LV_M32)
# Create voltage controlled generators (or slack, a.k.a. swing)
UT = Generator(name="Utility")
UT.bus = POI
grid.add_generator(POI, UT)
# Create static generators (with fixed power factor)
M32 = StaticGenerator(name="M32", P=4.2, Q=0.0) # MVA (complex)
M32.bus = B_LV_M32
grid.add_static_generator(B_LV_M32, M32)
# Create transformer types
s = 5 # MVA
z = 8 # %
xr = 40
SS = TransformerType(
name="SS",
hv_nominal_voltage=100, # kV
lv_nominal_voltage=10, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(SS)
s = 5 # MVA
z = 6 # %
xr = 20
PM = TransformerType(
name="PM",
hv_nominal_voltage=10, # kV
lv_nominal_voltage=0.6, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(PM)
# Create branches
X_C3 = Branch(bus_from=POI,
bus_to=B_C3,
name="X_C3",
branch_type=BranchType.Transformer,
template=SS,
tap=0.975)
# update to a more precise tap changer
X_C3.apply_tap_changer(
TapChanger(taps_up=20, taps_down=20, max_reg=1.1, min_reg=0.9))
grid.add_branch(X_C3)
C_M32 = Branch(bus_from=B_C3,
bus_to=B_MV_M32,
name="C_M32",
r=0.784,
x=0.174)
grid.add_branch(C_M32)
X_M32 = Branch(bus_from=B_MV_M32,
bus_to=B_LV_M32,
name="X_M32",
branch_type=BranchType.Transformer,
template=PM)
grid.add_branch(X_M32)
# Apply templates (device types)
grid.apply_all_branch_types()
print("Buses:")
for i, b in enumerate(grid.buses):
print(f" - bus[{i}]: {b}")
print()
options = PowerFlowOptions(SolverType.NR,
verbose=True,
initialize_with_existing_solution=True,
multi_core=True,
control_q=ReactivePowerControlMode.Direct,
tolerance=1e-6,
max_iter=15)
power_flow = PowerFlowDriver(grid, options)
power_flow.run()
print()
print(f"Test: {test_name}")
print()
print("Generators:")
for g in grid.get_generators():
print(f" - Generator {g}: q_min={g.Qmin} MVAR, q_max={g.Qmax} MVAR")
print()
print("Branches:")
for b in grid.branches:
print(f" - {b}:")
print(f" R = {round(b.R, 4)} pu")
print(f" X = {round(b.X, 4)} pu")
print(f" X/R = {round(b.X/b.R, 1)}")
print(f" G = {round(b.G, 4)} pu")
print(f" B = {round(b.B, 4)} pu")
print()
print("Transformer types:")
for t in grid.transformer_types:
print(f" - {t}: Copper losses={int(t.Pcu)}kW, "
f"Iron losses={int(t.Pfe)}kW, SC voltage={t.Vsc}%")
print()
print("Losses:")
for i in range(len(grid.branches)):
print(
f" - {grid.branches[i]}: losses={1000*round(power_flow.results.losses[i], 3)} kVA"
)
print()
equal = False
for i, branch in enumerate(grid.branches):
if branch.name == "X_C3":
equal = power_flow.results.tap_module[i] == branch.tap_module
if not equal:
grid.export_pf(f"{test_name}_results.xlsx", power_flow.results)
grid.save_excel(f"{test_name}_grid.xlsx")
assert equal
def test_gridcal_regulator():
"""
GridCal test for the new implementation of transformer voltage regulators.
"""
test_name = "test_gridcal_regulator"
grid = MultiCircuit(name=test_name)
grid.Sbase = 100.0 # MVA
grid.time_profile = None
grid.logger = Logger()
# Create buses
POI = Bus(
name="POI",
vnom=100, # kV
is_slack=True)
grid.add_bus(POI)
B_C3 = Bus(name="B_C3", vnom=10) # kV
grid.add_bus(B_C3)
B_MV_M32 = Bus(name="B_MV_M32", vnom=10) # kV
grid.add_bus(B_MV_M32)
B_LV_M32 = Bus(name="B_LV_M32", vnom=0.6) # kV
grid.add_bus(B_LV_M32)
# Create voltage controlled generators (or slack, a.k.a. swing)
UT = Generator(name="Utility")
UT.bus = POI
grid.add_generator(POI, UT)
# Create static generators (with fixed power factor)
M32 = StaticGenerator(name="M32", P=4.2, Q=0.0) # MVA (complex)
M32.bus = B_LV_M32
grid.add_static_generator(B_LV_M32, M32)
# Create transformer types
s = 100 # MVA
z = 8 # %
xr = 40
SS = TransformerType(
name="SS",
hv_nominal_voltage=100, # kV
lv_nominal_voltage=10, # kV
nominal_power=s, # MVA
copper_losses=complex_impedance(z, xr).real * s * 1000.0 /
grid.Sbase, # kW
iron_losses=125, # kW
no_load_current=0.5, # %
short_circuit_voltage=z) # %
grid.add_transformer_type(SS)
s = 5 # MVA
z = 6 # %
xr = 20
PM = TransformerType(
name="PM",
hv_nominal_voltage=10, # kV
lv_nominal_voltage=0.6, # kV
nominal_power=s, # MVA
copper_losses=complex_impedance(z, xr).real * s * 1000.0 /
grid.Sbase, # kW
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z) # %
grid.add_transformer_type(PM)
# Create branches
X_C3 = Branch(bus_from=POI,
bus_to=B_C3,
name="X_C3",
branch_type=BranchType.Transformer,
template=SS,
bus_to_regulated=True,
vset=1.05)
X_C3.tap_changer = TapChanger(taps_up=16,
taps_down=16,
max_reg=1.1,
min_reg=0.9)
X_C3.tap_changer.set_tap(X_C3.tap_module)
grid.add_branch(X_C3)
C_M32 = Branch(bus_from=B_C3,
bus_to=B_MV_M32,
name="C_M32",
r=7.84,
x=1.74)
grid.add_branch(C_M32)
X_M32 = Branch(bus_from=B_MV_M32,
bus_to=B_LV_M32,
name="X_M32",
branch_type=BranchType.Transformer,
template=PM)
grid.add_branch(X_M32)
# Apply templates (device types)
grid.apply_all_branch_types()
print("Buses:")
for i, b in enumerate(grid.buses):
print(f" - bus[{i}]: {b}")
print()
options = PowerFlowOptions(SolverType.NR,
verbose=True,
initialize_with_existing_solution=True,
multi_core=True,
control_q=ReactivePowerControlMode.Direct,
control_taps=TapsControlMode.Direct,
tolerance=1e-6,
max_iter=99)
power_flow = PowerFlowDriver(grid, options)
power_flow.run()
approx_volt = [round(100 * abs(v), 1) for v in power_flow.results.voltage]
solution = [100.0, 105.2, 130.0, 130.1] # Expected solution from GridCal
print()
print(f"Test: {test_name}")
print(f"Results: {approx_volt}")
print(f"Solution: {solution}")
print()
print("Generators:")
for g in grid.get_generators():
print(f" - Generator {g}: q_min={g.Qmin}pu, q_max={g.Qmax}pu")
print()
print("Branches:")
branches = grid.get_branches()
for b in grid.transformers2w:
print(
f" - {b}: R={round(b.R, 4)}pu, X={round(b.X, 4)}pu, X/R={round(b.X/b.R, 1)}, vset={b.vset}"
)
print()
print("Transformer types:")
for t in grid.transformer_types:
print(
f" - {t}: Copper losses={int(t.Pcu)}kW, Iron losses={int(t.Pfe)}kW, SC voltage={t.Vsc}%"
)
print()
print("Losses:")
for i in range(len(branches)):
print(
f" - {branches[i]}: losses={round(power_flow.results.losses[i], 3)} MVA"
)
print()
tr_vset = [tr.vset for tr in grid.transformers2w]
print(f"Voltage settings: {tr_vset}")
equal = np.isclose(approx_volt, solution, atol=1e-3).all()
assert equal
def test_pv_3():
"""
Voltage controlled generator test, also useful for a basic tutorial. In this
case the generator M32 regulates the voltage at a setpoint of 1.025 pu, and
the slack bus (POI) regulates it at 1.0 pu.
The transformers' magnetizing branch losses are considered, as well as the
main power transformer's voltage regulator (X_C3) which regulates bus
B_MV_M32 at 1.005 pu.
In addition, the iterative PV control method is used instead of the usual
(faster) method.
"""
test_name = "test_pv_3"
grid = MultiCircuit(name=test_name)
Sbase = 100 # MVA
grid.Sbase = Sbase
grid.time_profile = None
grid.logger = Logger()
# Create buses
POI = Bus(
name="POI",
vnom=100, # kV
is_slack=True)
grid.add_bus(POI)
B_MV_M32 = Bus(name="B_MV_M32", vnom=10) # kV
grid.add_bus(B_MV_M32)
B_LV_M32 = Bus(name="B_LV_M32", vnom=0.6) # kV
grid.add_bus(B_LV_M32)
# Create voltage controlled generators (or slack, a.k.a. swing)
UT = Generator(name="Utility")
UT.bus = POI
grid.add_generator(POI, UT)
M32 = Generator(name="M32",
active_power=4.2,
voltage_module=1.025,
Qmin=-2.5,
Qmax=2.5)
M32.bus = B_LV_M32
grid.add_generator(B_LV_M32, M32)
# Create transformer types
s = 100 # MVA
z = 8 # %
xr = 40
SS = TransformerType(
name="SS",
hv_nominal_voltage=100, # kV
lv_nominal_voltage=10, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=125, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(SS)
s = 5 # MVA
z = 6 # %
xr = 20
PM = TransformerType(
name="PM",
hv_nominal_voltage=10, # kV
lv_nominal_voltage=0.6, # kV
nominal_power=s,
copper_losses=complex_impedance(z, xr).real * s * 1000 / Sbase,
iron_losses=6.25, # kW
no_load_current=0.5, # %
short_circuit_voltage=z)
grid.add_transformer_type(PM)
# Create branches
X_C3 = Branch(bus_from=POI,
bus_to=B_MV_M32,
name="X_C3",
branch_type=BranchType.Transformer,
template=SS,
bus_to_regulated=True,
vset=1.005)
X_C3.tap_changer = TapChanger(taps_up=16,
taps_down=16,
max_reg=1.1,
min_reg=0.9)
X_C3.tap_changer.set_tap(X_C3.tap_module)
grid.add_branch(X_C3)
X_M32 = Branch(bus_from=B_MV_M32,
bus_to=B_LV_M32,
name="X_M32",
branch_type=BranchType.Transformer,
template=PM)
grid.add_branch(X_M32)
# Apply templates (device types)
grid.apply_all_branch_types()
print("Buses:")
for i, b in enumerate(grid.buses):
print(f" - bus[{i}]: {b}")
print()
options = PowerFlowOptions(SolverType.LM,
verbose=True,
initialize_with_existing_solution=True,
multi_core=True,
control_q=ReactivePowerControlMode.Iterative,
control_taps=TapsControlMode.Direct,
tolerance=1e-6,
max_iter=99)
power_flow = PowerFlowDriver(grid, options)
power_flow.run()
approx_volt = [round(100 * abs(v), 1) for v in power_flow.results.voltage]
solution = [100.0, 100.7, 102.5] # Expected solution from GridCal
print()
print(f"Test: {test_name}")
print(f"Results: {approx_volt}")
print(f"Solution: {solution}")
print()
print("Generators:")
for g in grid.get_generators():
print(f" - Generator {g}: q_min={g.Qmin} MVAR, q_max={g.Qmax} MVAR")
print()
print("Branches:")
for b in grid.branches:
print(f" - {b}:")
print(f" R = {round(b.R, 4)} pu")
print(f" X = {round(b.X, 4)} pu")
print(f" X/R = {round(b.X / b.R, 1)}")
print(f" G = {round(b.G, 4)} pu")
print(f" B = {round(b.B, 4)} pu")
print()
print("Transformer types:")
for t in grid.transformer_types:
print(
f" - {t}: Copper losses={int(t.Pcu)}kW, Iron losses={int(t.Pfe)}kW, SC voltage={t.Vsc}%"
)
print()
print("Losses:")
for i in range(len(grid.branches)):
print(
f" - {grid.branches[i]}: losses={1000 * round(power_flow.results.losses[i], 3)} kVA"
)
print()
equal = True
for i in range(len(approx_volt)):
if approx_volt[i] != solution[i]:
equal = False
assert equal
def test_transformer_definition():
Vf = 20.0 # kV
Vt = 0.4 # kV
Sn = 0.5 # MVA
Vsc_ = 6.0 # %
Pcu_ = 6.0 # kW
# Pfe_ = 1.4 # kW
# I0_ = 0.28 # %
Pfe_ = 0.0 # kW
I0_ = 0.0 # %
tpe = TransformerType(hv_nominal_voltage=Vf,
lv_nominal_voltage=Vt,
nominal_power=Sn,
copper_losses=Pcu_,
iron_losses=Pfe_,
no_load_current=I0_,
short_circuit_voltage=Vsc_,
gr_hv1=0.5,
gx_hv1=0.5)
z, zl = tpe.get_impedances()
print(z)
print(zl)
# ------------------------------------------------------------------------------------------------------------------
# Revert the calcs
# ------------------------------------------------------------------------------------------------------------------
if zl.real > 0 and zl.imag > 0:
yl = 1.0 / zl
G = yl.real
B = yl.imag
else:
G = 0
B = 0
R = z.real
X = z.imag
Sn = Sn
print()
print('R', R)
print('X', X)
print('G', G)
print('B', B)
zsc = sqrt(R * R + 1 / (X * X))
Vsc = 100.0 * zsc
Pcu = R * Sn * 1000.0
if abs(G) > 0.0 and abs(B) > 0.0:
zl = 1.0 / complex(G, B)
rfe = zl.real
xm = zl.imag
Pfe = 1000.0 * Sn / rfe
k = 1 / (rfe * rfe) + 1 / (xm * xm)
I0 = 100.0 * sqrt(k)
else:
Pfe = 1e20
I0 = 1e20
print('Vsc', Vsc, Vsc_)
print('Pcu', Pcu, Pcu_)
print('I0', I0, I0_)
print('Pfe', Pfe, Pfe_)
tpe2 = TransformerType(hv_nominal_voltage=Vf,
lv_nominal_voltage=Vt,
nominal_power=Sn,
copper_losses=Pcu,
iron_losses=Pfe,
no_load_current=I0,
short_circuit_voltage=Vsc,
gr_hv1=0.5,
gx_hv1=0.5)
z2, zl2 = tpe2.get_impedances()
print(z2)
print(zl2)
