from numpy import zeros, ones, dot, squeeze
from SciDataTool import DataTime
from ....Classes.OPdq import OPdq
from ....Functions.Electrical.dqh_transformation import dqh2n
from ....Functions.Load.import_class import import_class
from ....Methods.Simulation.Input import CURRENT_DIR_REF, PHASE_DIR_REF, ROT_DIR_REF
[docs]def comp_mmf_unit(self, Na=None, Nt=None, felec=1, current_dir=None, phase_dir=None):
"""Compute the winding unit magnetomotive force for given inputs
Parameters
----------
self : LamSlotWind
an LamSlotWind object
Na : int
Space discretization for offline computation
Nt : int
Time discretization for offline computation
felec : float
Stator current frequency to consider
current_dir: int
Stator current rotation direction +/-1
phase_dir: int
Stator winding phasor rotation direction +/-1
Returns
-------
MMF_U : DataTime
Unit magnetomotive force (Na,Nt)
WF : DataTime
Winding functions (qs,Na)
"""
# Check that parent machine is not None
if self.parent is None:
raise Exception("Cannot calculate mmf unit if parent machine is None")
else:
machine = self.parent
# Compute the winding function and mmf
if self.winding is None:
raise Exception("Cannot calculate mmf unit if winding is None")
else:
# Get stator winding number of phases
qs = self.winding.qs
if current_dir is None:
current_dir = CURRENT_DIR_REF
elif current_dir not in [-1, 1]:
raise Exception("Cannot enforce current_dir other than +1 or -1")
if phase_dir is None:
phase_dir = PHASE_DIR_REF
elif phase_dir not in [-1, 1]:
raise Exception("Cannot enforce phase_dir other than +1 or -1")
InputVoltage = import_class("pyleecan.Classes", "InputVoltage")
input = InputVoltage(
Na_tot=Na,
Nt_tot=Nt,
OP=OPdq(felec=felec),
current_dir=current_dir,
rot_dir=ROT_DIR_REF, # rotor rotating dir has not impact on unit mmf
)
axes_dict = input.comp_axes(
axes_list=["time", "angle", "phase_S", "phase_R"],
machine=machine,
is_periodicity_t=bool(Nt > 1),
is_periodicity_a=bool(Na > 1),
is_antiper_t=False,
is_antiper_a=False,
)
# Compute winding function
angle = axes_dict["angle"].get_values(is_oneperiod=True)
per_a, _ = axes_dict["angle"].get_periodicity()
wf = self.comp_wind_function(angle=angle, per_a=per_a)
# Compute unit current function of time applying constant Id=1 Arms, Iq=Ih=0
angle_elec = axes_dict["time"].get_values(
is_oneperiod=True, normalization="angle_elec"
)
Idq = zeros((angle_elec.size, 3))
Idq[:, 0] = ones(angle_elec.size)
I = dqh2n(Idq, angle_elec, n=qs, is_n_rms=False, phase_dir=phase_dir)
# Compute unit mmf
mmf_u = squeeze(dot(I, wf))
# Create a Data object
MMF_U = DataTime(
name="Overall MMF",
unit="A",
symbol="MMF",
axes=[axes_dict["time"], axes_dict["angle"]],
values=mmf_u,
)
WF = DataTime(
name="Phase MMF",
unit="A",
symbol="MMF",
axes=[axes_dict["angle"], axes_dict["phase_" + self.get_label()]],
values=wf.T,
)
return MMF_U, WF
