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Transformer leakage inductance calculation in Maxwell 2D Magnetostatic#
This example shows how you can use pyAEDT to create a Maxwell 2D magnetostatic analysis to calculate transformer leakage inductance and reactance. The analysis based on this document form page 8 on: https://www.ee.iitb.ac.in/~fclab/FEM/FEM1.pdf
Perform required imports#
import tempfile
from ansys.aedt.core import Maxwell2d
temp_dir = tempfile.TemporaryDirectory(suffix=".ansys")
- Initialize and launch Maxwell 2D
Initialize and launch Maxwell 2D, providing the version, path to the project, and the design name and type.
non_graphical = False
project_name = "Transformer_leakage_inductance"
design_name = "1 Magnetostatic"
solver = "MagnetostaticXY"
desktop_version = "2024.2"
m2d = Maxwell2d(version=desktop_version,
new_desktop=False,
design=design_name,
project=project_name,
solution_type=solver,
non_graphical=non_graphical)
C:\actions-runner\_work\_tool\Python\3.10.9\x64\lib\subprocess.py:1072: ResourceWarning: subprocess 700 is still running
_warn("subprocess %s is still running" % self.pid,
C:\actions-runner\_work\pyaedt\pyaedt\.venv\lib\site-packages\ansys\aedt\core\generic\settings.py:231: ResourceWarning: unclosed file <_io.TextIOWrapper name='D:\\Temp\\pyaedt_ansys_0bf9f20b-53ab-4ce4-97b2-0987472c9727.log' mode='a' encoding='cp1252'>
self.__logger = val
Initialize dictionaries#
Initialize dictionaries that contain all the definitions for the design variables.
mod = m2d.modeler
mod.model_units = "mm"
dimensions = {
"core_width": "1097mm",
"core_height": "2880mm",
"core_opening_x1": "270mm",
"core_opening_x2": "557mm",
"core_opening_y1": "540mm",
"core_opening_y2": "2340mm",
"core_opening_width": "core_opening_x2-core_opening_x1",
"core_opening_height": "core_opening_y2-core_opening_y1",
"LV_x1": "293mm",
"LV_x2": "345mm",
"LV_width": "LV_x2-LV_x1",
"LV_mean_radius": "LV_x1+LV_width/2",
"LV_mean_turn_length": "pi*2*LV_mean_radius",
"LV_y1": "620mm",
"LV_y2": "2140mm",
"LV_height": "LV_y2-LV_y1",
"HV_x1": "394mm",
"HV_x2": "459mm",
"HV_width": "HV_x2-HV_x1",
"HV_mean_radius": "HV_x1+HV_width/2",
"HV_mean_turn_length": "pi*2*HV_mean_radius",
"HV_y1": "620mm",
"HV_y2": "2140mm",
"HV_height": "HV_y2-HV_y1",
"HV_LV_gap_radius": "(LV_x2 + HV_x1)/2",
"HV_LV_gap_length": "pi*2*HV_LV_gap_radius",
}
specifications = {
"Amp_turns": "135024A",
"Frequency": "50Hz",
"HV_turns": "980",
"HV_current": "Amp_turns/HV_turns",
}
Define variables from dictionaries#
Define design variables from the created dictionaries.
m2d.variable_manager.set_variable(name="Dimensions")
for k, v in dimensions.items():
m2d[k] = v
m2d.variable_manager.set_variable(name="Windings")
for k, v in specifications.items():
m2d[k] = v
Create design geometries#
Create transformer core, HV and LV windings, and the region.
core_id = mod.create_rectangle(
position=[0, 0, 0],
dimension_list=["core_width", "core_height", 0],
name="core",
matname="steel_1008",
)
core_hole_id = mod.create_rectangle(
position=["core_opening_x1", "core_opening_y1", 0],
dimension_list=["core_opening_width", "core_opening_height", 0],
name="core_hole",
)
mod.subtract(blank_list=[core_id], tool_list=[core_hole_id], keep_originals=False)
lv_id = mod.create_rectangle(
position=["LV_x1", "LV_y1", 0],
dimension_list=["LV_width", "LV_height", 0],
name="LV",
matname="copper",
)
hv_id = mod.create_rectangle(
position=["HV_x1", "HV_y1", 0],
dimension_list=["HV_width", "HV_height", 0],
name="HV",
matname="copper",
)
# Very small region is enough, because all the flux is concentrated in the core
region_id = mod.create_region(
pad_percent=[20, 10, 0, 10]
)
Assign boundary condition#
Assign vector potential to zero on all region boundaries. This makes x=0 edge a symmetry boundary.
region_edges = region_id.edges
m2d.assign_vector_potential(
input_edge=region_edges,
bound_name="VectorPotential1"
)
<ansys.aedt.core.modules.boundary.BoundaryObject object at 0x0000020CDAABFF70>
Create initial mesh settings#
Assign a relatively dense mesh to all objects to ensure that the energy is calculated accurately.
m2d.mesh.assign_length_mesh(
names=["core", "Region", "LV", "HV"],
maxlength=50,
maxel=None,
meshop_name="all_objects"
)
<ansys.aedt.core.modules.mesh.MeshOperation object at 0x0000020CDB32BBB0>
Define excitations#
Assign the same current in amp-turns but in opposite directions to HV and LV windings.
m2d.assign_current(
object_list=lv_id,
amplitude="Amp_turns",
name="LV"
)
m2d.assign_current(
object_list=hv_id,
amplitude="Amp_turns",
name="HV",
swap_direction=True
)
<ansys.aedt.core.modules.boundary.BoundaryObject object at 0x0000020CD84C0F10>
Create and analyze the setup#
Create and analyze the setup. Setu no. of minimum passes to 3 to ensure accuracy.
m2d.create_setup(
setupname="Setup1",
MinimumPasses=3
)
m2d.analyze_setup()
True
Calculate transformer leakage inductance and reactance#
Calculate transformer leakage inductance from the magnetic energy.
field_calculator = m2d.ofieldsreporter
field_calculator.EnterQty("Energy")
field_calculator.EnterSurf("HV")
field_calculator.CalcOp("Integrate")
field_calculator.EnterScalarFunc("HV_mean_turn_length")
field_calculator.CalcOp("*")
field_calculator.EnterQty("Energy")
field_calculator.EnterSurf("LV")
field_calculator.CalcOp("Integrate")
field_calculator.EnterScalarFunc("LV_mean_turn_length")
field_calculator.CalcOp("*")
field_calculator.EnterQty("Energy")
field_calculator.EnterSurf("Region")
field_calculator.CalcOp("Integrate")
field_calculator.EnterScalarFunc("HV_LV_gap_length")
field_calculator.CalcOp("*")
field_calculator.CalcOp("+")
field_calculator.CalcOp("+")
field_calculator.EnterScalar(2)
field_calculator.CalcOp("*")
field_calculator.EnterScalarFunc("HV_current")
field_calculator.EnterScalarFunc("HV_current")
field_calculator.CalcOp("*")
field_calculator.CalcOp("/")
field_calculator.AddNamedExpression("Leakage_inductance", "Fields")
field_calculator.CopyNamedExprToStack("Leakage_inductance")
field_calculator.EnterScalar(2)
field_calculator.EnterScalar(3.14159265358979)
field_calculator.EnterScalarFunc("Frequency")
field_calculator.CalcOp("*")
field_calculator.CalcOp("*")
field_calculator.CalcOp("*")
field_calculator.AddNamedExpression("Leakage_reactance", "Fields")
m2d.post.create_report(
expressions=["Leakage_inductance", "Leakage_reactance"],
report_category="Fields",
primary_sweep_variable="core_width",
plot_type="Data Table",
plotname="Transformer Leakage Inductance",
)
<ansys.aedt.core.modules.report_templates.Fields object at 0x0000020CD6ED5510>
Print leakage inductance and reactance values in the Message Manager#
Print leakage inductance and reactance values in the Message Manager
m2d.logger.clear_messages()
m2d.logger.info(
"Leakage_inductance = {:.4f}H".format(m2d.post.get_scalar_field_value(quantity_name="Leakage_inductance"))
)
m2d.logger.info(
"Leakage_reactance = {:.2f}Ohm".format(m2d.post.get_scalar_field_value(quantity_name="Leakage_reactance"))
)
Plot energy in the simulation domain#
Most of the energy is confined in the air between the HV and LV windings.
object_faces = []
for name in mod.object_names:
object_faces.extend(m2d.modeler.get_object_faces(name))
energy_field_overlay = m2d.post.create_fieldplot_surface(
objlist=object_faces,
quantityName="energy",
plot_name="Energy",
)
m2d.save_project()
m2d.release_desktop()
temp_dir.cleanup()
Total running time of the script: (1 minutes 29.878 seconds)