-
Notifications
You must be signed in to change notification settings - Fork 11
/
basic_transformer_stacked.py
162 lines (136 loc) · 8.27 KB
/
basic_transformer_stacked.py
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
"""
Basic example to show how to simulate a stacked transformer.
After starting the program, the geometry dimensions are displayed. Verify this geometry, close the window, to continue the simulation.
After a short time, B-Field and winding losses simulation results are shown. Winding losses are shown as a colormap.
In the core, the magnitude B-Field in Tesla is shown. With the gmsh window, one can move the picture in the 3D way (not recommended).
If you close this window, the thermal simulation will be continued, if programmed. If true, the thermal heat distribution will be displayed.
To continue with the next simulation (or end the program), you need to close this window. All results are written to the result
folder .../femmt/examples/example_results/simulation_file_name/results/log_electro_magnetic.json. and .../results_thermal.json.
"""
import femmt as fmt
import os
def basic_example_transformer_stacked(onelab_folder: str = None, show_visual_outputs: bool = True,
is_test: bool = False):
"""
Run the example code for the stacked transformer.
:param onelab_folder: onelab folder path
:type onelab_folder: str
:param show_visual_outputs: True to show visual outputs (simulation results)
:type show_visual_outputs: bool
:param is_test: True for pytest usage. Defaults to False.
:type is_test: bool
"""
def example_thermal_simulation(show_thermal_visual_outputs: bool = True, flag_insulation: bool = True):
# Thermal simulation:
# The losses calculated by the magnetics simulation can be used to calculate the heat distribution of the
# given magnetic component. In order to use the thermal simulation, thermal conductivities for each material
# can be entered as well as a boundary temperature which will be applied on the boundary of the
# simulation (dirichlet boundary condition).
# The case parameter sets the thermal conductivity for a case which will be set around the core.
# This could model some case in which the transformer is placed in together with a set potting material.
thermal_conductivity_dict = {
"air": 0.0263,
"case": { # epoxy resign
"top": 1.54,
"top_right": 1.54,
"right": 1.54,
"bot_right": 1.54,
"bot": 1.54
},
"core": 5, # ferrite
"winding": 400, # copper
"air_gaps": 180, # aluminium nitride
"insulation": 0.42 if flag_insulation else None # polyethylene
}
# Here the case size can be determined
case_gap_top = 0.002
case_gap_right = 0.0025
case_gap_bot = 0.002
# Here the boundary temperatures can be set, currently it is set to 20°C (around 293°K).
# This does not change the results of the simulation (at least when every boundary is set equally)
# but will set the temperature offset.
boundary_temperatures = {
"value_boundary_top": 20,
"value_boundary_top_right": 20,
"value_boundary_right_top": 20,
"value_boundary_right": 20,
"value_boundary_right_bottom": 20,
"value_boundary_bottom_right": 20,
"value_boundary_bottom": 20
}
# Here the boundary sides can be turned on (1) or off (0)
# By turning off the flag a neumann boundary will be applied at this point with heat flux = 0
boundary_flags = {
"flag_boundary_top": 0,
"flag_boundary_top_right": 0,
"flag_boundary_right_top": 1,
"flag_boundary_right": 1,
"flag_boundary_right_bottom": 1,
"flag_boundary_bottom_right": 1,
"flag_boundary_bottom": 1
}
# In order for the thermal simulation to work an electro_magnetic simulation has to run before.
# The em-simulation will create a file containing the losses.
# When the losses file is already created and contains the losses for the current model, it is enough to
# run geo.create_model in order for the thermal simulation to work (geo.single_simulation is not needed).
# Obviously when the model is modified and the losses can be out of date and therefore the
# geo.single_simulation needs to run again.
geo.thermal_simulation(thermal_conductivity_dict, boundary_temperatures, boundary_flags, case_gap_top,
case_gap_right, case_gap_bot, show_thermal_visual_outputs,
color_scheme=fmt.colors_ba_jonas, colors_geometry=fmt.colors_geometry_ba_jonas,
flag_insulation=flag_insulation)
example_results_folder = os.path.join(os.path.dirname(__file__), "example_results")
if not os.path.exists(example_results_folder):
os.mkdir(example_results_folder)
working_directory = os.path.join(example_results_folder, os.path.splitext(os.path.basename(__file__))[0])
if not os.path.exists(working_directory):
os.mkdir(working_directory)
# 1. chose simulation type
geo = fmt.MagneticComponent(component_type=fmt.ComponentType.IntegratedTransformer,
working_directory=working_directory, verbosity=fmt.Verbosity.ToConsole, is_gui=is_test)
# This line is for automated pytest running on GitHub only. Please ignore this line!
if onelab_folder is not None:
geo.file_data.onelab_folder_path = onelab_folder
# 2. set core parameters
core_dimensions = fmt.dtos.StackedCoreDimensions(core_inner_diameter=0.02, window_w=0.02, window_h_top=0.01,
window_h_bot=0.03)
core = fmt.Core(core_type=fmt.CoreType.Stacked, core_dimensions=core_dimensions, mu_r_abs=3100, phi_mu_deg=12,
sigma=0.6,
permeability_datasource=fmt.MaterialDataSource.Custom,
permittivity_datasource=fmt.MaterialDataSource.Custom)
geo.set_core(core)
# 3. set air gap parameters
air_gaps = fmt.AirGaps(fmt.AirGapMethod.Stacked, core)
air_gaps.add_air_gap(fmt.AirGapLegPosition.CenterLeg, 0.002, stacked_position=fmt.StackedPosition.Top)
air_gaps.add_air_gap(fmt.AirGapLegPosition.CenterLeg, 0.001, stacked_position=fmt.StackedPosition.Bot)
geo.set_air_gaps(air_gaps)
# 4. set insulations
insulation = fmt.Insulation(flag_insulation=False)
insulation.add_core_insulations(0.001, 0.001, 0.001, 0.001) # [bot, top, left, right]
insulation.add_winding_insulations([[0.0002, 0.001],
[0.001, 0.0002]])
geo.set_insulation(insulation)
winding_window_top, winding_window_bot = fmt.create_stacked_winding_windows(core, insulation)
vww_top = winding_window_top.split_window(fmt.WindingWindowSplit.NoSplit)
vww_bot = winding_window_bot.split_window(fmt.WindingWindowSplit.NoSplit)
# 6. set conductor parameters
winding1 = fmt.Conductor(0, fmt.Conductivity.Copper)
winding1.set_litz_round_conductor(None, 100, 70e-6, 0.5, fmt.ConductorArrangement.Square)
winding2 = fmt.Conductor(1, fmt.Conductivity.Copper)
winding2.set_solid_round_conductor(1e-3, fmt.ConductorArrangement.Square)
# winding2.set_litz_round_conductor(None, 120, 70e-6, 0.5, fmt.ConductorArrangement.Square)
# 7. add conductor to vww and add winding window to MagneticComponent
vww_top.set_interleaved_winding(winding1, 16, winding2, 0, fmt.InterleavedWindingScheme.HorizontalAlternating)
vww_bot.set_interleaved_winding(winding1, 40, winding2, 20, fmt.InterleavedWindingScheme.HorizontalAlternating)
geo.set_winding_windows([winding_window_top, winding_window_bot])
# 8. start simulation with given frequency, currents and phases
geo.create_model(freq=250000, pre_visualize_geometry=show_visual_outputs)
geo.single_simulation(freq=250000, current=[2.0, 4.0], phi_deg=[0, 180],
show_fem_simulation_results=show_visual_outputs)
# other simulation options:
# -------------------------
# geo.get_inductances(I0=10, op_frequency=100000, skin_mesh_factor=0.5)
# 7. prepare and start thermal simulation
example_thermal_simulation(show_visual_outputs, flag_insulation=False)
if __name__ == "__main__":
basic_example_transformer_stacked(show_visual_outputs=True)