Model and machine parameters¶
Basic parameters¶
Command: pre_models(“polzahl”)
Warning
This command will be replaced by run_models(“basic_modpar”) and will be omitted in future FEMAG releases.
Command: pre_models(“basic_modpar”)
Define the basic model parameters stored in the model files (A7/I7 and AUX7/ISA7) respectively.
Example and parameter description:
m.tot_num_slot = 12 -- Numer of slots
m.num_slots = 6 -- Number of slots in model
m.num_poles = 10 -- Number of poles 2p (>= 2)
m.npols_gen = 5 -- Number of poles simulated (>= 1)
m.arm_length = 100 -- Effect. armature length [mm]
m.fc_radius = 27 -- Radius air-gap center [mm]
pre_models("basic_modpar")
The m. parameters are optional: it is sufficient to specify the required parameters. For the parameter-based models (M-Models) available in FEMAG, these values are set automatically. To work with these optional parameter see Handling of global variables and optional parameters.
Material parameter¶
Command: pre_models(“FE-Losses-1”)
Determination of iron-loss parameters and parameters for mechanical and thermal simulation of the outer part of the model (i.e. the stator for inner-rotor machines).
Example and parameter description:
m.basfreq = 50.000 -- Base Frequency for ch and cw fo [Hz]
m.basind = 1.500 -- Base Induction (Peak) Bo [T]
m.ch = 4.000 -- Fe-Hysteresis -Coefficient ch [W/kg]
m.cw = 2.000 -- Fe-Eddy current-Coefficient cw [W/kg]
m.hyscoef = 1.000 -- Hysteresis- Frequency-Coefficient
m.edycoef = 2.000 -- Eddycurrent-Frequency-Coefficient
m.indcoef = 2.000 -- Induction-Coefficient
m.ffactor = 1.000 -- Material + Field Factor >= 1
m.spweight = 7.650 -- Specific Weight Iron [gr/cm3]
m.fillfact = 1.000 -- Fillfactor Iron <= 1
m.emodul = 999999.000 -- E-Modul [kN/mm2]
m.poison = 0.300 -- Poissonvalue <= 1
m.dampfact = 0.000 -- Dampingfactor
m.thcond = 0.000 -- Thermal conductivity [W/m degr]
m.thcap = 0.000 -- Thermal heat capacity [Ws/g degr]
pre_models("FE-Losses-1")
The parameters of the inner part can be set in an equivalent way with pre_models(“FE-Losses-2”).
Command: pre_models(“CU-Losses-1”)
Determination of winding parameters and parameters for mechanical and thermal simulation of the outer part of the model (i.e., the stator for inner-rotor machines).
Example and parameter description:
m.cufilfact = 0.450 -- Conductor space filling-factor: <= 1
m.culength = 140.000 -- Rel. conductor length (c+e wdg) [
m.cuconduct = 56000000.000 -- Conductor conductivity 20 Dgr C [S/m]
m.numlayers = 1.000 -- Number of conductor layers > = 1
m.conheight = 0.000 -- Rectangular Conductor height [mm]
m.contemp = 20.000 -- Conductor Temperature [Degree C]
m.emodul = 210.000 -- E-Modul [kN/mm2]
m.poison = 0.300 -- Poissonvalue <= 1
m.dampfact = 0.000 -- Dampingfactor
m.thcond = 30.000 -- Thermal conductivity [W/m degr]
m.thcap = 480.000 -- Thermal heat capacity [Ws/g degr]
m.slot_indul = 1.000 -- Slot insulation [mm]
m.dia_wire = 0.000 -- Diameter single round wire [mm]
m.num_wire = 0.000 -- Number of single wires/conductor
pre_models("CU-Losses-1")
The parameters of the inner part can be set in an equivalent way with pre_models(“FE-Losses-2”).
Command: pre_models(“conduct-data”)
Determination of the parameters of the permanent magnets.
Example and parameter description:
m.conduct = 10000000.000 -- Conductors el. conductivity [1/Ohm m]
m.conrelperm = 100.000 -- Rel. Permeability muer
m.contemp = 20.000 -- Conductor Temperature [Degree C]
m.contecoef = 0.000 -- Temperature Coefficient [
m.spconweight = 7.600 -- Specific Weight Conductors [gr/cm3]
m.relconlength = 100.000 -- Relative conductor length (c+e wdg)[
pre_models("conduct-data")
Command: pre_models(“Magnet-data”)
Definition of general permanent magnet properties.
Example and parameter description:
m.remanenc = 1.200 -- Remanence Br (Ref: 20 Degree C) [T]
m.relperm = 1.050 -- Relative permeability muer [-]
m.spmaweight = 7.600 -- Specific weight of magnets [gr/cm3]
m.temcoefbr = -0.100 -- Temperature coefficient for Br [
m.temcoefhc = -0.100 -- Temperature coefficient for Hc [
m.magntemp = 20.000 -- Magnet temperature [Degree C]
m.magncond = 625000.000 -- Magnet el. conductivity [1/Ohm m]
m.magsegwid = 51.100 -- Magnet segment width [mm]
m.magseglen = 120.000 -- Magnet segment length z-direction [mm]
pre_models("Magnet-data")
All parameters are optional.
If m.remanenc, m.relperm or m.magncond are modified, the related elements and super-elements properties of all magnets currently existing are changed automatically. In example, the remanence of all magnets can be changed globally to 1.1 T by
m.remanenc = 1.1
pre_models("Magnet-data")
The magnetization distribution and orientation are maintained.
The Dimensions m.magsegwid and m.magseglen are used for magnet loss calculation of segmented permanent magnets within the post processing (B method). m.magseglen refers to the segments length of an axially segmented permanent magnet. If m.magseglen is chosen larger than the total magnet length, it will be limited automatically. Please see warnings in the log file outputed during the script execution. If one of these dimensions is not specified, it will be identified automatically based on magnet geometry.
See section Machine how to get access to current data of individual parameter. The current magnet segment length used for loss calculation can be obtained or set individually by e.g.
set_dev_data("magnseg_width",width)
width = get_dev_data("magnseg_width")
Refering to upper example, the remanence of all permanent magnets can be set to 1.1 T by
set_dev_data("magn_remanence",1.1)
Notes
The assignment of material properties should succeed the definition of the basic model parameters, see section Basic parameters.
Regarding handling of optional parameters see section Handling of global variables and optional parameters.
In case of modification of a property which takes influence on the magnetic field solution, current FE calculation results are reseted.