BchReader

The BchReader object holds the most important FEMAG results. It has following attributes which mostly correspond to the text sections in the file:

Attribute	Description
project	Name of model file
filename	Name of BCH file
date	calculation date
version	FEMAG version
nodes	number of nodes
elements	number of elements
quality	meshing quality
windings	Winding properties
current_angles	Current Angles from no-load test
flux	Flux observed
flux_fft	Fourier-Analysis of flux values
torque	Torque-Force values
torque_fft	Fourier-Analysis of torque values
linearForce	Force x and y values
linearForce_fft	Fourier-Analysis of force values
psidq	PSID-Psiq-Identification
psidq_ldq	PSID-Psiq-Identification (Ld, Lq)
machine	Machine data
lossPar	Control parameters for Loss calculation
magnet	Magnet data
airgapInduction	airgap induction
scData	Transient short circuit
dqPar	DQ-Parameter for open Winding Modell
ldq	Ld-Lq-Identification
losses	Losses in iron, magnets and conductors from Move-calc
demag	Demagnetisation
weights	Total weight and weight of iron, conductor and magnets
inertia	Inertia of stator and rotor
characteristics	Characteristics of Permanent-Magnet-Motors
powerSituation	Power situation (VZS)
leak_dist_wind	End Winding Leakage

Flux

• Flux: list of dictionaries for each winding

  Attribute	Description
  displ	position
  displunit	unit (mm, deg) of position values
  flux_k	flux
  voltage_dpsi	voltage dpsi/dt
  voltage_four	voltage (fourier transformation)
  current_k	current
  voltage_ir	voltage

• flux_fft: list of dictionaries for each winding

  Attribute	Description
  order	order of harmonic
  flux	flux amplitude
  flux_perc	flux amplitude percentage of base harmonic
  voltage	voltage amplitude
  voltage_perc	voltage amplitude percentage of base harmonic
  a	amplitude of sin term
  b	amplitide of cos term

Torque

• torque: list of dictionaries for each current and/or beta angle (No load, load current with beta=0 and load current with beta)

  Attribute	Description
  angle	Position
  current_1	Current
  force_x	Force in x-direction
  force_y	Force in y-direction
  t_idpsi	Torque with dq-parameters
  torque	Torque with Maxwell stress tensor
  ripple	Diff between max and min torque value

  Note

  the force values are valid for the simulated model segment only. The torque values are valid for the complete machine.

• torque_fft: list of dictionaries for each current and/or beta angle

  Attribute	Description
  order	order of harmonic list
  torque	Torque amplitude list
  torque_perc	Torque in percentage of first amplitude
  a	amplitude list of sin term
  b	amplitude list of cos term

Linear Force

• linearForce: list of dictionaries for each current and/or beta angle

  Attribute	Description
  displ	Position
  magnet_1	Current
  force_x	Force in x direction
  force_y	Force in y direction

• linearForce_fft: list of dictionaries for each current and/or beta angle in x- and y-direction

  Attribute	Description
  order	order of harmonic list
  force	Force amplitude list
  force_perc	Force in percentage of first amplitude
  a	amplitude list of sin term
  b	amplitude list of cos term

Psidq

Attribute	Description	Unit
iq	Iq current list (n)	A
id	Id current list (m)	A
psid	Psid matrix (n x m)	Vs
psiq	Psiq matrix (n x m)	Vs
torque	Torque matrix (n x m)	Nm
losses	dict of loss values

• losses

Attribute	Description	Unit
styoke	Losses of stator yoke (n x m)	W
stteeth	Losses of stator teeth (n x m)	W
rotor	Losses of rotor (n x m)	W
magnet	Losses of magnet (n x m)	W
styoke_hyst	Hyst. Losses of stator yoke (n x m)	W
styoke_eddy	Eddy Losses of stator yoke (n x m)	W
stteeth_hyst	Hyst. Losses of stator teeth (n x m)	W
stteeth_eddy	Eddy Losses of stator yoke (n x m)	W
rotor_hyst	Hyst. Losses of rotor (n x m)	W
rotor_eddy	Eddy Losses of rotor (n x m)	W
speed	Speed	1/s

Psidq Ldq

Attribute	Description	Unit
iq	Iq current list (n)	A
id	Id current list (m)	A
ld	Ld matrix (n x m)	H
lq	Lq matrix (n x m)	H
psim	Psim matrix (n x m)	Vs
psid	Psid matrix (n x m)	Vs
psiq	Psiq matrix (n x m)	Vs
torque	Torque matrix (n x m)	Nm

Ldq

Attribute	Description	Unit
i1	I1 current list (n)	A
beta	Beta current angle list (m)	deg
ld	Ld matrix (n x m)	H
lq	Lq matrix (n x m)	H
psim	Psim matrix (n x m)	Vs
psid	Psid matrix (n x m)	Vs
psiq	Psiq matrix (n x m)	Vs
torque	Torque matrix (n x m)	Nm

Machine

Attribute	Description	Unit
beta	Beta list	deg
plfe1	Iron losses stator	W
plfe2	Iron Losses rotor	W
plmag	Magnet losses	W
plcu	Winding losses	W
pltotal	Total losses	W
plfe	Total Iron losses	W
lfe	Length of armature	m
eff	Efficiency	%
m	Number of phases
p	Number of pole pairs
p_sim	Number of poles in model
Q	Total number of stator slots
p2	Mechanical power	W
i1	Phase current	A
A	current loading	kA/m
J	current density	A/mm2
kcu	copper fill factor	%
AJ	Therm loading	A/cm.mm2
torque	Torque	Nm
fd	Force density	N/mm²
ld	Ld Inductance	H
lq	Lq Inductance	H
r1	Stator resistance	Ohm
psim	Magn flux	Vs
n	Speed	1/s
lpfe1_0	Iron Losses in stator at noload	W
lpfe2_0	Iron Losses in rotor at noload	W
lpmag_0	Magnet losses at noload	W
pocfile	Name of POC file used

Example:

{'m': 3,
'p': 4,
'qs_sim': 12,
'p_sim': 2,
'Q': 48,
'n': 50.0,

'kcu': 40.0,
'r1': 0.055,
'AJ': 84365.4609,
'A': 213.2994,
'fd': 119.0008,
'J': 39.5526,

'lfe': 0.08356,
'ld': 0.0008625,
'lq': 0.00132,
'psim': 0.1152,

'torque': 405.7295,
'p2': 127463.7,

'plfe1_0': 172.9209,
'plmag_0': 0.0239,
'plfe2_0': 0.7076,
'i1': 500.0,
'beta': [0.0, -25.0],

'plfe1': [1463.3809, 1374.8728],
'plfe2': [71.727, 77.0296],
'plmag': [4.1524, 15.1965],
'plcu': [10305.4824, 10305.4824],
'pltotal': [11844.7427, 11772.581300000002],
'plfe': [1535.1079000000002, 1451.9024000000002]
'eff': 91.5449}

DqPar

Attribute	Description	Unit
beta	Beta list	deg
lfe	Length of armature	m
npoles	Number of poles
cosphi	Power factor
ld	Inductance Ld	H
lq	Inductance Lq	H
psid	Flux in d-axis	Vs
psiq	Flux in q-axis	Vs
psim	Magnetizing Flux	Vs
psim0	Magnetizing Flux at no-load	Vs
u1	Terminal voltage	V
u1_sim	Terminal voltage (Sim)	V
u1_fe	Terminal voltage (FE)	V
up	MMF voltage	V
up0	MMF voltage at-noload	V
gamma	Angle between Up and U1	deg
i1	Phase current	A
phi	Angle between U1 and I1	deg
p2	Mechanical power	W
torque	Torque	Nm
torque_sim	Torque (Sim)	Nm
torque_fe	Torque (FE)	Nm
kt	Torque factor (peak)
dag	Airgap diameter	m

Example:

{'i1': [0, 243.3, 243.3],
'beta': [0.0, -35.54],
'ld': [0.0005299380000000001, 0.0005299380000000001],
'lq': [0.0012425400000000003, 0.0014455000000000002],
'torque': [444.97800000000007, 829.0680000000001],
'kt': [2.41],
'psim0': 0.10266,
'up0': 258.0,
'psim': [0.10320280000000001, 0.10320280000000001],
'speed': 66.66666666666667,
'npoles': 12,
'lfe': 0.11800000000000001,
'dag': 0.3132,
'u1': [258.0, 805.1564407729971, 727.4119501308116],
'gamma': [70.67427472336531, 83.94107114196522],
'phi': [70.67427472336531, 48.401071141965225],
'cosphi': [0.33093811730811373, 0.6639122324852806],
'psid': [0.10320280000000001, 0.028249200000000002],
'psiq': [0.30231600000000003, 0.28615],
'torque_fe': [452.0, 836.0],
'torque_sim': [444.9, 829.0],
'p2': [186391.9487745439, 347279.1917501844],
'u1_fe': [801.6, 722.6],
'u1_sim': [802.9, 722.6],
'up': [259.3769266479174, 259.3769266479174]}

Magnet

Attribute	Description	Unit
Br	Remanence	T
Hc	Coercitivity	kA/m
muer	rel Permeability
Tmag	Temperature	°C
alpha	Temperature coefficient of Br	1/K
demag_pc	Demag Limit	%
demag_hx	Demag Limit	kA/m
area	Area	mm²
sigma_PM	El. Conductivity	S/m

Example:

{Br': 1.2,
'Hc': -909.457,
'muer': 1.05,
'Tmag': 120.0,
'alpha': -0.1,
'demag_pc': 95.0,
'demag_hx': -863.984,
'area': 4136.087,
'sigma_PM': 625000.0}

Weight

Attribute	Description	Unit
total	Total weight	kg
conductor	Weight of conductors	kg
magnet	Weight of magnets	kg
iron	Weight of active iron	kg

Example:

{'total': 28.188,
'iron': 24.165,
'conductor': 2.853,
'magnet': 1.17}

Weights

List of weights (iron, conductors, magnets): in stator and rotor in kg

Example:

[[18.802, 2.853, 0.0],
 [5.363, 0.0, 1.17],

Inertia

List of inertia (Stator, rotor) [Unit kg m²/mm]

Example:

[0.23, 0.39]

Windings

Dictionary with winding key:

Attribute	Description	Unit
dir	list of winding directions
N	list with number of conductors
R	list of radius	m
PHI	list of angles	deg

Example:

{  1: {'N': [4.0, 4.0, 4.0, 4.0],
       'R': [92e-3, 92.0086, 92e-3, 92e-3],
       'dir': [1, 1, 1, -1],
       'PHI': [3.0203, 4.4797, 11.9797, 40.5202]},
   2: {'N': [4.0, 4.0, 4.0, 4.0],
       'R': [92e-3, 92e-3, 92e-3, 92.0086],
       'dir': [1, 1, 1, 1],
       'PHI': [25.5202, 33.0202, 34.4797, 41.9797]},
   3: {'N': [4.0, 4.0, 4.0, 4.0],
       'R': [92e-3, 92e-3, 92e-3, 92e-3],
       'dir': [-1, -1, -1, -1],
       'PHI': [10.5202, 18.0202, 19.4797, 26.9797]}
}

Losses

List of dictionaries with losses for noload and load calculation:

Attribute	Description	Unit
beta	angle I Up	°
current	winding current (RMS)	A
staza	losses in stator teeth	W
stajo	losses in stator yoke	W
rotfe	losses in rotor	W
winding	losses in windings	W
magnetB	losses in magnet (B-Method)	W
magnetJ	losses in magnet (J-Method)	W
total	total losses	W
r1	winding resistance	Ohm
fft	dict of harmonic spectrum losses rotor, staza, stajo with: order, freq, hyst, eddy

Example:

{'beta': 0.0,
 'current': 0.0,
 'magnetB': 0.0,
 'magnetJ': 0.053,
 'r1': 0.0,
 'rotfe': 483.806,
 'stajo': 1242.913,
 'staza': 1664.52,
 'total': 3391.292,
 'winding': 0.0,
 'fft': {
    'rotor': {'eddy': (475.937,),
              'freq': (600.0,),
              'hyst': (7.869,),
              'order_el': (6,)},
    'stajo': {'eddy': (15.777, 138.777, 394.427, 206.489, 313.927, 134.139, 5.329),
              'freq': (100.0, 300.0, 500.0, 700.0, 900.0, 1100.0, 1300.0),
              'hyst': (9.983, 9.178, 9.391, 2.508, 2.307, 0.66, 0.019),
              'order_el': (1, 3, 5, 7, 9, 11, 13)},
    'staza': {'eddy': (13.06, 117.544, 325.934, 212.208, 417.321, 326.528, 220.231),
              'freq': (100.0, 300.0, 500.0, 700.0, 900.0, 1100.0, 1300.0),
              'hyst': (8.135, 7.774, 7.76, 2.578, 3.067, 1.606, 0.776),
              'order_el': (1, 3, 5, 7, 9, 11, 13)}}
 }

Demag

List of dictionaries with demagnetization information

Attribute	Description	Unit
displ	rotor position	°
current	winding current (RMS)	A
beta	angle I Up	°
current_1	current winding 1 (RMS)	A
current_2	current winding 2 (RMS)	A
current_3	current winding 3 (RMS)	A
H_max	maximum field strength	kA/m
H_av	average field strength	kA/m
area	area with H > Hx	%

Leak_dist_wind

Dict with end-winding leakage values (version added 0.9.9)

Attribute	Description	Unit
nseg	Number of segments
npolsim	Number of poles in model
fc_radius	Force radius (center of airgap	m
armatureLength	Lenght of armature	m
perimrad	Radius of perimeter	m
vbendrad	Bending radius vertical	m
endheight	End winding height	m
wiredia	Diameter of wire	m
L0e	Ext. Inductance	H
Lde	Ext. Inductance	H
Lqe	Ext. Inductance	H
L0i	Int. Inductance	H
Ldi	Int. Inductance	H
Lqi	Int. Inductance	H

scData (Short Circuit)

Dict values of short circuit calculation (version added 0.9.30)

Attribute	Description	Unit
speed	Speed	1/s
ikd	stationary phase current amplitude	A
tkd	stationary Torque	Nm
iks	Peak Current	A
tks	Peak Torque	Nm
time	Time vector	s
ia	Phase a Current vector	A
ib	Phase b Current vector	A
ic	Phase c Current vector	A
peakWindingCurrents	peak current of each phase	A

characteristics

List of Dict values of Characteristics of Permanent-Magnet-Motors

Attribute	Description	Unit
u1nom	Voltage (operat. limit) RMS	V
i1nom	Current (operat. limit) RMS	A
beta0	Angle I vs Up (speed = 0)	Deg
r1	Stator winding resistance	Ohm
Ldnom	Ld Inductance I, Angle I-Up	H
Lqnom	Lq Inductance I, Angle I-Up	H
Pnom	Power	W
Le	Le end winding inductance	H
Lex	Ext. Inductance	H
psinom	Magn. Flux RMS	Vs
lfe	Eff armature length	m
nc	Power cut off speed	rpm
p	Number of pole pairs
i1max	max. current (RMS)	A
relw	Rel number wdg turns
m	number of phases
nmin	min. speed	rpm
nmax	max. speed	rpm
speed_torque	speed torque characteristics
ldq	Ld, Lq, Psi_mag, Torque Table

current_angles

list of current angles from no load test (Example: [30.0, 150.0, 270.0])

powerSituation

dict of windings and beta. Values for each phase:

Attribute	Description	Unit
voltage	voltage	V
current_1	current	A
beta	angle I vs Up	deg
cosphi	power factor
powerp	True Power	W
powerq	Reactive Power	VA