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