1
Technik und Informatik / Wissens- und Technologietransfer
IRON LOSS CALCULATION OF AN INTERNAL
PERMANENT MAGNET SYNCHRONOUS
MACHINE FOR A FUEL CELL CAR
Electric Drive System Research Activities at
Bern University of Applied Sciences
Engineering and Information Technology
Prof. Andrea Vezzini, Switzerland
Dr. sc. techn. ETHZ
easc-2009, July 7th 2009
2
Technik und Informatik / Wissens- und Technologietransfer
About the Speaker
Dr. Andrea Vezzini
• Professor for Industrial Electronics
since 1996 at Bern University of
Applied Sciences (BFH TI) Biel
• Co-founder and Chairman of the
Board of drivetek ag since 2002
• 2003 Visiting Guest Professor at
General Motors Advanced
Technology Center in Torrance
(7 Months)
• 2007 Distinguished Visiting
Scientist at Commonwealth
Science and Industrial Research
Organisation (CSIRO), Australia
(5 Months)
• Together with drivetek ag
currently involved in projects with
Bombardier Transportation AG,
General Motors and Porsche
Motorsport
3
Technik und Informatik / Wissens- und Technologietransfer
BFH Engineering and
Information Technology
•
•
•
•
•
•
Established in 1890
Since 1998 Part of Bern
University of Applied Sciences
6 Divisions with a total of
1’300 students, second biggest
in Switzerland
External Turnover with
aR&D 2008:
approx. 8 Mio. CHF
(+ 2.5 Mio. CHF internal
funding)
Strategic Programs in Fuel Cell
Development, Automotive
Systems and Renewable
Energy
Over 10 Innovation prices
since 1993
Technik und Informatik / Wissens- und Technologietransfer
spin-off Success
drivetek ag was founded in
2002 as a fully independent
spin-off of the Laboratory of
Industrial Electronics. Eleven
Engineers work on high
efficient drives and power
electronics for energy,
automotive, space and
automation applications. It’s
the creation of jobs and
industrial impulses which has
become one of the most
challenging but also exciting
tasks of the Berne University
of Applied Sciences
http://www.drivetek.ch
5
Technik und Informatik / Wissens- und Technologietransfer
Content
•
•
•
•
Internal Permanent Magnet Synchronous Motor Fundamentals
Design Flow
Core Loss Calculations
Examples
“The outcome of any serious research can only be to make two questions grow where only one
grew before.”
Thorstein Veblen
US economist & social philosopher (1857 - 1929)
6
Technik und Informatik / Wissens- und Technologietransfer
Types of PM Synchronous
Motors
• The amount of PM-generated
magnetic flux linked by the coils of the
stator remains fixed.
• As a result, the back-electromotive
force (back-emf) voltage induced by
the PMs increases linearly with the
speed of the rotor.
• As the rotor speed increases the backemf voltage rises, which results in a
rapid reduction in the available
voltage, (the difference between the
supply voltage and the back-emf).
When there is no longer any voltage
available to drive current into the
stator, the maximum speed has been
reached.
• Depending on the rotor geometry, PM
Synchronous show different torquespeed behavior.
a)
b)
a) Surface Permanent
Magnet Motor
b) Inset Permanent
Magnet Motor
c) V-Shaped Single
Layer IPM
d) V-Shaped Double
Layer IPM
e) U-Shaped Double
Layer IPM
d)
c)
e)
7
Technik und Informatik / Wissens- und Technologietransfer
Saliency
• Saliency: different d- and
q-axis inductance, based of
different rotor
permeability in q- and daxis
• Salient pole machine allow
for an extended constant
power speed range (CPSR),
required in a multitude of
application.
• Combined with weak flux
bonded PM (PM-Assisted
SRM) and laminated rotor
to reduce rotor losses

Lq
Ld
Technik und Informatik / Wissens- und Technologietransfer
Design of PM Synchronous
Machines
• Normalized System Equations
• Surface Mounted PM SM has Saliency
 = 1 and maximum torque current
angle g = 0
• Synchronous Reluctance Machine has
Ym = 0
• IPM Design Freedom:
• With strong magnetic field from PM
Magnets -> conventional IPM
• With weak magnetic field from PM
Magnets -> PM Assisted SRM
Magnetic Torque
Reluctance Torque
q-axis
 d-q-axis diagram
jwLqIq
• Field Weakening Operation
• For surface mounted PMs, where Lq =
Ld, Id in the negative direction weakens
the magnet so that the motor may be
driven at higher speeds. However,
there is no increase in output power,
while the input power must increase
to supply the additional resistance
heat loss.
RI
jwLdId
I
V
Vq
Iq
Vd
Eq=wYm
j
Id
g
d
b
d-axis
9
Technik und Informatik / Wissens- und Technologietransfer
IPM Constant Power Speed Range / Field Weakening
q
Tmax = f(Imax, g)
base speed
point
Torque vs. Speed (Normalized)
Imax
CPSR
d
0.8
wc, vmax
0.6
0.4
infinite
speed point
0.2
0
0
1
2
3
4
q-axis
• The possible operating points are limited within the current
circle and the voltage ellipse. The voltage ellipse will
decrease its size with increasing speed.
• Maximum torque above base speed is only possible by
increasing the current angle
• Depending on the placement of the infinite speed point three
different design options are available: finite speed, optimum
infinite speed and infinite speed type
q-axis
I
II
q-axis
I
II
gm
Y
 mn
Ldn
I
II
gm
Y
 mn
Ldn
d-axis
gm
III
d-axis
Y
 mn
Ldn
d-axis
10
Technik und Informatik / Wissens- und Technologietransfer
IPM Design Possibilities
• IPM magnetic flux and saliency can be matched for ideal fit of machine
characteristics to car requirements
• Lower magnetic flux can be compensated with higher saliency with the added
benefit of lower current per torque requirements (for the same per unit torque
and CPSR)
Technik und Informatik / Wissens- und Technologietransfer
x
Wheel torque vs. Vehicle Speed; m=720kg, different Acceleration Profile, Power and Grade
1400
Optimized Motor Choice
0-400m@17.3sec 0%
0-100km/h@10.2sec 0%
1200
• Based on the limits from the different
requirements, the possible motor specs (base
speed and nominal torque are plotted. The
red line is the combined curve all the motor
specs, which will fulfill all the requirements.
The three crosses are exemplary motor
designs.
Wheel Torque [Nm]
1000
x
800
68kW
40-80km/h@5sec 8%
64kW
60kW
80-120km/h@8sec 0%
56kW
52kW
Superposition
48kW
44kW
x
40kW
36kW
600
30%
32kW
28kW
20%
24kW
20kW
400
10%
200
6%
3%
Energy [% of total] for 38 km Pendler Cycle
3.5
0%
0
200
1000
3
600
800
1000
Speed / Base Speed [rpm]
Speed vs. Power, Torque, CPSR, m=720kg
23kW - Cont Pow er
1400Nm – 40kW
925Nm – 40kW
700Nm – 64kW
2500
2
Torque for a=0 @ 0%
2000
1.5
-500
1
0.5
Torque [Nm]
0
0
20
40
60
80
Speed[km/h]
100
120
ZH-Pendler Drive cycle: Torque and Acceleration
140
100
80
x
1500
60
Pow er
1000
x
-1000
0
1400
120
2.5
500
1200
3000
45kW - Peak Pow er
Torque[Nm]
400
40
Torque
x
500
20
CPSR ((V max - V base) / V base)
0
0
100
200
300
400
500
600
700
Speed / Base Speed [rpm]
800
900
0
1000
Power [kW] and 10*CPSR [ ]
0
Technik und Informatik / Wissens- und Technologietransfer
Step
FEA Process Overview
Design of a lumped parameter
Model
Model Definition
Verification
Analysis in Maxwell
Verification
Parametric Analysis in
Maxwell
Result Analysis in Matlab
Efficiency Analysis
Generic Motor
Model Design
Adjustments on the
Motor Model
(definition of Geometry, Material, etc.)
Simulation of the
Model
- Analysis in Maxwell
If Results are ok:
- Parametric Analysis
Result Analysis with
Matlab
Efficiency Map
Simulation
Technik und Informatik / Wissens- und Technologietransfer
Maxwell –Matlab toolchain:
Analysis of FEA Result Data
•
Import Data
Import Raw Data from Maxwell (Magnetic Flux, Phase Current, Current, Rotation Data,
Torque, Voltage)
Transient Simulation of a 2d-Model over 110
different current amplitude and angle cases
over one electrical period
Simulation data is saved after each transient
run (torque, flux)
•
Ansoft LLC
d-q Transformation
Transform flux and current into d-q representation
Interpolate Data
Interpolate Data into uniform distributed arrays
Maxwell2DDesign2
InducedVoltage
30.00
Curve Info
rms
InducedVoltage(phaseA)
InducedVoltage(phaseB)
20.00
Calculate Results over Speed Range
14.5148
back_emf : Transient
14.5050
back_emf : Transient
InducedVoltage(phaseC)
Calculate the Results over the complete Speed Range of the Motor
14.5043
back_emf : Transient
Y1 [V]
10.00
0.00
Calculate Parameters for Efficiency Map
-10.00
Calculate the Parameters for the Efficiency Map FEA
-20.00
Ansoft
LLC
-30.00
0.00
5.00
Maxwell2DDesign2
Torque
10.00
15.00
Time [ms]
35.00
20.00
25.00
Moving1.Torque
load_losses : Transient
30.00
Plot Results
30.00
Curve Info
avg
24.0803
Calculate and Display the Result Plots
Moving1.Torque [NewtonMeter]
25.00
•
20.00
15.00
10.00
5.00
0.00
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
Time [ms]
4.50
5.00
5.50
6.00
6.50
7.00
7.50
•
A set of matlab functions performs the
necessary operations to calculate the
Results of the Motor from the FEA Results.
The Results will then be displayed and
compiled into a pdf Report
14
Technik und Informatik / Wissens- und Technologietransfer
Search optimal Current and
Current Angle
• Calculation of Continuous and
Peak Requirement Current and
Current Angles with a maximum
Torque Per Ampere Approach
(minimizing the Copper Losses)
• Possible Torque Operation points
are reduced with increasing
speed, as voltage circle
decreases. In this case the
current angle has to be increased
and/or the current amplitude
decreased (Type II)
Airgap Torque Tem as a Function of Control Angle g and Peak Current
1
27
50
7
23
40
23 7
30
169
16 9
135
10
1
67
67
10 33
33
-10
-20
33
-30
-40
-50
-60
Control Angle g [°DEG]
-70
-80
10
617
-90
339

Base Point: 7900Magnet
rpm
305
271
100
27
1
23
7
20 3
203
50
169
169
40
135
135
30
101
101
67
120
: 140°C
Iphmax :240A rms
237
60 203
20
67
330
29275317
5
20163193
0
13
5
101
10 1
20
Iphmax :240A rms
203
20 3
13 5
Magnet: 140°C
23 7
333095
27 13 7
2
3
20 9
16
Airgap Torque [Nm]
60
27
1
27 1
339
80 305
271
70
237
5
30
5
30
9
33 5
30
9
33
70
90
Winding: 180°C
30 5
67
23
7
16 9
13 5
q-axis current iq [Arms ]
80
0
 Tmax : 88.7 Nm, @ g: -55.2°
33 9
d- and q-axis current for the whole operating speed range
140
Winding: 180°C
100
Peak Torque Tmax [Nm]
90
Maximum Torque Tmax over Speed Range
80
60
Iphmax :240Arms
67
20
Constant Torque Speed Range
Constant Power Speed Range
mech. and iron losses not included
0
5000
10000
Mechanical Speed [rpm]
Magnet: 140°C
40
10 1
10
0
Winding: 180°C
15000
0
-200
-150
-100
d-axis current id [Arms ]
-50
0
Technik und Informatik / Wissens- und Technologietransfer
Why not calculated Performance Curves from one single point of operation?
d-axis Flux d as a Function of Control Angle g and Peak Current
d-axis Inductance Ld as a Function of Control Angle g and Peak Current
Load and No-Load Phase Voltage over Speed Range
33
10 1
Winding: 180°C
-0.02
Magnet: 140°C
-0.03
Iphmax :240Arms
-10
-20
101
13 5
16 9
20 3
23 7
169
203
27
1
30
5
33
9
23 7
27 1
300
0.08
30 5
200
-30
-40
-50
-60
Control Angle g [°DEG]
-70
100
50
-80
-90
-10
33
2 270359
20 3 7 1
3
Magnet: 140°C
Iphmax :240Arms
3323079517
2230 3
9
16 5
13 1
10
q-axis Flux q [Vs]
16 9
13 5
67
0.04
33
67
33
0.02
33
573
0
33
01
29237
239
1
1163105
0.01
0
0
-10
-20
-30
-30
-40
-50
-60
Control Angle g [°DEG]
-70
-80
-40
-50
-60
Control Angle g [°DEG]
-70
-80
67
33
-90
33
67
33
200
150
100
Iphmax :240Arms
Magnet: 140°C
50
0
-90
101
135
169
203
237
271
305
339
101
Winding: 180°C
67
0.03
-20
No-Load Peak Phase to Phase Voltage @ 15000rpm: 434.3 V
250
Winding: 180°C
0
5000
10000
Mechanical Speed [rpm]
q-axis Inductance Lq as a Function of Control Angle g and Peak Current
10 1
0.05
Magnet: 140°C
900
3
30359
27
23 71
20 3
101
0.06
Winding: 180°C
150
33 9
169
135
0.07
33
67
101
135
169
203
237
271
305
339
Iphmax :240Arms
800
q-axis Inductance Lq [  Henry]
339
30 5
27 1
23 7
20 3
33
67
101
135
169
203
237
271
305
339
250
q-axis Flux q as a Function of Control Angle g and Peak Current
0.09
101
135
169
203
67
237
271
305
33
339
350
67
0
-0.01
33
10 1
13 5
16 9
20 3
23
7
27
1
30
335
9
0.01
0
33
67
13
0.04 165
2093
23
277
0.03
310
335
9
0.02
d-axis Inductance Ld [  Henry]
d-axis Flux d [Vs]
0.05 67
Load and No-Load Phase Voltage (Peak Value) Vph [Vp]
400
67
135

q-axis
d-q-axis diagram
101
RI
169
jwLdId
203
135
500
169
203
237
271
305
339
400
300
237
271
305
339
Magnet: 140°C
100
Iphmax :240Arms
0
-10
-20
-30
-40
-50
Control Angle g [°DEG]
-60
-70
The effects of saturation on Ld and Lq are affecting the voltage equations
and as a consequence the calculation of the dq-axis diagram
Vq
-80
Iq
Vd
Lq
Ld
Eq=wYm
I
V
Winding: 180°C
200

jwLqIq
700
600
15000
j
Id
g
d
b
d-axis
Technik und Informatik / Wissens- und Technologietransfer
Efficiency Map
•
Points for efficency Parametric Analysis
Calculate Simulation Parameters for
Simulation Points
30
Maxiumum Requirements
Simulation Points
25
(Current, Current Angle, Rotation Speed, Simulation Time)
•
Write Parameters as Variables into
Maxwellscript file for Simulation
Simulation over at least two electrical
periods for each operation point in Maxwell
Torque [Nm]
•
20
15
10
5
Ansoft LLC
Maxwell2DDesign2
FluxLinkage
0.06
FluxLinkage(phaseB)
load_losses : Transient
FluxLinkage(phaseC)
load_losses : Transient
FluxLinkage(phaseA)
load_losses : Transient
0.0523
0.04
0.0523
0.02
0.0523
0.00
-0.02
-0.04
-0.06
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
5.50
6.00
6.50
7.00
7.50
Time [ms]
Ansoft LLC
Maxwell2DDesign2
CoreLoss
300.00
Curve Info
CoreLoss
load_losses : Transient
avg
max
210.6362
238.0068
250.00
CoreLoss [W]
200.00
150.00
100.00
50.00
0.00
0.00
0.50
0
max
1.00
1.50
2.00
2.50
3.00
3.50
4.00
Time [ms]
4.50
5.00
5.50
6.00
6.50
7.00
7.50
Y2 [Wb]
Curve Info
0
2000
4000
6000
8000
Speed [rpm]
10000
12000
14000
17
Technik und Informatik / Wissens- und Technologietransfer
Comparison of Maxwell Iron Loss Calculation with Measurement Data
100.00
Core Loss Calculation
Measured values as dots.
Calculated lines are based
on Maxwell Coefficients
Kh, Kc and Ke, which have been
calculated for each frequence
accordingly.
80.00
70.00
SPecific Core Losses [W/kg]
• Improvement of V12 by using multifrequency data. Eliminates need to change
data at each simulation step
• Maxwell uses dB/dt approach and not a
fourier series Steinmetz based formula. This
yields better results but requires at least
two electrical periods of simulation data
90.00
60.00
Meas. 100Hz
Meas. 200Hz
Meas. 400Hz
Meas. 1000Hz
Meas. 2000Hz
Meas. 5000Hz
50.00
Meas. 10000Hz
100Hz
40.00
200Hz
400Hz
30.00
1000Hz
2000
20.00
5000
10000
10.00
0.00
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
0.90
1.00
1.10
1.20
1.30
1.40
1.50
Induction Value [B]
Comparison of Maxwell Iron Loss Calculation with Measurement Data
100.00
90.00
Measured values as dots.
Calculated lines are based
on Maxwell Coefficients
Kh, Kc and Ke, which have been
calculated 100Hz data.
80.00
SPecific Core Losses [W/kg]
70.00
Meas. 100Hz
Meas. 200Hz
Meas. 400Hz
Meas. 1000Hz
60.00
Meas. 2000Hz
Meas. 5000Hz
50.00
Meas. 10000Hz
100Hz
40.00
200Hz
400Hz
30.00
Referenzpaper:
D. Lin, P. Zhou, W. N. Fu, Z.
Badics, and Z. J. Cendes: “A
Dynamic Core Loss Model for
Soft Ferromagnetic and Power
Ferrite Materials in Transient
Finite Element Analysis”
1000Hz
2000Hz
20.00
5000Hz
10000Hz
10.00
0.00
0.00
0.10
0.20
0.30
0.40
0.50
0.60
0.70
0.80
Induction Value [B]
0.90
1.00
1.10
1.20
1.30
1.40
1.50
18
Technik und Informatik / Wissens- und Technologietransfer
Problems with Core Loss Calculations using different number of triangles
27343 triangles
torque
(N-m)
average coreloss average
56.2
(W)
1903
29591 triangles
torque
(N-m)
average coreloss average
56.3
(W)
1791
48638 triangles
torque
(N-m)
average
56.3
coreloss average
(W)
1590
The three models with different number of triangles were used to simulate
the same load point using impressed currents in the phases(11k rpm,
250Arms, 77.7 DEG current angle -> meas. torque of 59.875Nm and
corelosses of 1412W). Apparently the torque calculation is not changing
with the number of triangles, where as the core losses decrease with
increasing numbers of triangles.
19
Technik und Informatik / Wissens- und Technologietransfer
Ansoft LLC
Core Loss Calculation
Methods
CoreLoss [W]
50.00
Simplest Model, fast
convergence
P4 Phase Current measured at 5000rpm and 200Nm
600
0.00
0.00
PWM voltage supply model
•
•
Either in Maxwell or combined
with Simplorer.
Long simulation time,
especially if mechanical model
is used.
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
5.50
6.00
6.50
7.00
7.50
Time [ms]
400
Ansoft LLC
Maxwell2DDesign2
CoreLoss
2.40
long Convergence time
Taken from simulation data,
good behavior, medium
convergence (2 electrical
periods), but needs high
resolution
Taken from measurement
data for verification, needs
treatment
0.50
Curve Info
2002.20
CoreLoss
current_model_losses : Transient
avg
max
0.2628
2.4395
2.00
1.80
1.60
01.40
1.20
1.00
0.80
-200
0.60
0.40
0.20
-4000.00
0.00
0.50
1.00
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
5.50
6.00
6.50
7.00
7.50
Time [ms]
-600
0
0.2
0.4
0.6
0.8
1
1.2
Sampling Points []
1.4
1.6
1.8
2
4
x 10
phase voltage over electrical position
airgap torque over electrical position
600
500
200
airgap torque [Nm]
•
•
100.00
Impressed PWM currents
•
238.0068
150.00
CoreLoss [kW]
•
max
210.6362
200.00
Sinusoidal voltage supply and
RL-parameter for winding
•
avg
250.00
Phase Current Ip [Ap]
•
CoreLoss
Impressed sinusoidal stator
currents
•
Curve Info
load_losses : Transient
phase voltage [Vp]
•
Maxwell2DDesign2
CoreLoss
300.00
150
100
400
300
200
50
100
0
0.9
1
1.1
1.2
1.3
time [s]
1.4
1.5
0
1.6
x 10
-3
0
0.02
0.04
0.06
0.08
electrical position [°DEG electrical]
0.1
20
Technik und Informatik / Wissens- und Technologietransfer
No Load Core/Iron Losses
1400
Results for no load and sinusoidal
current excitation
4.00
y = -4.18381E-11x3 + 5.60691E-06x2 + 3.27622E-02x
R² = 9.96694E-01
3.50
1200
3.00
•
•
•
No load core losses are easy to
calculate and have no influence
from stator current or PWM Voltage
Supply
Drag losses (for example in an
electric rear axle hybrid drive at
high speed driving) are important.
To calculate the influence of active
field weakening at no load is
therefore important.
The Iron Losses decrease with
increasing d-current The Copper
Losses increase with increasing dcurrent Reduction of 11% of Losses
with d-current field weakening
Average Power (Watts)
1000
2.50
800
2.00
600
1.50
400
1.00
200
0.50
0
0.00
0
2000
4000
measured data
6000
Speed (rpm)
FEA Core Losses
8000
Corrected FEA
10000
12000
Factor
14000
21
Technik und Informatik / Wissens- und Technologietransfer
Using measured Signal Approach: Noise reduction in measured Signal
Measured Signal:
Measured Signal:
Double-Sided Amplitude Spectrum
200
40
Y(t)
50
0
-50
-100
50
0
35
30
25
|Z(f)|
100
Apply FFT and
plot Double
sided
Amplitude
Spectrum
100
Y(t)
Make a
sequence of
the same
signal with a
repetition of
25 to increase
the resolution
of FFT
150
150
20
15
-50
10
-100
-150
5
-150
-200
0
0.5
1
1.5
2
2.5
Time [s]
0
0.05
0.1
0.15
0.2
0.25 0.3
Time [s]
-3
x 10
0.35
0.4
0.45
0
4.5
0.5
5
5.5
6
6.5
Frequency (Hz)
7
7.5
8
5
x 10
Cut higher
frequency
harmonics
Maxwell Current Input Signal
Filtered Signal
200
50
0
-50
40
Apply inverse
FFT and plot
Signal
150
100
35
30
50
25
|Z(f)|
100
Y(t)
150
Y(t)
Double-Sided Amplitude Spectrum
200
Generate the
three input
currents for
Maxwell with
corresponding
control angle
gamma
0
20
-50
15
-100
-100
10
-150
-150
5
-200
0
0.5
1
1.5
2
2.5
Time [s]
3
3.5
4
4.5
-3
x 10
-200
0
0.5
1
1.5
Time [s]
2
2.5
-3
x 10
0
4.5
5
5.5
6
6.5
Frequency (Hz)
7
7.5
8
5
x 10
22
Technik und Informatik / Wissens- und Technologietransfer
Ansoft LLC
Maxwell2DDesign2
CoreLoss
400.00
load_losses : Transient
avg
max
297.9682
334.7978
300.00
250.00
CoreLoss [W]
• Core loss computation is treated as
"post process" in Maxwell 2D
transient, that is, the core loss
effects on the field are ignored.
• If the core loss effects on the field
are taken into account, when there
is a spike in an excitation, the core
loss spike will reduce the field
change, which in tune reduces the
core loss spike.
• In Maxwell 3D transient, we can
consider core loss effects on the
field.
• Unfortunately, Maxwell 2D transient
does not support this at present
CoreLoss
350.00
200.00
150.00
100.00
50.00
0.00
7.50
8.00
8.50
9.00
9.50
10.00
10.50
11.00
11.50
12.00
12.50
13.00
13.50
14.00
14.50
15.00
Time [ms]
Ansoft LLC
Maxwell2DDesign2
CoreLoss
16.00
Curve Info
CoreLoss
14.00
current_model_losses : Transient
avg
max
0.8662
15.9693
12.00
10.00
CoreLoss [kW]
Core Loss calculation
problems in Ansoft 2D
Curve Info
8.00
6.00
4.00
2.00
0.00
0.00
0.50
1.00
Core Losses: Proto II, 360V, 4‘000rpm, 60Nm
Average: 336.8352W
1.50
2.00
2.50
3.00
3.50
4.00
4.50
5.00
5.50
6.00
6.50
7.00
7.50
Time [ms]
900
800
700
600
Core Losses [W]
• Results on the right:
• Core Losses sinusoidal
Current: 298W
• Core Loss PWM Current from
Simulation: 866W
• Core Loss PWM Current from
Simulation, only Losses up to
8’00W taken into account:
337W
500
400
300
200
100
0
0
0.5
1
1.5
2
2.5
3
3.5
4
time [ms]
4.5
5
5.5
6
6.5
7
7.5
23
Technik und Informatik / Wissens- und Technologietransfer
Conclusions
•
•
•
•
Influence of PWM Supply on core losses is an important factor for the efficiency
calculation of the motor as all of today's motor are based on PWM supply. In fully
optimized systems efficiency gains in the motor due to higher PWM are optimized
versus the higher switching losses in the Inverter.
Iron Loss Calculation becomes an important task in the motor simulation process due
to need for efficiency map calculation and optimization over the whole torque and
speed range
Computational Capabilities are still somehow limited and are based on manufacturer
data with limited reliability due to old measurement setups. Manufacturer should
modify test equipment to include higher frequencies and additional rotational losses
Motor designers are used to 2D simulations to limit simulation time, fully transient
simulation including taking into account the influence of eddy currents on the
magnetic field should be therefore brought to Maxwell 2D as fast as possible
Technik und Informatik / Wissens- und Technologietransfer
MITRAC
Permanent Magnet Motor
•
Environmentally sound use of resources
•
Energy costs per Light Rail Vehicle about
40‘000 $US/year (~50t LRV)
•
Energy costs per Metro train about
200‘000 $US/year (~230t train)
•
•
•
Tested and validated, the solution’s innovative
motor construction is based on internal
permanent magnet technology. It uses a rotor
to create its own flux by incorporating magnets.
The MITRAC Internal Permanent Magnet Motor
meets the highest demands on drive systems
for traction application.
Bombardier recently tested the MITRAC
Permanent Magnet Motor in Sweden.
Bombardier replaced four forced air-cooled
induction motors in the BOMBARDIER REGINA
with two of the PM motors as part of the Gröna
Tåget (“Green Train”) project.
The successful tests confirmed that a reduction
of two induction motors could be achieved
while still providing the same performance for
the REGINA train.
Left: Forced air-cooled Regina induction motor. Right:
Permanent Magnet Motor prototype tested on Regina
summer 2008.
25
Technik und Informatik / Wissens- und Technologietransfer
Research and Development Examples
Equinox Fuel cell Car, General Motors, USA
New SAM: Cree AG, 2009, Switzerland/Poland
ECUV, Sun Ya-Tsen University/HYB, China
Angel Interceptor, domteknika AG, Switzerland
26
Technik und Informatik / Wissens- und Technologietransfer
Electric Motor Glider
ANTARES (Lange Aviation
GmbH, Dermany)
Brushless PM-Motor
•
•
•
•
•
Outside runner with phase
voltage optimized for block
commutation providing best
torque density
high torque (250Nm) at low
speed (1‘500 prm) and high
efficiency (92%) at low mass
(28.5kg)
completely integrated rotor
design; rotor acts as case with
direct mounted propeller
blades
Air Cooling by large inside
diameter
Series Production by Servax
Landert Motoren AG
27
Technik und Informatik / Wissens- und Technologietransfer
Thank you very much for your attention
Dr. Andrea Vezzini
Laboratory for Industrial Electronics
Berne University of Applied Sciences
Tf.: +41 32 321 63 72
Fax: +41 32 321 65 72
email: andrea.vezzini@bfh.ch
Internet: www.ti.bfh.ch