By Jim Hendershot

By Jim Hendershot
SMMA 2011 Fall Technical Conference
Renaissance Charlotte Suites Hotel
November 8-10, 2011
Welcome
For most of the last century two electric machine types
dominated the world for for most all electric motoring
applications. These two well recognized electric motor
types are known as AC induction & DC commutated.
In the last part of the the 20th century new motor types
emerged and became popular because of the computer
and power semiconductors plus the desire for motion
control improvements including variable speed.
One of the most popular machine types in the last 25
years has been the DC brushless machine or now called
PMAC synchronous motors and generators.
2
First motors emerged inside our bodies !!
3
The PM brushless machines now comes all shapes and
forms for a variety of popular applications.
As some had predicted a few years ago, the prices of the
popular “rare earth” magnets has sky-rocketed (up 1400%)
This event has and will continue to cause a response
Clever new magnetic circuits, new magnet supplies as well
as new magnet types and well as alternative motor designs
A very good alternative choice with no magnets is the
inverter driven AC induction machine.
The well known switched reluctance motor type is another
possible choice that some will consider.
4
20th century motor technologies
driven by smart inverters:
Stepping Motors
PM Brushless DC
PM-AC Synchronous (SPM & IPM)
Switched Reluctance Brushless
Reluctance Synchronous
Axial, Radial or Transverse Flux Types
5
BRUSHLESS & PM-AC
SPM & IPM ROTORS
By Tim Miller
6
2010 Prius
Gear Box
GM VOLT
TRACTION
MOTOR
7
8
Cross section of modern AC induction motor
9
Reliance high performance AC Induction Motor.
10
Brushless motors with no magnets
SRM
RSM
Switched Reluctance Reluctance Synchronous
New Mfg. technology
Standard AC motor/stator
Special stator windings
Standard AC phase windings
Robust rotor (no conductors)
Simple rotor (no conductors)
Difficult noise control
Normal induction motor noise
Special Inverter & control
Uses standard AC inverters
11
Switched Reluctance motors with no magnets
12
2 Phase SR motor replaces AD-DC brush type motor
13
2 Phase SR Motor
Low audible noise
Low torque ripple
(4) transistors
(1)  Sensor
(2)  Uni-directional
14
Line-Start RSM motors for hermetics & compressors
By Andrew Frazer, Murdoch University Using Infolytica Magnet
15
RSM vs SRM
(8) POLE RSM
16
Brushless motors with no magnets
AC Induction
RSM
BY ABB
17
Induction Rotor vs Reluctance Synchronous Rotors
ABB
ABB
ABB
19
AC stator, RSM rotor & Induction
Rotor plus 3-phase inverter ABB
RSM
AC Induction
19
RSM rotor substituted
for wound rotor rotor in
AC induction motor.
Three Phase Stator
Induction Rotor
Induction Rotor
Reluctance Synchronous Rotor
Furnished by Prof. Valeria Hrabovcova, & Josef Mihok, University of Zilina
20
Two well known lamination
configurations for RSM’s
Radial insulated with
Radial laminations
Radial insulated with
Axial laminations
IEEE Transactions Energy conversion, Vol 25, No 2, June 2010
21
RSM (reluctance synchronous rotors with
increased radial mechanical stability
by Dr. Jere Kolehmainen, ABB, Finland
IEEE Transactions Energy conversion, Vol 25, No 2, June 2010
22
(4) Pole RSM rotors
Pole
Pole
axis
axis
axis
axis
The flux “barriers” or magnetic flux insulators produce
anisotropy which results in the forming of poles in the rotor.
The resulting saliency produces the poles which are the
preferred magnetic flux paths known as the rotor poles.
Furnished by Prof. Valeria Hrabovcova, & Josef Mihok, University of Zilina
23
24
Reluctance Synchronous Motor catalogue, ISGEV, Italy
MOTORI SINCRONI A RILUTTANZA SERIE “AR”
“AR” SERIES RELUCTANCE SYNCHRONOUS MOTORS
L
AD
AG'
LF
AC
LLxLL
SxZ
ARZIGNANO-Vicenza
GA
TOLLERANZE
Estremit d'albero D:
j6 fino al 28, k6 oltre.
Diametro flangia N: j6 fino al 230,
h6 oltre.
TOLERANCE
End of shaft (D):
j6 up to 28, k6 above.
Flange diameter N: j6 up to 230
h6 above 230.
E
AS
HD
P N D
DB DIN332
AG
F h9
0
H -0,5
BC
T
LE
BA
HA
LA
AA
O
K
A
AB
B
BB
C
NOTE
Dal tipo 132, scatola morsettiera
con 2 bocchettoni pressacavo.
Dal tipo 132, golfare di sollevamento.
NOTE
From Type 132 on up, terminal box
with 2 cable-holder unions.
From Type 132 on up, lifting eyebolt.
Z = Numero dei fori di fissaggio
Number of fastening holes
Dimensioni in millimetri - Dimensions in millimeters
Forma costruttiva IM B35
Assembly IM B35
Flangia B5 - Flange B5
Estremità d'albero - End of shaft
Grandezza/Size
IEC
A AA AB AC AD AG AG' AS B BA BB BC C
63
71
80
90
90
100
112
132
132
160
160
180
180
100
28
120
122 112
60
112
30
136
143 122
125
34
158
166 132
140
40
180
140
40
160
48
H HA HD K
L LE LF LL
O
D DB
E
F GA M N P LA S Z T
DIN 332
45
80
26
97
35
40
63
8
124
7
210
60
94
60
104
189 140
60
112
180
189 140
60
112
45
125
202
215 167
73
131
58
140
23
103
45
90
28
108
34.5
45
71
8
143
7
45
100
32
120
37
50
80
9
163
9
241
30
120
272
40
140
45
100
38
127
29.5
56
90
10
185
9
298
50
156
90
38
152
29.5
56
90
10
46
176
39
63
100
10
185
9
323
50
169
90
208
12
367
60
193
116
90
12.5 115 95 140
7
5
16 130 110 160
6
21.5 165 130 200
50
8
M8
50
M10
60
11
M4
23
4
90
14
M5
30
90
19
M6
40
24
M8
24
28
Tipo pressacavo vedi pag. 5
Type cable gland see page 5
S
L
L
M
S
M
M
L
M
L
84
190
52
228
239 179
73
143
58
140
50
184
35
70
112
11
232
12
388
60
200
116
216
60
260
268 204
83
163
68
140
58
198
38
89
132
13
266
12
448
80
239
136
216
60
260
268 204
83
163
68
178
58
236
38
89
132
13
266
12
486
80
258
136
38
254
65
310
322 245
105 194.5 80
210
70
272
48
108
160
18
322
15
596 110
323
160
42
254
65
310
322 245
105 194.5 80
254
70
316
48
108
160
18
322
15
640 110
345
160
42
279
70
350
366 265
105 214.5 80
241
75
308
45.5 121
180
24
363
15
663 110 351.5 160
279
70
350
366 265
105 214.5 80
279
75
346
45.5 121
180
24
363
15
701 110 370.5 160
3
9.5
4
8
9.5
4 3.5
9
11.5 4 3.5
27 165 130 200
9
11.5 4 3.5
8
27 165 130 200
9
11.5 4 3.5
8
31 215 180 250 10
14
4
4
28
M10
60
8
31 215 180 250 10
14
4
4
38
M12
80
10
41 265 230 300 12
14
4
4
M12
80
10
41 265 230 300 12
14
4
4
M16
110 12
45 300 250 350 15
18
4
5
M16
110 12
45 300 250 350 15
18
4
5
48
M16
110 14
51.5 300 250 350 15
18
4
5
48
M16
110 14
51.5 300 250 350 15
18
4
5
Dati non impegnativi - con riserva di apportare modifiche / These data are not legally binding. The Manufacturer reserves the right to modify its products without notice.
8
25
New 2011 RSM
motor product
line announced
for production
26
Efficiency comparison SynRM (RSM) & Induction motor)
RSM produces zero
ohmic losses in rotor
Data by ABB
27
DESIGN CONSIDERATIONS FOR RSM ROTORS
1- RSM’s of the 60s & 70s utilized starting cages (slide 15)
2- RSM rotor designs require maximum pole saliency
3- Saliency ratio determines d & q inductances
4- Using flux guides to improve saliency or inductance ratio
a- Transverse lamination of the rotor iron pole sections
b- Axial laminations of the rotor iron pole sections
c- Optimize number of flux guides
d- Shaping of flux guides
28
Study of saliency optimization applied
to two pole RSM configurations.
Similar considerations are relative to
Multi-pole RSM rotor configurations also.
29
30
Final comments:
RSM machines could be an alternative for PM machines
Successful designs depend upon maximizing of Ld/Lq
Low investment to convert from AC induction motors
Utilizes standard AC inverter technologies
Could be improved significantly with the use of negative
permeability materials as magnetic flux barriers. (JRH 2011)
(No practical neg. perm. materials exist today but research in under way)
31