IEEETRANSACTIONS IEEETRANSACTIONS NINDUSTRYPPLICATIONS. NINDUSTRYPPLICATIONS. OL.26. 26. NO.5.SEPTEMBER/OCTOBER 990
STEP STEPHE HE
901
A. GREE GREER, R, SENI SENIOR ORMEMB MEMBER ER,EE ,EE
a ri ri ou ou s p titi o av vaa ilil a l e f o l ar ar g o rs rs ep ep ow ow e m ilil l Abstract- T b r iv iv e s ys ys t m s a r e x xaa mi mi ne ne d t og og et et h w itit h t h i r i m a ct ct s o n m m e si si g a n r el el at at iv iv e c a i tltl l a n o pe pe r t i n llll ! o st st s i rs rs t b ri ri e h is is t r y o f l ar ar g mill mill driv driv syst system em is i v n . T he he n t at at ee- of of -t -t he he -a -a r i l e si si g a n m e chan chanic ical al desi design gn cons consid ider erat atio ions ns ar disc discus usse sed. d. desi design gn fo fixe fixedd-sp spee ee or variab variablele-spe speed ed operat operation ion Is pres presen ente ted, d, an th capi capita ta an oper operat atio iona na o s f ac ac to to r t ha ha t i nR nR ue ue D e si si g a r o ns ns id id er er e T h c h ho oi of r iv iv e th il li driv driv syst system em desi design gn c ri ri t r i f o e le le ct ct i t h h es es t e si si g f o l ar ar g mills mills is develo developed ped
II. MECHANICALDESIGNCONSIDERATIONS DESIGNCONSIDERATIONS
[1].
ng
ge
nd
il nt ne
to de be
ic
n ev ev e d e t an an d
long long us fu life life
INTRODUCTION
ge
ot
ni ue
24
g, ll
in
v an an c
le
or ho
gh
he
qu
th
ni
to
on th 70 ie ns bega bega deve develo lopi ping ng ge rles rles driv driv pe iod, iod, th deve develo lopm pmen en iv ns te no
00 hp ar bein bein
stem stems. s.
of ac slow slow spee spee ur dv nc in
hese hese earl earl sync synchr hron onou ou ha bl
de igns igns
potent potential ial manufa manufactu cturer rers. s. he need need fo extr extrem emel el
otor otor
io
or
th
cont contem empl plat ated ed ly
th or of liqu liquid id rheo rheost stat at or slip slip ecov ecover er it ound ound otor otor otor otors, s, load load-c -com ommu muta tate te inve invert rter er (LCl's), chin chines es or ge rles rles driv driv it cyc1 cyc1oc ocon onve ve ters ters have have allo allo ed or mill mill desi design gn it va iabl iabl sp eds. eds. ne
lt u at at i coor coordi dina nate te an
on ti
incl includ udes es full full-t -tim im
full full
high high qu lity lity gear gear is of para paramo moun un di il te
ng in pect pectio io
il
at th gear gear manu manu actu actu in
ig revi review ewed ed
P ap ap e I D 0 - 2 . a p pp pr ve th i ni ni n I nd nd us us tr tr y C o m itit te te e th IEEE IEEE Indu Indust stry ry Appl Applic icat atio ions ns Soci Societ et fo pres presen enta tati tion on at th 1989 1989 Indu Indust stry ry A pp pp lili c t i o ci ci et et y A nn nn ua ua l e et et i g , S a D ie ie g go o , C A O ct ct ob ob e 1-5. Manusc Manuscrip rip releas released ed for public publicati ation on Februa February ry 5, 1990. 1990. Th auth author or is at 4600 4600 Park Park Road Road Suit Suit 1000 1000 Char Charlo lott tte, e, NC 2820 28209. 9. IEEE IEEE Lo Numb Number er 9037 903706 062. 2.
kl
0093-9994/90/0900-0901$01.00
p at at t
il
1990 1990 IEEE IEEE
acil acil
902
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS VOL. 26 NO.5
in nd ng ll dr ve ar ic he in on interface, ha been invaluable in giving criteria fo specif in ge il ge ts III.
an mechanical sy te s. or constant spee followin system were evaluated:
he
ge le
i- ut ge us
iv
bl pe investigated Thes
li io include:
ound-rotor moto nd ot or
comple
applications
1990
th
ound roto moto it liquid rheo tats ua ti dr ve othe synchronou lo -speed driv sy te s.
GEARLESS DRIVE MECHANICAL INTERFAC
74
SEPTEMBER/OCTOBE
or
es
with liquid rheo tats ip ov
mechanical conditions on th mill an mill designer verter controls, ge le g)
or nt ng la +1 absolute runout of +0
ic
hi du in
ol an
in tallatio
an alignmen
va
te
mill electrical an
to
mechanical engineers.
he
nt
di
nt ge
em
il be eached
A. Fixed-Spee
System
Rheostats: nd ti
th
ou
dj
mill fo Codelc IV
nd
nd nt
ti
nt
ly
be pe
he
nd
oa
ut
to
[11.
io
os
hi
he
ot
os
du
ng
th
de ti
he
te
li it
to
te
h ro n u s to us of ir inherent stif torque versus th displacement angl characteristics discusse later. ound-rotor motors ar inductio machines with slip ings /am
roto io
qu
MECHANICAL CONSIDERATIONS
ur to io
th
to
at Chuquicamata
OTHE
ot
moto
follow
th
inductio
otor slip characte istics
in
ch
ct is
pe te
gi
th
va ie
th mill system V. ELECTRICAL DRIV
SYSTEM
ti
th po ig
qu
ls of op
at
ll
ow ha
or lo
GREER: SELECTIO
CRITERI
FO
SA
903
MILL DRIVES
ot
ou
to
to includin bearin ea an th po sibility of dust buildu in th otor area during operation. articula attentio should electrical alignmen hu idit bo
acto
at
os mine facilities th d-
pe i st i
un
or
fo synchronou
or
ot
it
qu
ts i sh e
to nt used or starting
ob ng li id o st a he greatest disadvantage of th
di on
lo
2) Synchronou ve
he
Moto
ly
uc
to
on is ound ro
te
Drives
hi
machines
or
or constant spee lo
to qu
ot
ap he
starting torque requirements an th po er line cu rent draw ti ou Th high-inrus
ta
di
nt
th
or ne ta nd on ot otor ca equire load starting torque from th
to
ti
to qu
in
ng it ic
l. hr no th ll he
ng
ge
0% os he ig to qu t- ol nt ti qu to ta ic nc th
ne
in in ho
hi
ll
th lo
ge ng
ic te
to
ot ou
he va
th
sa
approach
Siemens- llis ha used
cros -coupled stator
in xi ti ho
ir it
subjecte
of
to mo
ever
ge
stre se du in
ti
li
ju
th lo Th load imbalances that th moto
ui
depend on supplyin
is
he ow in us
ur over high-inrus on
equi ed
steady-state
In thei patented starting system
in lo
hr
ve
te
ou
de
motors
d at e oe
mall
ee du in
70 130%
id or
or
th starting process,
ti needed fo starting 3] Lo to qu otor design
nt
br
ty
h o p so n
tc
uadramatic ti
he
te
th
it
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS, VO
90
short-circui
damage.
in
B. Variable-Speed SA ls
Mill Driv System
hi un
li it
ou
ot
to
he
efficiency of th wound-roto
ta up
he ic
g. pa
il dr ve
de
th ha
te
u st r
pa
ha
d-
ound roto d-
motors ot
system it
studie
or th
di
us
liquid rheostat ip on
id of va in il drives
th om
pl
on he li id he ta
du in u at e
be
po
or
on
in he op ti
ot
ul to ht
ll
na
3) Slow-Spe le
he
th
hi
he
in
moto system particularly
qu
h a full
ge
di on
pi
om
ov
nd pe dng an pinion an associated losses
on
ar
to ot
ol
in
un ve
th
pe nc on it lo verters, gearless drives with cyc1oconverters. ov tate of-the ar
ng
iv
ne te he va iable- peed driv
op
iv he
om
to
ls il ba ic dy de da applications it some additional capita h av e b e
te
te
te
ix pe or variable spee
21i,NO.5. SEPTEMBER/OCTOBER 1990
if hi
Sync ronous
ri
na
is
yste s:
Without
de To to
ov
ni
th
hi
th othe variable-speed driv he th
pe
ti
qu
on
systems;
ng
ow in us
plifying th equipmen an ng
ds
is relativel
Th inve te
di
ot
ge
th li
required
maintenance-free.
ha tw
ajor disadvantage be
pe dng an pinion drive.
ir
th
or
force-commutated. ll
ha
GREER: SELECTIO
CRITERIA FO
SA
905
MILL DRIVES
om
to
ox
r/ he period it is orce co od
ut te
it
ts in th epar te po er supply field. tively si pl
[5
ve
io
ange el tively quickl
an us th breaka
te
characte isti anufacturing proces
an
in ulatin
techniques
equire
or
cascades. if
it 2ns
in th
bed.
ll
5) Othe Electrica Considerations: on
self-commutation problem. nt nn
ni
if if
io
of
All variable-speed
od
te
ti
ha
lo
na
ts
tt
id to
te be installe room
CI th otor ar inhe entl tied together an load sharin is provided ithout an proble
in lu in po itivel
housin
in
in
iq ventil te
building
electronics.
tively constant ti
ur be
ni
gn
t at i
n-
it poses.
hi
4) Gearless Drives oc io
be
da age.
n cl u tr
to
gn
owever
it cannot be overst es ed that th
nviron
and dirt-free VI.
ince th ea ly 1970 s. Th
equi ements an
lo
characteri tics la
equa basis.
di
A. Economic Evaluation hi
th
on
il manu actu er h av e
have addresse de
th gearless design il
Driv System
is
th in Tabl
Chile. he
ta
os
is
iv
ng
on is
906
IEEE TRANSACTIONS ON INDUSTRY APPLICATIONS VO
SA
M IL L
SYSTEM
D RI V
ECONOMIC
26 NO 5, SEPTEMBER/OCTOBE
COMPARISON
Fixed-Speed
Adjustable Spee Twin
Twi
Slow-Spee
Inductio
Synchronous Motor
Moto
with
Gearless
Synchronous
with
0.
oto
ende
0.
lead
94.5%
Overal efficienc
Wound-Roto
Inductio
wit LeI
Driv System
Liquid R~eostat
otor
nd
Overal power factor
l ea d
945%
1990
0.89 la
92.5%
92.2%
92.3%
93.1%
ende
Vendor
0.78 la
0.95 la
94.5/91.2%
K W L os se s a t 100
loa
521
C os t o f l os se s a t
$2 08 00
31
$4OOO/kW
C os t o f D ri v System
24 25
$175 0(
51 SH625
$1714500
$3923
100
$ 1] H
$4 38210
( XI I
T ot a c os t o f drive
system including 19
3 8 39 (
461
46
675
685
52
55 900
521
54
$5470000
t of m
$3165750
Cost of inchin drive
00
00
00
00
0 0
0 0
0 0
0 0
T ot a m il l a n driv
cost
LCI systems bCos o f
differ nc
08
$8635750
or l l l in e
be we
no
nd
n c u de d
il ve dors
re signific
nd di
ot
bl -s ee
th losses coincide with th standard depreciation allowanc or os pi equi en te at resent re resent he nd hi oper ting it norm ly ha rg influe ce
synchronou otor drive, An analysis of th adjustable-speed rive system indi te ha th twin w-sp sync ro us
op rati
fo th wound-ro
syst
is 86%, nd
rive is an bvious hoic
B, Maintenance, Reliability an Efficiency Evaluatio variable-speed driv system evaluate fo maintenance, reli ability, an efficiency This tabl represents th maintainabil it re ia ility, le rica ff ie nked orde wi
st
es
it
aria le-spe
ca bility se
op rate
variable-spee system, Base th ev lu ti
ro
in aina il ty
re ia ilit
GREER: SELECTIO
CRITERIA FO
SA
MILL DRIVES
90
MAINTENANCE,
RELIABILITY, AN
EFFICIENC
FACTOR
Maintenance Wound-roto
Comments
induction
88
High inrush
additional coolin fo liquid rheostatSynchronou possible starting p r b le ms , l es s t ha n o pt im u i m e da nc e f o
(91.0)
moto
consideration
DC
redundancy is present; torsional considerations no additional powe loss u nt es te d i n l a g e m il ls .
(91.5)
Gearless
1(92.3)
a tt ra ct iv e
flexing, moto r em a in s
e ch a i ca ll y
mo
a i g ap ,
sealin
u np ro ve n
transport logistics B ea ri n d es ig n n o optimized
yste
is elimin ted, il
ball mill
nd th cy loconverte
ha
om builti
an cement mill driv s. Fo overal variable-speed rl
efficiency. tandpoin ince no brushe re used in th driv in la reliabilit of mode electronic afte th infantil mortalit period (first thou an hour of operation) Th sy te houl
bein
preferre
give
applic tion an
ro motor. is
over th wound-roto iz th
ls th best conomi
C. Inchin
Driv System
rive houl fo
be in or or te
iv
lternative
maintenanc
rt it
ri
Th
ro
ri LCI.
line replacemen
into th
ystems Th reasonin
unless fail-safe
pe
co trol is av il
mad fail-safe
th second most efficien system
LCI
to driv unloaded provides an additional maintenanc factor into th system
reliabilit
ll
ic
change). ta
LCI
This also
as
VII.
ir
majo factor in th reliabilit
criteria asse se
CONCLUSION
bl fo larg mills. is obviou that th electrical engineer's re ponsibilit as ar of th mill design team is more involv f or e rs ri
moto ha high electric efficien y. Th wound-roto inductio moto with liquid rheo ta ha high maintenanc factor gained ov many ye rs Th bigges
is en ur
th
no prem ture failures occur.
908
IEEE TRANSACTIONS ON INDUSTRY APPUCATIONS, VOL. 26 NO
ho
of va at
he
o mi c
SEPTEMBER/OCTOBER
199U
in in il ty . S d eg r
i n l ec tr i a l
d on e g ra du at e w o electrical engineering.
election ca be made REFERENCES
2] [3]
S,
ro
a rg e
n du s r ia l
n gi n e ri n bu ne
p la n
f ro m h e U n
dm ni ra on
c en t a l p ow e
nd
pl nt
tions," Mining Eng., T ec hn i a l i t r a u re , ie en L.
s e i au to ge no u
ll ,"
p re s n t
supply systems,"
A.I.M.,
L ie g
at th
C ir e
E -A I
1 97 5
A nn u
e e i ng ,
ur en P re s d en t ing services. g i e re d
of Gr er
r of e i on a
As oc at
E ng in ee r i n h e
n d c on t n ue s
at
o f T ex a
p ro v d e
o n u lt -
