Z E S Z Y T Y N A U K O W E P O L IT E C H N IK I Ś L Ą S K IE J Seria: E L E K T R Y K A z. 139
1994 N r kol. 1247
Pavel B R A ND STETTER
V
VSB - T echnical U niversity O strava
VEC TO R C O N TR O L O F A SY N C H R O N O U S M O T O R W ITH SIG N A L PR O C E SSO R S u m m a ry . T h e p a p e r re fe rs to th e tw o -p ro c e ss o r c o n tro l sy stem w ith th e IN T E L 80 186 m ic ro p ro ce sso r and the T M S 3 2 0 10 d ig ita l sig n al p ro c e s s o r p ro v id ed a h ig h -sp e e d c o m p u tin g cap acity . T h e th eo ry o f th e v e c to r c o n tro l in th e field c o o rd in a te s o f a sy n ch ro n o u s m otor h as b e en su p p o rte d b y th e e x p erim e n ta l tests o f th e la b o ra to ry A C c o n tro l d riv e m odels. T h e u n iv ersal c o n tro l sy ste m on the b asis o f th e IN T E L 80 186 m ic ro p ro c e ss o r and the T M S 3 2 0 10 sig n a l p ro c e ss o r e n ab les to sim p lify th e c o n tro l c a lc u la tin g b lo ck s i f co m p ared to th e a n alo g v ersio n .
W E K TO R O W E STER O W A N IE SIL N IK A A SY N C H R O N IC Z N E G O ZA PO M O CĄ PR O C E SO R A SY G N A Ł O W E G O
S tre sz cz en ie . W p racy p rz e d sta w io n o p ro b le m a ty k ę w e k to ro w e g o ste ro w an ia siln ik ó w a sy n ch ro n iczn y ch , k tó re w p o łą c z e n iu z n o w o c ze sn y m falo w n ik iem n a p ię c ia p rz ed sta w ia p ersp ek ty w iczn y k ie ru n e k ro z w o ju re g u lo w a n y c h n a p ę d ó w elek try c z n y ch . B ad an ia ek sp ery m en taln e p rz ep ro w a d z o n e n a m o d elu la b o ra to ry jn y m p o tw ie rd z iły zało że n ia teo rety czn e ste ro w an ia w e k to ro w eg o . S y ste m s te ro w a n ia z rea liz o w a n o n a b azie m ik ro p ro ceso ra IN T E L 80 186 i p ro c e so ra s y g n a ło w e g o T M S 3 2 0 10.
V E K TO R R E G E L U N G D ER A SY N C H R O N M A SC H IN EN M IT D ER SIG N A L PR O Z E SSO R
Z u sa m m e n fa ss u n g . Im B e itra g w ird d ie P ro b le m a tik d e r V e k to rre g e lu n g d e r A sy n ch ro n m asch in en , d ie ste llt in V e rb in d u n g m it m o d e rn e n F re q u e n z u m ric h te rn eine P erspektive R ich tu n g in d e r E n tw ic k lu n g d e r e le k tris ch e n R e g e la n trie b e v o r, p rä sen tiert. D ie ex p erim en talen P rü fu n g e n a u f d e m L ab o rm o d e ll d e s D re h stro m re g e la n trie b s b e stätig te n d ie th eo retisch en G ru n d la g en d e r V e k to rrre g e lu n g d e r D re h stro m m a sc h in e n . D e r E in satz des en tw ick elten u n d re alis ierten M ik ro p ro z e ss o rste u e rsy s te m s a u f B asis d es M ik ro p ro z esso rs IN T E L 80 186 und S ig n a lp ro z e s so r T M S 3 2 0 10 e rm ö g lich te g ru n d sä tz lic h d ie R e ch e n b lo c k e gegen d ie a n a lo g e V e rsio n d e r V e k to rsteu e ru n g z u v erein fach en .
92 P. B ran d stetter
INTRO DU CTIO N
N e w c o n ce p tio n o f e le c tric a l c o n tro l d riv e s w a s in flu e n ce d b y th e d e v elo p m en t o f se m ic o n d u cto r c o m p o n e n ts w h ic h e n ab led th e d ev elo p m en t o f m o d e m se m ic o n d u cto r freq u en cy c o n v erters as th e p ra ctic a l re aliz a tio n o f m o d e m w ay s o f A .C . c o n tro l in clu d in g the co n tro l in the field c o o rd in a te s o f m o to r. T h e first a p p lic atio n s o f th e A .C . c o n tro l d riv es w ith in d u ctio n and s y n c h ro n o u s m o to rs w e re u sin g co n tro l sy stem s b ased o n th e a n alo g technique.
N o w ad ay s re la tiv e ly e ffic ie n t 1 6 -bits m ic ro p ro ce ss o rs can b e o b tain e d at the fo reig n m arket w h ic h m akes th e c h o ic e o f a sm all sa m p lin g p e rio d po ssib le, p e rm ittin g th u s th e e m p lo y m en t o f th e sam e m eth o d s in th e c o n tro l c irc u it d e sig n s as i f th e a n alo g c o n tro l c irc u its w e re used.
T h e ap p lic atio n s o f th e c o n tro l sy ste m s c o n ta in in g th e hig h e ffic ie n t m ic ro p ro c e ss o rs increase th e reliab ility o f the w h o le d riv e an d g et its se t-u p and sta rtin g c o m fo rtab le .
1. M athem atical description o f the asynchronous m otor
R esearch o f q u a lita tiv e ly n ew co n tro l m eth o d s o f A .C . m o to rs is b ased on the m ath em atical d esc rip tio n o f th e u n iv ersal m o to r w ith 3 -p h ase s ta to r an d ro to r w in d in g s. T his m o d el is su itab le fo r a lm o st all a p p lic atio n s w ith the su ffic ie n t accu racy . U sin g th e lim iting co n d itio n s for sta to r and ro to r v o lta g e eq u atio n s, this c an b e also u sed for th e d e sc rip tio n o f field -w in d in g sy n c h ro n o u s m o to rs o r p e rm a n en t-m a g n e t sy n c h ro n o u s m o to rs. T h e sim p lified m ath em atical d e sc rip tio n o f th e u n iv ersal A .C . m o to r m ay b e a c h iev e d by d e fin in g the co m p lex space v ecto rs. P o s itio n s o f th ese fo rm ally ad o p ted sy m b o ls d e fin e th e p o sitio n s o f th e m ax im u m v alu es o f stu d ie d q u a n tities.
C u rre n t sp ace v e cto rs (F ig. 1) in th e sta to r c o o rd in a te sy stem [a,b] an d ro to r c u rre n t space v e cto rs in the ro to r c o o rd in a te sy ste m [d,q] c an b e d e fin e d fo r th e a sy n c h ro n o u s m o to r, as follow s:
i si = ] ( i i a + i \ b a + i l e a 2 )
»2 = 3 O’la + i u a + h e d 2 )
w here:
a
=
ej2n/3
iin, i it>> < ic - in sta n ta n e o u s v alu es o f the p hase sta to r cu rre n ts
i 2 a , ¡
2
b , h e ~ in sta n ta n e o u s v alu es o f the phase ro to r c u rre n tsV ecto r c o n tro l. 93
S ta to r an d ro to r v o lta g e sp a c e v e cto rs can b e d e fin e d in th e sim ila r w ay:
I I I ~ 3 ( u l a + U \ b a + u i c a 2 ) u 2 = f (.112 a + U l b a + n 2 c a 2 )
I f th e w in d in g n o d e is n o t b ro u g h t aw ay , w e get:
i i a + i ib + i lc = 0 h a + h i ! + h e = 0
Fig. 1. S ta to r c u rre n t sp a c e v e cto r R y s .l. W e k to r p rz e strz e n n y p rą d u sto ja n a
T h e re al a x is o f th e s ta to r c o o rd in a te sy stem [ a , 3 ] is c o in c id e n t w ith th e a -p h ase axis o f w in d in g a n d th e s ta to r c u rre n t sp ac e v e c to r c an b e ex p ressed , as fo llo w s:
‘ I = i l a + y / 'i p
*
94 P .B ra n d ste tte r
T ran s fo rm a tio n fro m th e 3 -a x is [a ,b ,c] to 2 -ax is [a,|3] c o o rd in a te sy stem can be acc o m p lish e d u sin g th e e q u atio n s:
T h e in v erse tran s fo rm a tio n c a n b e e x p ressed by th e fo llo w in g equations:
1 0
1 y i
2 2 j
[!;;]=tr 2/si *[!;]
S y stem o f the d iffere n tia l e q u a tio n s c an b e d e riv e d b y m ean s o f th e sp ace v e cto rs, w hich d escrib e th e b e h av io u r o f th e a sy n c h ro n o u s m otor:
w here:
- re sistan c e o f o n e p h a s e o f s ta to r (ro to r) w in d in g , - to tal in d u cta n ce o f o n e p h a se o f s ta to r (ro to r) w inding, - m ain in d u cta n ce,
- m u tu al an g le b e tw e e n th e re al axes o f th e sta to r and ro to r c o o rd in a te sy stem , - a n g u la r ro to r speed,
- to tal m o m e n t o f in e rtia, - lo ad to rq u e.
V e cto r c o n tro l. 95
T o tal in d u ctan ces L s, L R c an b e e x p ressed u sin g th e m ain in d u cta n ce L h an d leak ag e c o efficie n ts Or, Os'-
Ls = ( l + O s ) L h
,
Ln = ( l + O R ) L h— Lsa — Ls 1 rr „ — - 5. _ 1
7 - I T " 1 - 1
T o ta l le a k ag e c o e ffic ie n t o :
_ i _ i ________ i
° LsLr (1+Oj)(I+Os )
As th e ro to r c u rre n t sp a c e v e c to r c an n o t oe m ea su re d w ith a c ag e m o to r, it is e lim in a te d by a stato r b ased m ag n e tis in g c u rre n t sp a c e v e cto r [Fig. 2.J, re p re se n tin g ro to r flu x [6J:
i l = ' ! \ f = i si + ( l + O R ) i R2 e *
T h e v o lta g e e q u a tio n s o f the a sy n c h ro n o u s m o to r can be e x p ress e d , as fo llo w s:
Rs
i'i +
o L s -j}- +(1 -
o ) L s -£■= .«i
R r i f + L h j , ( ¡ m e ~j E ) = 0
T h is re su lts in
r * ^ + ( W w » 7 * ) i £ = / i
O rie n tin g th e q u a n titie s fro m th e s ta to r c o o rd in a te sy ste m [ a ,P ] to th e sy ste m o f the o rie n te d co o rd in a te s [x,y] w h ic h is a lig n e d w ith th e m a g n e tis in g c u rre n t sp a c e v e c to r ira (resp.
ro to r flu x ) an d ro tates w ith th e a n g u la r v e lo c ity (oirn , w e g e t b y m an s o f th is eq u atio n
96 P .B ran d stetter w here:
- q u a n tity d e fin e d in the sy stem o f the o rie n ted c o o rd in a te s S O S [x,y], - q u a n tity d e fin e d to the s ta to r c o o rd in a te sy stem [ a , 3 ] S S S ,
- a n g le b e tw e e n th e real a x es o f th e SO S an d S S S sy stem s, th e fo llo w in g eq u atio n s:
d i° 0
Rs i i + o L s - ^ + j( o i„la L s i°l + (1 - o )L s d- f +yco„„(l - a )L si°n = u°
T « I T + M * T r i® + ( I - j 03m T K ) i°m =
F ig .2 . A n g u la r re la tio n s o f c u rre n t sp a ce v e cto rs R ys.2. Z ależn o ści k ą to w e w e k to ra p rzestrzen n eg o
T h e fo llo w in g eq u atio n s c an b e d e fin e d fo r th e sp a ce v e cto rs in th e sy stem o f th e o rien ted co o rd in a te s [x,y]:
i j = I l x " h j i l y , U i — W i x + y * K i y , i m — i / n x — i m
M o d ify in g th e p re ce d in g eq u atio n s, w e get th e sy stem o f eq u atio n s, w h ic h d escrib e b e h a v io u r o f a sy n c h ro n o u s m o to rs in th e sy stem o f th e o rie n ted c o o rd in a te s [x,y]:
V ector con tro l.. 97
OTs
+
i u = j f+
UunOTs 0 ) T s %s ~ ~ + i \ y = - jj- ~ (O im O T s i l x ~ ( 1 — C )(X )jm T s i m
C1J2 = CO 1 — CD,,, - — — I Iy I m l R
C = y + 5
2. M athem atical description o f frequency converter
A sy n ch ro n o u s m o to rs fo r th e lo w and m id d le p o w e r A .C . se rv o -d riv e s a p p lic atio n s are fed by in d ire ct freq u en cy c o n v e rte rs w ith a v o lta g e in te rm ed iate c irc u it. T h is ty p e o f freq u en cy co n v erter c o n sists o f a n o n -c o n tro lle d re c tifie r w ith a sm o o th in g filter and a b rid g e in v erter section. B asically , th e o u tp u t v o lta g e c an b e c o n tro lled b y th ese w ays:
a) p u lse -w id th m o d u la tio n an d its m o d ific atio n fo r th e h ig h e r h a rm o n ics e lim in a tio n - th is co n tro l is b ased on th e c o m p a ra tio n o f re fe re n c e and sin u so id a l vo ltag es,
b ) d ire c t v e c to r c o n tro l o f freq u e n c y c o n v e rte rs - th is c o n tro l is v e ry p e rsp e c tiv e at p resen t, nam ely for se rv o -d riv e s w ith h ig h d y n a m ic req u irem en ts.
S im p lifica tio n o f th e m ath e m a tic a l d e sc rip tio n o f in d ire ct fre q u e n c y c o n v e rte r w ith v o lta g e in te rm ed iate c irc u it m ay b e a ch iev e d i f w e su p p o se a co n sta n t in te rm ed iate c irc u it v o lta g e fo r th e d e sc rip tio n o f d y n a m ic b e h av io u r. T h is re q u ire m e n t is o ften m et b e c a u se o f an in te rm ed iate c irc u it c a p a c ito r b a tte ry c ap acitan c e.
T h e p h a se o u tp u t v o lta g e o f th e c o n v e rte r can b e e x p ressed b y th is eq u atio n :
w h e re Km g ain o f freq u e n c y c o n v e rte r, Tm tim e d e la y o f freq u en cy co n v erter. T h e g a in o f freq u e n c y c o n v e rte r can b e d e fin e d b y th is eq u atio n :
Mi a Km u s a ( t Tm )
98 P .B ran d stetter
w h e re k s c o n tro l c o e ffic ie n t o f freq u en cy c o n v erter (A-,= 3 /4 fo r sta n d a rd sin e-trian g le
co n tro l voltage.
T h e tim e d elay o f freq u e n c y c o n v e rte r can b e d e fin e d b y m ea n s o f th e sw itc h in g p erio d T s o f th e co n v erter:
A n a lo g ic ally , th e eq u atio n s fo r th e o th e r ph ase s can b e ex p ressed . U s in g th e sp ace vectors, w e g e t th e v o lta g e e q u atio n in th e s ta to r co o rd in a te system :
T h e fo llo w in g eq u atio n c an b e o b tain e d by v e c to r tra n s m ittin g into th e ro to r c o o rd in ate system :
3. Calculation o f m agnetising current m agnitude and orienting quntities
T h e m ag n e tisin g c u rre n t m a g n itu d e im and o rien tin g q u a n titie s siny, cosy can b e calcu lated b y th e fo llo w in g equ atio n s:
m o d u la tio n , A,=V3 / 2 fo r v e c to r c o n tro l), Umo in te rm ed iate c irc u it v o lta g e, U smlJ m axim um
ttf
= Km u s3 (t - Tm)
uRx= Kmu rs (t - T M) e ~ ^
u \
=
Kmu°s (t-
T u )<r>ra‘"r«
V ector co n tro l... 99
4. Speed control structure o f asynchronous m otor with vector control
P ro p o sal to th e sp e e d c o n tro l stru c tu re o f sy n c h ro n o u s m o to r is b a se d o n the m ath e m a tic al d escription o f a sy n c h ro n o u s m o to r an d fre q u e n c y c o n v erter. T h e cu rre n t c o n tro lle d stru c tu re consists o f th e p o w e r u n it o f freq u e n c y c o n v e rte r and a sy n c h ro n o u s m otor.
It c an b e seen in th e eq u atio n s o f th e a sy n c h ro n o u s m o to r, th at th e c o u p lin g b etw ee n the current v e c to r c o m p o n e n ts h as n o t b e e n c an celled . T h is co u p lin g m ay b e c a n c e lle d v e ry sim ply acc o rd in g to th e fo llo w in g e q u atio n s:
T h e first m em b e rs o f th e e q u a tio n s re p re se n t th e v o lta g e d ro p o f the re su ltin g reactan ce.
T he seco n d m em b e r o f th e se c o n d e q u a tio n re p re se n ts th e ro tatin g v o lta g e re su ltin g fro m ro tatin g o f a sy n c h ro n o u s m o to r ro to r.
T h e m u tu al c o u p lin y m ay b e c a n c e lle d b y ad d in g th e sig n a ls to th e o u tp u ts o f c u rre n t con tro llers. T h e c u rre n t c o n tro lle d stru c tu re c a n b e d e sc rib e d b y th e tra n s fe r fu n c tio n o f an inertial e le m en t w ith th e tim e c o n stan t
T h e co n tro l stru c tu re o f fre q u e n c y c o n v e rte r m ay b e d e sc rib e d b y th e eq u atio n s in c h ap 2.
I f w e ex p ress th is e q u atio n u sin g th e c o m p o n e n ts, w e get:
It c a n b e seen th a t th e re is a g a in m u tu a l c o u p lin g b e tw ee n axis c o n tro l v o lta g e s. T h e fo llo w in g c o n d itio n s m u st b e fu lfille d in o rd e r to c an c el th e m u tu al c o u p lin g b e tw e e n th e c o m p o n e n ts x,y:
tt rc — COjrn O L>s My
U y e = — [ t O¡» 1 O L s i l x + t 0 ,„ , ( 1 ~ O ) L s i , n ]
T , = o T s = a %
u\x = K M{t — T A,)[i/„cos (C 0;,„rM) + w.vySin (o},„, 7'm) \
u\y — Km(î —7'aî)[—MjxSin
{(ùimT M)+
UsyCos(to,m7A/)]
T , » Tm , toi m T M « 1
100 P. B ran d stetter
Fig.3. Speedcontro! structureofasynchronous motor with vector control Rys.3. Strukturawektorowej regulacjiprędkości silnikaasynchronicznego
V e cto r co n tro l. 101
I f th e c o n d itio n s a re n o t fu lfilled , it is n e ce ssa ry to c o m p e n sa te th e p h a se d isp lac em e n t w h ic h is c au s ed b y th e tim e d e la y o f freq u en cy c o n v erter. C o m p en s atio n m a y be a cc o m p lish e d by v e c to r tra n s m ittin g o f th e c u rre n t c o m p o n e n ts i t<x, iip in to th e c o o rd in a te sy stem [x,y] and th e v o lta g e c o m p o n e n ts u lx, u ,y in to th e sta to r c o o rd in a te sy ste m [ a ,P ] by m ean s o f th e re su ltin g fie ld -o rie n tin g angle:
Yv' “ Y "b COimr M
S im ilarly , th e p h a se e rro r c au s ed b y th e final c o m p u tin g sp ee d o f th e m ic ro c o m p u te r can b e co m p en sated . C o m p e n s a tio n c a n b e a c h iev e d b y ad d in g th e v alu e
T v =
1,5 7V
to th e tim e d e la y Tm, th e re T 0i is th e sa m p le p erio d o f the c u rre n t c o n tro l loop. T h e re su ltin g fie ld -o rie n tin g an g le c a n b e e x p ressed th en , as follow s:
Yv = y +
(oim (Tm+
T v)C a n ce llin g th e m u tu a l c o u p lin g b e tw e e n th e c o m p o n e n ts x ,y th e c o n tro l p a rt o f freq u en c y co n v erter w ill b e d e sc rib e d by th e tra n s fe r fu n ctio n o f an in ertial e le m en t w ith th e tim e c o n sta n t T M.
T h e final tran s fer fu n c tio n o f th e p o w e r and c o n tro l p a rts w ith c u rre n t tra n s d u c e rs w ith g ain Ki an d A /D c o n v e rte r w ith g a in Kad is g iv en b y th e final g ain KmKiKad/Rs, h ig h v alu e o f th e tim e co n stan t T i an d th e lo w v a lu e o f the tim e c o n sta n t Tnki. T h e PI c o n tro lle r can be d esig n ed fo r th is sy ste m u sin g th e o p tim u m -m o d u le m eth o d . T h is c o n tro lle r is d e sig n ed fo r th e se p a ra te c u rre n t c o m p o n e n ts in th e a x e s s,y.
T h e PI c o n tro lle r o f th e m a g n e tis in g c u rre n t (resp. ro to r flu x ) c an b e d e sig n e d fo r this sy stem u sin g th e o p tim u m -m o d u le m eth o d :
T d i m , . R dt lm ~ 1 lx
T h e re is a lso s u p e rio r sp e e d c o n tro lle r fo r th e c u rre n t lo o p in th e ax is y as in th e case o f th e D .C . sp eed c o n tro l d riv es. T h e sp e ed c o n tro ller c a n b e d e sig n e d b y th e sy m m e tric a l- o p tim u m m eth o d fo r th e tra n s fe r fu n c tio n en su ed fro m th e to rq u e e q u atio n an d th e tra n s fe r fu n ctio n o f th e c lo sed c u rre n t lo o p in th e a x is y.
102 P. B ran d stetter
T h e sp eed co n tro l stru c tu re o f th e a sy n c h ro n o u s m o to r w ith v e c to r c o n tro l in th e sy stem o f th e o rien ted c o o rd in a te s [x,y] is sh o w n in F ig .3 . T h e SW p a rt is so lv ed b y so ftw are and the H W p a rt d e te rm in e s th e n e ed e d h ard w are.
5. M icroprocessor control system
A d ju sta b le sp eed electric d riv es, p a rtic u la rly th e A .C . d riv es h av e the h ig h re q u ire m e n ts on a re sp o n se speed o f th e c o n tro l sy ste m and a c o m p u tin g cap a city in th e case o f the m ic ro p ro ce ss o r co n tro l system . H ig h c o m p u tin g d em an d s are g iv en e sp ecially by v ecto r c o m p u tin g o p e ratio n s, e x ten siv e c o m m u n ica tio n w ith p e rip h e rie s and e x ten siv e in terru p tio n sy ste m , w h ic h is n e ce ssa ry fo r a real tim e p ro cessin g .
T h e m ic ro p ro ce sso r-b ase d c o n tro l sy ste m c o n sists o f tw o p ro c esso rs -th e IN T E L 80 186 p ro c ess o r and th e T M S 3 2 0 10 sig n al pro cesso r. T h e b lo ck d iag ra m o f th e sy stem in cluding p e rip h e ra l c irc u its is sh o w n in F ig u re 4. T h e featu res o f th e p ro c esso rs m en tio n ed above d e te rm in e th e ir fu n ctio n s in th e m ic ro p ro ce ss o r system . B o th o f th e p ro cesso rs w o rk se p a ra tely th e ir m u tu al c o m m u n ic a tio n b ein g p ro v id ed by th e special c o m m u n ica tio n R A M . T h e p ro c ess o rs e x ec u te d iffe re n t so ftw a re tasks.
T h e b lo ck d iag ra m o f th e m ic ro c o n tro lle r w ith IN T E L 80 186 is sh o w n in F ig u re 5. T h e IN T E L 80 186 is 16 - b it ad v an ced m o d ific atio n o f the 80 8 6 m icro p ro cesso r. It is based on th e E x ec u tio n S u b p ro c e sso r U n it d esig n ed to ex ecu te in stru c tio n s an d th e B us In terface U nit p ro v id e d fo r se lec tin g in stru ctio n s, rea d in g o p eran d s and w ritin g resu lts. B o th o f th e units are re la tiv e ly in d ep e n d en t each o th e r an d th e ir fu n ctio n s m ay b e co v ere d . T o g e th e r th ey form the C e n tra l P ro c e sso r U n it. In ad d itio n , th e IN T E L 80 186 co n ta in s th e clo c k g e n erato r, the p ro g ra m m a b le in te rru p t c o n tro ller, th ree 16-bit co n tain s, p ro g ram m ab le D M A u n it and the p e rip h e ral ch ip -selec t logic. T h e IN T E L 80 186 its e lf co n ta in s th ese u se fu l c ircu its and so th ey n e ed n o t b e a d d ed as it is c o m m o n fo r th e m ajo rity o f o th e r p ro cesso rs. D irect m em o ry ad d ressin g cap a b ility is u p -to 1 M b y te w h ich is used fo r data, p ro g ram and stack. T h e re a d /w rite c y cle tim e m ay b e p ro lo n g ed w h en u sed th e lo w -sp e ed p e rip h ery .
T h e b lo c k d iag ra m o f th e m ic ro c o n tro lle r w ith T M S 3 2 0 10 is sh o w n in F ig u re 6. T h e T M S 3 2 0 10 m an u fa ctu re d b y T e x a s In stru m en ts w as th e first c o m m e rc ially su ccessfu l and w id e ly sp re ad sig n al p ro c esso r. T h is ty p e o f signal p ro c esso r w as se lec te d fo r A C d riv e c o n tro l sy stem d e v elo p m en t d u e to its re aso n ab le p rice an d also th an k s to en o u g h in fo rm atio n a b o u t it. T h e p ro c ess o r is m an u fa c tu re d b y N M O S tec h n o lo g y and in stru ctio n cy cle tim e is
V ector c o n tro l.. 103
200ns (m o st in stru ctio n s - in c lu d in g th e m u ltip lic a tio n - n eed o n ly o n e c y cle). T h e p ro c e ss o r provides 288 w o rd s R A M m e m o ry o n c h ip and 8 k B y te o f e x te rn al p ro g ra m m e m o ry can b e addressed. T h e d a ta len g th is 16-bit w ith in te rn al 3 2 -b it a cc u m u la to r.
T h e T M S 320 10 is a m o d e m a rc h ite c tu re 16-bit sig n al p ro c ess o r su p p o rte d b y 3 2 -b it arithm etic. H ig h -sp e ed in stru ctio n set is th e m ain a d v an tag e o f th e p ro c ess o r. In stru c tio n cycle len g th is 2 0 0 n s and m o s t o f th e in stru ctio n s in clu d in g m u ltip lic a tio n are p e rfo rm e d as one-cycle in stru ctio n s. H ig h sp e e d o f m u ltip lic a tio n o p e ratio n s is e n ab le d b y th e h a rd w a re m u ltip lier p lac ed rig h t o n th e p ro c e s s o r chip. O n th e o th e r sid e th e re a re so m e lim ita tio n s
- sm all size o f th e e x te rn al p ro g ra m m em o ry (4 k x 16 b its)
- sm a ll siz e o f th e in te rn al d a ta m em o ry p lac ed into tw o b a n k s (1 b a n k - 128 x 16 bits, 2 b a n k - 16 x 16 b its)
- sin g le in te rru p t in put
- sm a ll siz e o f th e sta ck ( 4 x 1 2 b its)
- d iffic u lt c o n n ec tio n s to th e lo w -sp e ed p erip h e rie s
T h e m ic ro c o m p u te r s tru c tu re is d e sig n e d w ith re sp ec t to c o m m u n ic a tio n w ith p a ra lle l o r m aste r co m p u te r. F o r re se a rc h re aso n s th e m ic ro c o m p u te r is p ro v id e d w ith th e h ig h -sp e ed R A M m em o ry fo r p ro g ram an d p ro g ra m is w ritte n to th is R A M by c o o p e ra tin g c o m p u ter.
W hole c o n tro l sy stem co n ta in s th e c o o p e ra tin g p ro c ess o r IN T E L 80 186 w ith its o w n R A M , E P R O M an d M U A R T w h ic h c o m m u n ica te s v ia serial p o rt w ith PC . T h is P C se rv es as an in te llig en t term in al. T h e IN T E L 80 186 p ro c e ss o r is also c o n n ec te d to th e A /D an d D /A co n v erters, sp e ed s e n so r an d o rie n ta tio n a n g le e stim ate c irc u it. C o o p e ra tin g p ro c e s s o r is also utilized fo r re c o rd in g o f tran s ie n ts d u rin g d riv e o p e ratio n .
S o ftw a re fo r th is c o n tro l sy ste m is d e sig n e d as m o d u la r b lo c k s w h e re each b lo ck rep re sen ts so m e c o m m o n u se d task as PI c o n tro lle r, axis tra n s fo rm a tio n e tc... T h is so lu tio n en ab les fast and c o m fo rta b le a sse m b ly o f c o n tro l p ro g ram a c c o rd in g to th e b lo c k d ia g ra m o f co n tro l stru c tu re . C o n tro l so ftw a re c o n sists o f tw o p ro g ram s. T h e first p ro g ra m is e x ec u te d by the IN T E L 80 186 p ro c esso r. T h is p ro g ra m p ro v id es c o m m u n ic a tio n o f c o n tro l sy ste m w ith o p e ra to r an d also p ro v id es in p u t d a ta ac q u isitio n and c o n tro l q u a n titie s o u tp u t fo r c o n tro l process. T h e se c o n d p ro g ram is e x ec u te d b y th e T M S 320 10 sig n al p ro c esso r. T h is p ro g ram p ro c ee d s all c o m p u ta tio n o f c o n tro l s tru c tu re a n d d u e to h ig h p e rfo rm a n c e o f th e T M S 320 10 p ro c ess o r a llo w s to a c h iev e sh o rt re p e a tin g p e rio d o f c o n tro l loops.
A /D c o n v e rte r b o a rd c o n sists o f e ig h t 12-bit c h an n e ls sa m p le d at th e sa m e tim e and tra n sfe rre d step b y step. R esu lt v a lu e is sto re d at th e F IF O m em o ries. S a m p lin g all ch an n e ls
104 P .B ran d stetter
at th e sam e tim e is v e ry im p o rta n t co n d itio n . U n fo rtu n ate ly it is not re a liz e d at all m an u fa ctu re d b o ard s. A ll c h a n n e ls h a v e th e c o m m o n sig n al g ro u n d and o n e b ip o la r voltage ra n g e ± 10 V. F o r th is re aso n all m e a su re d sig n als are g a lv a n ica lly se p a ra ted an d am plified in to ± 10 V level. It is p o ss ib le to m ea su re v a rio u s n u m b er o f channels. T ra n s fe r tim e o f one ch an n el is 16 ps. T h e A /D c o n v e rte r b o a rd is p lac ed in the IN T E L 80 186 m em o ry space. The re a d in g o f in d iv id u al m ea su re d c h a n n e ls p ro c e e d s fro m th e sam e ad d ress in th e se q u e n ce they h av e b een tran sferred . In itia liz a tio n an d sta rt-u p are a cco m p lish ed b y w ritin g th e com m and w o rd at n e x t addresses.
D /A c o n v e rte r b o a rd c o n sists o f e ig h t 12-bit c o n v e rters w ith th e b ip o la r ra n g e ± 10 V. The c o m m u n ica tio n b e tw ee n v a rio u s c h a n n e ls is v e ry fast sin ce th ey are rig h t in th e IN T E L 80 186 m em o ry space. T h e p o sitio n e v a lu a tin g b o a rd c o n sists o f 12-bit b id ire ctio n al co u n ter p ro v id e d to add o r su b s tra c t in v rem e n ta l c o d e r p u lse s acc o rd in g to th e sig n al phase. This b o a rd is p lac ed in th e IN T E L 8 0 186 m em o ry space.
F ig.4. C o n tro l sy ste m w ith m ic ro p ro c e s s o r 180 186 an d signal p ro c esso r T M S 3 2 0 10 R ys.4. D w u p ro ce so ro w y sy ste m ste ro w an ia z m ik ro p ro c eso rem 180 186 i p ro ceso rem
sy g n a ło w y m T M S 3 2 0 10
V e cto r c o n tro l. 105
T h e c o n n e c tin g m em o ry b o a rd is p lac ed in th e m e m o ry sp ace o f b o th p ro cesso rs. It is a sp ecial d u a l-p o rt R A M m em o ry , e n ab led to so lv e c o n te m p o ra ry accesses to th e m em o ry . I f th e m em o ry is n o t re a d y to a ccep t th e 80 186 p ro c e s s o r d ata, th e A R D Y in p u t is activ a ted to p ro lo n g re ad /w rite cy cle. I f th e m e m o ry is n o t re a d y to a cc ep t th e T M S 3 2 0 10 d ata, th e B IO in p u t is activ ated and teste d ju s t b e fo re w ritin g o r re ad in g . W h e n th e B IO in p u t is activ e the p ro c e ss o r is in th e w a itin g c o n d itio n .
T h e B S P b o a rd en ab les th e d riv in g o f p o w e r d riv e e le m e n ts th ro u g h th e o p to co u p le rs. T h e ad d ress is in th e T M S 3 2 0 10 I/O space.
T h e IN T E L 8 0 186 p ro g ram c an b e d iv id e d in to th ree b a sic tasks, th e task s are ex ecu te d a cc o rd in g to th eir p rio rity .T h e h ig h e s t p rio rity (i lev e l) p ro g ra m read s in p u t d a ta an d w rites o u tp u t q u a n titie s fo r th e c u rre n t c o n tro l lo o p p ro c ess ed b y th e T M S 3 2 0 10 p ro cesso r.
P ro g ra m w h ic h is p ro v id ed to re c o rd so m e im p o rta n t e x te rn a l and in te rn al v a lu e s into th e m em o ry w o rk s w ith th e sam e p rio rity .
F ig .5 . M ic ro c o n tro lle r w ith IN T E L 8 0 186
R y s.5 . S y ste m m ik ro p ro c e s o ro w y z u k ła d e m IN T E L 80 186
106 P. B ran d stetter
L o w e r p rio rity (II lev e l) p ro g ram e v alu ate s v e lo c ity fo r th e sp eed co n tro l loop. T h e low est p rio rity (III lev e l) p ro g ra m p ro v id es th e c o m m u n ica tio n w ith u se r and e n ab les th e desired v e lo c ity an d c o n tro lle r p a ra m e te rs a d ju stm en t. T h e c o m m u n ica tio n is p ro v id ed b y th e RS 232 se rial in te rfac e w ith term in a l u sin g A S C II codes. T h is p ro g ram is also p ro v id ed to d isplay actu al e x te rn al an d in te rv a l v a lu e s at a fo u r-ch a n n e l o sc illo sc o p e o r th ey can b e sen t through th e se rial p o rt to P C w h e re th e y c an b e pro cessed .
T h e a c c u ra te sta rt-u p o f p ro g ra m s is in su re d b y tw o IN T E L 80 186 in tern al tim e rs (TO and T 2 ). TO tim e r g e n e ra te s C P U in te rru p t a t th e in te rv a l o f 2 5 5 p s (it is th e sa m e fo r th e T M S 3 2 0 10 p ro c esso r). T 2 tim e r in terv al is d e te rm in e d by tw o fa cto rs - ty p e o f an increm ental en c o d e r an d v e lo c ity c a lcu la tin g m eth o d . T h e in crem en tal e n co d e r w ith 4 0 9 6 p u lses per re v o lu tio n an d T 2 tim e r in te rv al o f 5 m s h a s b een used.
T h e 8 0 186 p ro c e s s o r o f th is c o n tro l sy ste m is n o t fu lly used. It co u ld b e also u sed for actu al d riv e p a ram ete rs ad ju stm e n t d u rin g the o p eratio n . T h is p ro g ram m ay b e in co rp o rated in to II lev el o r III lev e l sy ste m o r it c an b e p ro c essed w ith th e p rio rity b etw een II and III.
T h is p ro g ra m m ay b e starte d b y th e a d d itio n al T1 tim e r th e p erio d o f w h ic h is d e riv e d from th e a d ju s tm e n t p ro g ra m alg o rith m .
F ig .6 . M ic ro c o n tro lle r w ith sig n a l p ro c ess o r T M S 3 2 0 10
R y s.6 . S y ste m m ik ro p ro c e s o ro w y z p ro c eso re m sy g n a ło w y m T M S 3 2 0 10
Vector co n tro l. 107
W hole p ro g ram in clu d in g th e T M S 3 2 0 10 p ro c e s s o r p ro g ram is tra n s fe rre d fro m the system to P C v ia a serial c o m m u n ic a tio n R S 2 3 2 in terface. B asis p ro g ram fo r sy stem initialization and serial lin e c o m m u n ic a tio n is in c o rp o ra te d into th e IN T E L 80 186 E P R O M m em ory. T h e T M S 320 10 p ro c e ss o r is p ro v id e d to c a lc u la te th e co n tro l s tru c tu re o f the drive. T h e p ro g ram c an b e ag ain d iv id e d in to 3 o r 4 b asic task s a cc o rd in g to th e e x te n t o f control stru ctu re. A s th e task s ca n n o t b e so lv e d b y th e p ro c e ss o r w ith o n e in te rru p t lev el at the sam e tim e, th ey a re p ro c essed a c c o rd in g to th e p rio rity d e fin e d b y so ftw are.
T h e h ig h es t p rio rity (I lev e l) p ro g ra m is u se d fo r th e P W M w ith c a rrie r freq u en cy o f 4 kHz. T h is p ro g ra m is in v o lv ed w h en th e v o lta g e so u rc e in v e rte r is used. M ed iu m p rio rity (II level) p ro g ram is p ro v id e d to c a lcu la te th e w h o le c o n tro l s tru c tu re e x ce p t th e v e lo c ity co n tro l loop. L o w e r p rio rity (III lev el) p ro g ram a llo w s to c a lc u la te th e v e lo c ity c o n tro l loop. T h e low est p rio rity (IV lev e l) p ro g ram se rv es fo r c o n tro lle r p a ra m e te rs re ca lc u latio n and c o m m u n icatio n w ith th e IN T E L 80 186 p ro c e ss o r. P a ra m e te rs m ay b e tran s ferre d at all program levels. T h e sta rt-u p tim es o f p ro g ram le v e ls a re 15 p s fo r th e I lev el, 255 p s fo r the II level, 5 m s fo r th e III level. W h o le p ro g ra m is tra n s ferre d to th e p ro g ra m m em o ry by m eans o f th e IN T E L 80 186 p ro cesso r. T h e p ro c e s s o r is c o n n ec te d to th e T M S 3 2 0 10 m em ory sp ace at th e T M S 320 10 re set c o n d itio n .
A ll m ath e m a tic al o p e ratio n s o f b o th p ro c ess o rs a re p ro c e e d e d at an in te g e r fo rm to insure the h ig h -sp e ed p ro cessin g . T h e p ro g ra m s a re w ritte n in th e form o f m acro in stru c tio n s. T h is m ethod p e rm its fast an d w ell-a rran g e d p ro g ra m m in g o f n e w stru c tu re s on th e b a se o f re ce n tly d eb u g g ed an d teste d m ac ro in stru c tio n s.
E X PERIM EN TA L RESU LTS
D e sc rib e d c o n tro l sy stem w as e x p e rim e n ta lly v e rifie d w ith in d u ctio n m o to r (P = 2 ,7 k W ) d riv e w ith v e c to r c o n tro l. E x p erim en tal re su lts c o n firm e x ce lle n t d y n a m ic b e h a v io u r o f the drive. T h e sa m e d y n a m ic p e rfo rm a n ce in a c c o rd a n c e to th e a n a lo g u e v e rsio n c an b e sh o w n at the d ig ita l c o n tro l sy stem b u t it h as e v e n all th e a d v an tag e s o f th e m ic ro p ro c e ss o r tech n iq u e a p p licatio n s (F ig .7 ,8 ). T h e m ain featu res o f th e re a liz e d A .C . c o n tro l d riv e are:
* fo u r-q u a d ra n t o p eratio n ,
* sp eed ra n g e (U Mo= 2 5 0 V )... -lOOOr.p.m.+lOOO r.p.m .
* flo atin g sp e e d u n d e r rev ersa tio n + 1 0 0 r.p .m . => -1 0 0 r.p .m . w ith o u t l o a d < 5 0 m s
108 P .B ran d stetter
F ig .7 . W av e fo rm o f q u a n titie s d u rin g sta rtin g and rev ersa tio n + /- 500 rp m R ys.7. P rzeb ieg i w y b ra n y ch w ie lk o ści ele k try c z n y c h i m e c h an ic z n y c h w czasie
ro z ru c h u i z m ia n y k ieru n k u w iro w a n ia + /- 5 0 0 o b r/m in
V e c to r c o n tro l. 109
F ig .8 . W av e fo rm o f q u a n titie s d u rin g sta rtin g an d re v e rsa tio n + /= 5 0 0 rp m R y s.8 . P rz e b ie g i w y b ra n y c h w ie lk o ści e le k try c z n y ch i m e c h a n ic z n y c h w cza sie
ro z ru c h u i z m ia n y k ie ru n k u w iro w a n ia + /- 5 0 0 o b r/m in .
110 P .B ra n d stette r
flo atin g sp eed w h ile u n lo a d in g M z > 5 0 % M„, and sp e ed n = 2 0 0 r.p .m .,,,, ..< 100 m s
* c o n tro lla b le a sy n c h ro n o u s m o to r to rq u e at tra n sie n t p ro c ess es b y sp eed co n tro lle r su p p ressio n .
C O N C LU SIO N
T h e p a p e r re fe rs to th e tw o -p ro c e ss o r co n tro l sy ste m w ith th e IN T E L 80 186 m ic ro p ro c e ss o r and th e T M S 3 2 0 10 d ig ital sig n al p ro c e ss o r p ro v id in g a h ig h -sp e ed c o m p u tin g cap acity . T h e th eo ry o f th e v e c to r co n tro l in th e v e c to r c o n tro l in th e field c o o rd in a te s o f a sy n c h ro n o u s m o to r has b e en su p p o rte d b y th e e x p erim e n tal tests o f the lab o ra to ry A C c o n tro l d riv e m o d els. T h e u n iv ersal co n tro l sy stem o n th e b asis o f th e IN T E L 80 186 m ic ro p ro c e ss o r and th e T M S 320 10 sig n al p ro c e ss o r en ab les to sim p lify th e co n tro l c a lcu la tin g b lo c k s i f c o m p a red to th e a n alo g v ersion. M o re o v er it sh o u ld m ak e th e ad ap tiv e and o p tim u m d riv e c o n tro l p o ssible.
R EFE REN C ES
1. B ra n d stetter P.: M o d e m W ay s o f S y n ch ro n o u s M o to rs C o n tro l, H a b ilitatio n w ork, O s tra v a 1991, p .95.
2. B ra n d ste tte r P ., C e rm a k T ., C h leb is P., K o z in a J., S te fan ik M .: M ic ro c o m p u te r S y stem C o n tro l in F ie ld C o o rd in a te s o f S y n c h ro n o u s M achine. In.: E C E 91 - 4 th E u ro p ean C o n fe re n c e o n P o w e r E le k tro n ic s an d A p p licatio n s. F ire n ze 1991, Italy , s.5 6 0 -5 6 5 . 3. B ra n d ste tte r P., Florak T ., C h leb is P ., M e c h M ., S te fa n ik M .: M ic ro p ro c e sso r - based
C o n tro l S y ste m w ith T M S 3 2 0 10 S ig n al P ro c e sso r fo r A C C o n tro lle d D rives A p p lica tio n s. In: IS P S ’ 92 - In te rn a tio n a l S e m in a r o n P o w e r S e m ic o n d u c to r. P ra h a 1992.
4. B ra n d stetter P ., C h leb is P ., M ech M ., S te fan ik M .: A p p lic a tio n o f S ig n al P ro c e sso r in A C D riv es. In: E D & P E 92 - In tern a tio n a l C o n fe ren c e o n E le ctrica l D riv e s and P o w er E le ctro n ics. K o s ic e 1992, s.7 8 -8 1 .
V ecto r control. I l l
5. B ra n d stetter P.: V e c to r C o n tro l o f S y n c h ro n o u s M ac h in e w ith C y c lo c o n v erte r. In: V S y m p o zju m P P E 93 - P o d s ta w o w e P ro b le m y E n erg o e le k tro n ik i. G liw ic e -U stro ń 1993.
6. L eo n h a rd W .: C o n tro l o f E le c tric a l D riv es. S p rin g e r V e rla g B e rlin -H e id e lb e rg 1985.
R ecenzent: D r h ab .in ż. E u g e n iu sz K ału ża W p ły n ęło d o R e d ak c ji 12 m a ja 1993 r.
Skrót
W p ierw szej czę śc i p ra c y p rz e d sta w io n o o p is m a te m a ty c z n y d y n a m ik i siln ik a a sy n ch ro n iczn eg o z as ilan e g o z fa lo w n ik a n a p ię c ia o p iera ją c się n a z d e fin io w an y c h w e k to rac h przestrzen n y c h p rą d u sto jan a i w irn ik a (rys. 1). D la w y s zc ze g ó ln io n e g o u k ład u n a p ęd o w e g o op raco w an o stru k tu rę w e k to ro w ej reg u la cji p rę d k o ści o b ro to w ej siln ik a (ry s.3 ). D ru g a część p racy (p k t 5 i 6 ) z aw ie ra o p is z re a liz o w a n eg o sy stem u w ek to ro w ej re g u la cji p rę d k o ści siln ik a oraz w y n ik i b ad ań e k sp e ry m e n ta ln y ch p rz ep ro w a d z o n y ch n a m o d elu lab o ra to ry jn y m o b ejm u jący m u k ład n a p ę d o w y z e s ta w io n y z falo w n ik a n a p ię c ia o ra z siln ik a asy n ch ro n iczn eg o o m o cy 2 ,7 k W o b c ią ż o n e g o siln ik ie m o b c o w z b u d n y m p rą d u stałego.
R eg u lację p rę d k o ści o b ro to w e j s iln ik a asy n c h ro n ic zn e g o z rea liz o w a n o za p o m o cą d w u p ro ceso ro w eg o s y te m u ste ro w an ia z m ik ro p ro c es o re m IN T E L 80 186 o ra z p ro c eso re m sy g n ało w y m T M S 3 2 0 10 (ry s .4). O b y d w a p ro c eso ry p ra c u ją a u to n o m ic z n ie i z g o d n ie z o p ro g ram o w a n iem re a liz u ją o d d z ie ln e zad an ia. W za je m n a k o m u n ik a c ja p o m ię d z y pro ceso ram i p rz e b ie g a p o p rz e z p a m ię ć R A M . W łasn o ści d y n a m ic z n e la b o ra to ry jn e g o m o d elu układu n ap ęd o w e g o p rą d u p rz em ie n n e g o z m ik ro p ro c e s o ro w y m sy s te m em ste ro w an ia ilu stru ją p rz eb ieg i w ie lk o ści e le k try c z n y c h i m ec h an ic zn y c h w c z a sie ro z ru c h u s iln ik a o ra z zm iany k ieru n k u w iro w a n ia p rz e d sta w io n e n a rys. 7 i 8.
