Gt Sua Chua Dong Co Dien _bom Dien

8/10/2019 Gt Sua Chua Dong Co Dien _bom Dien

1/95

B NNG NGHIP V PHT TRIN NNG THNTRNG CAO NG NGH C IN H NI

-----------------------------------------------------------------------

GIO TRNH

A CHA NG C INHNG NG B

(TI LIU LU HNH NI B)


2/95

TUYN B BN QUYN

-Ti liu ny thuc loi sch gio trnh, cho nn cc ngun thng tin c

th c php dng nguyn bn hoc trch dng cho cc mc ch v o to vtham kho.

- Mi mc ch khc c lch lc hoc s dng vi mc ch kinh

doanh thiu lnh mnh s b nghim cm.

a ch lin h :Trng Cao ng ngh C in H Ni 160 Mai Dch

Cu Giy H Ni.


3/95

LI NI U

Hin nay trn t nc ta ang h tr v m rng dy ngh v o tongh cho cc khu vc nng thn, vic p dng cc tin b khoa hc k thut vo

qu trnh sn xut ang c nh nc v cc ban nghnh ch trng thc hin. ngi hc c c kin thc k nng v qun l v sa cha bm in lnhvc t ng ho trong sn xut nng nghip v cng nghip th vic tip cn lthuyt c bn, k nng thc hnh i vi ngi hc l iu cn thit.

Chnh v vy Gio trnh c vit vi mc ch phc v cho o to k thut vin ngh sa cha bmin, cng nh lm ti liu cho sinh vin chuyn ngnh tham kho.

rn c s chng trnh khung ca ng ghip v , nhm tc

gi t chc bin son chng trnh ny mt cch khoa hc, h thng v cpnht nhng kin thc thc tin vi i tng hc sinh. io trnh c vit gmcc bi:

1: . 2: V dy q 3: To lp 4: dy v 5: S t p 6: S ba pha.

Ti liu ny c thit k theo tng m un thuc h thng m uncamt chng trnh, o to hon chnh.c dng lm gio trnhcho ngi hc cc kha o tongn hn

hoc cho cc cng nhn k thut, cc nh qun l v ngi s dng nhn lctham kho.

io trnh c vit n gin, d hiu ph hp vi i tng o to.rong qu trnh vit gio trnh, mc d c nhiu c gng nhng trnh khinhng thiu st. Chng ti rt mong nhn c nhng kin ng gp ca bnc gio trnh ti bn ln sau tt hn.

Mi kin xin gi v Khoa in trng Cao ng ngh C in H ni,s 160 Mai dch, Cu iy, H i.

Xin chn thnh cm n.

CC TC GI


4/95

Mc Lc MC TRANG

TUYN N QUYN................................................................................... 2

LI NI U...................................................................................................... 3

M L................................................................................................................ 4

V tr, , v tr .............................................................................. 7

M UN: SA CH N INN N ....................... 8

1: ............................................................................ 8

1.1. v ............................................... 8

1.2. to p....................................................... 8

1.2.1. Cu to..................................................................................................... 8

1.3. Ny l l v ............................. 9

1.4. M y p.................................................... 11

1.4.1. Qu trnh m my ng cin khng ng b:................................. 11

1.4.2. Cc phng php m my.................................................................... 11

1.4.2.2.M my gin tip ng crotor lng sc:.................................... 12

1.5. t p................................................................ 14

1.5.1. i cng............................................................................................. 14

1.5.2.Nguyn l lm vic................................................................................ 14

1.5.3. Phng php m my v cc loi ng cin mt pha..................... 16

1.5.3.1. Cc phng php m my:............................................................ 16

1.5.3.2. hn loi:....................................................................................... 17

1.5.3.3. S dng ng cin 3 pha vo li in 1 pha:......................... 17

1.6.S dy q ..................................................... 18

1.6.1. S dy qun ng ckhng ng b ba pha................................... 18

1.6.2. S dy qun ng ckhng ng b mt pha................................. 20

B 2: V dy q ..................................................................... 21

1. v dy q....................................................................... 21

1.1.Nhim v.................................................................................................. 21

1.2. Cc yu cu k thut............................................................................... 21

1.3. Phn loi dy qun.................................................................................. 21

2. N v dy q............................................................... 21

2.1. Bi dy. .................................................................................................... 21


5/95

2.2. Cnh tc dng........................................................................................... 22

2.3. u ni bi dy....................................................................................... 22

2.4. Bc dy qun......................................................................................... 23

2.5. Nhm bi dy (nhm phn t)................................................................. 23

2.6. Bc cc. ................................................................................................. 242.7. Gc lch pha gia hai rnh lin tip......................................................... 24

2.8. Dy qun mt lp, dy qun hai lp........................................................ 24

2.9. S phn chia nhm bi dy ca mt pha................................................ 24

3. Ph pp v dy q ( tr) tto ba pha; ................................................................................................................ 25

3.1. Dy qun mt lp..................................................................................... 25

3.2. Dy qun hai lp...................................................................................... 28

4. Dy q tto t p......................................... 29

4.1. Dy qun mt lp..................................................................................... 29

4.2. Dy qun hai lp...................................................................................... 35

3: To lp ............................................................................. 40

1. Tr t to .................................................................................... 40

2. L ng c........................................................................................... 43

3. tr t qt t tr ; ........................................................ 43

3.1. Xem xt v my....................................................................................... 43

3.2. Kim tra rto ............................................................................................ 43

3.3. Kim tra vng bi (bc )........................................................................ 44

3.4. Kim tra stato........................................................................................... 44

4. Lp .................................................................................................... 45

5. tr o tt............................................................................................ 45

4: dy v ............................................................. 46

1. l tr y........................................................... 46

2. tr dy r tr p ........................................................ 48

2.1. Quy c k hiu u Cui.................................................................. 48

2.2. Quy cch b tr cc mi dy ra trn hp ni............................................ 51

3. dy v ............................................................................ 52

3.1. Kim tra ng ctrc khi vn hnh...................................................... 52

3.2. Vn hnh ng c .................................................................................... 53

4. tr d t........................................................................ 54


6/95

5: S t p........................................... 55

1. Q dy t p (My m n, y )........................... 55

1.1. To v v .............................................................................. 55

1.2. S tri b dy qun.............................................................................. 55

1.3. Thu thp cc s liu cn thit................................................................... 551.4. Thi cng qun dy.................................................................................... 56

1.4.1 Lt cch in rnh stato ng c....................................................... 56

1.4.2. Qun (hay nh) cc bi dy cho mt pha dy qun....................... 59

1.4.3. Lng dy vo rnh stato.................................................................... 61

1.4.4. Lt cch in u ni, hn dy ra v ai gi u ni...................... 66

1.5. Th nghim. ............................................................................................. 69

2. Cc pan h v pp p.................................................... 69 6: S p............................................. 72

1. To v v . ................................................................................ 72

2. o t v v l dy q.................................................................. 73

2.1. Xc nh cc s liu ban u.................................................................... 73

2.2. Tnh ton sliu ..................................................................................... 73

3. Thi q dy.......................................................................................... 78

3.1. Lt cch in rnh stato ng c............................................................. 783.2. Qun (hay nh) cc bi dy cho mt pha dy qun.............................. 81

3.3. Lng dy vo rnh stato.......................................................................... 83

3.4. Lt cch in u ni, hn dy ra v ai gi u ni.............................. 89

4. Lp rp v v t................................................................................ 92

5. Cc pan h v pp p.................................................... 93


7/95

V tr, ngha, vai tr m un

Vi mc tiu phc v cho qu trnh sn xutt, kinh doanh, mi sinh hot chocon ngi v x hi. ng c in l mt thit b in khng th thiu trong

sinh hot cng nh sn xut. rong qu trnh lm vic khng th trnh cnhng h hng khng ng c, chnh v vy cng vic bo dng v sa cha lmt vic ht sc quan trng i vi ng c in.

Cng vic sa cha ng c in i hi ngi lao ng phi c kin thc cbn v ng c in, c nhng k nng qun, lng dy v u ni thnh tho,chnh xc. Cng vic sa cha gn lin vi s t duy v nhn nh chnh xccc h hng t c c cc phng php nhanh nht v hu ch cho vic

sa cha.

Mc tiu:- rnh by c cu to, nguyn l ca cc loi ng c khng ng b

thng dng-hn loi c cc loi ng c khng ng b 1 pha, 3 pha.- ho lp, u ni thnh tho ng c 1 pha, 3 pha thng dng.-Ly mu cc b dy ng c khng ng b chnh xc.- V c s tri cc b dy theo mu.- Qun c cc b dy ng c khng ng b.- Sa cha c cc h hng ca ng c khng ng b.

-Rn luyn tc phong cng nghip, an ton cho ngi v thit b.

hc m un ny c hiu qu gio vin nn cho hc sinh hc tp theotng nhm hoc c lp t hnh thnh nn k nng cho hc sinh.

hng php nh gi kt qu ca hc sinh c nh gi tch hp gia lthuyt v thc hnh.


8/95

M UN A CHA NG C IN

HNG NG B

Bi 1: ng c khng ng b

1.1. hi nim chung v ng c khng ng b.My in khng ng b l my in xoay chiu, lm vic theo nguyn l

cm ng in t, c tc quay rotor n (tc quay ca my) khc vi tc quay ca t trng 1n .

My in khng ng b c hai dy qun stator (s cp) ni vi li intn s f = const, dy qun rotor (th cp) c ni tt li hoc khp kn qua intr. Dng in trong dy qun rto c sinh ra nh sc in ng cm ng ctn s 2f ph thuc vo tc rto ngha l ph thuc vo ti trn trc ca my.My in khng ng b c tnh thun nghch, ngha l lm vic 2 ch ng c v my pht.

Hnh 1.1 Stator ca my in khng ng b

1. V my

2. Li thp

3. Dy qun

1.2. Cu to ng c khng ng b ba pha.

1.2.1. to. P t ( ttor):Gm c v my li st v dy qun

- V my: c nh li st v dy qun khng dng lm mch dn t.Thng lm bng gang hay thp tm hn li.


9/95

- Li thp t: L phn dn t, lm bng thp l k thut in dy 0,35 mmhay 0,5mm p li. Khi ng knh ngoi li thp Dn< 990 mm th dng nhng

tm trn p li. Khi Dn> 990 mm th dng nhng tm hnh r qut ghp li

thnh khi trn. Mt trong cathp c x rnh t dy qun.- Dy qun: Dy qun ca stator c t vo cc rnh ca li thp v

cch in tt i vi rnh.. P qy ( rotor): l tp v dy q

- Li thp: Dng thp k thut in nh stator, li st c p ln trcquay, pha ngoi c x rnh t dy qun

- Dy qun: C hai loi:Loi rotor kiu lng sc: Cu to ca loi dy qun ny khc vi dy qun

stator. Trong mi rnh ca stator t vo thanh dn bng ng hoc bng nhmdi ra khi li st v c ni tt hai u bng hai vnh ngn mch bng nghoc bng nhm m ngi ta thng quen gi l lng sc hnh 1.2.

. e :Khe h trong my in khng ng b rt nh (t 0,2 n 1 mmtrong my in c nh v va), cng nh cng tt hn ch dng t ha ly tli in vo.

Hnh 1.2 Rotor lng sc ng c in khng ng b.

1.3. Nguyn l lm vic c bn ca ng c khng ng b.My in khng ng b l loi my in lm vic theo nguyn l cm

ng in t. Khi cho mt dng in ba pha i vo dy qun ba pha t trong list stator th trong my sinh ra mt t trng quay vi tc ng b n 1 =

60f/p, f l tn s li in a vo f = 50 Hz, p l s i cc ca my. T trngny qut qua dy qun nhiu pha t ngn mch t trnli st rotor v cm ngtrong sc in ng v dng in. T thng do dng in ny sinh ra hp vi

t thng ca stator to thnh t trng tng khe h . Dng in trong dyqun ca rotor tc dng vi t thng ny sinh ra mmen. Tc dng ca n cquan h mt thit vi tc quay n ca rotor, vi nhng phm vi tc khcnhau th ch lm vic ca my cng khc nhau. ch phm vi tc cami my, ngi ta dng h s trt s. Theo nh ngha h s trt bng:

1001

1%n

nns

Nh vy th: n = n1s = 0; n = 0 s = 1

n > n1s < 0; n < 0 s > 1 (rotor quay ngc chiu t trng quay). Tr p rotor qy t v t tr qy < 1 (0 < s < 1


10/95

Gi s chiu quay n1 ca v chiu quay n ca rotor nh hnh 1.6. Do

n < n1nn chiu chuyn ng ca thanh dn suy ra chiu E, Ic xc nh

bng qui tc bn tay phi. I tc dng vi sinh ra F, M c chiu xc nh

bng qui tc bn tay tri, M lm rotor quay theo chiu ca t trng vi n


11/95

1.4. M my ng c khng ng b ba pha.

1.4.1. Qu trnh m my ng c in khng ng bQu trnh m my ca ng c l qu trnh atc ng c t khi n

tng th phng trnh cn bng ng v moment nh sau:

dtdJjMcMM

Trong :M, Mc, Mj: moment in t ca ng c, moment cn, moment

qun tnh.

49

2.DGJ : hng s qun tnh

g = 9,81m/ 2s : gia tc trng trngG: trng trng phn quay

D: ng knh phn quay: tc gc ca rotor

tc ca ng c tng thun li th 0dt

dcMM

Khi bt u m my s = 1:

mI

nxRR

phaUmmI )74(

2221

1

Trn thc t, mch t tn ca my bo ha nhanh X gim mmI cn ln hnnhiu so vi tr s tnh theo cng thc trn.

1.4.2. Cc phng php m myCc yu cu khi m my:- Mmmphi ln thch ng vi c tnh c ca ti.

- Immcng nh cng tt.

- Phng php m my v cc thit b cn dng n gin, r tin v chcchn.

- Tn hao cng sut trong qu trnh m my t.1.4.2.1. M y tr tp rotor l :


12/95

a. hng php h in p mmy:Ch p dng vi cc thit b yucu moment m my nh.Dng in m my ln, ch dng cho

cc my c cng sut nh. Nu my c

cng sut ln th dng trong li inc cng sut ln. Phng php ny mmy nhanh, n gin.

L1

3~

F1

K1

F2

1

2

3

4

5

6

L2

L3

N

PE

1.4.2.2.M y tp rotor l :b. Dng cun khng bo ha trongmch statorKhi m my ng D1, D2m:M my xong ng D2

- Lc m my trc tip:

nZ

mU

nxnR

mUmmI

22

1

/2

21

rmmlm

mmM

- Lc m my c cun khng(in khng xk):

22

kx

nx

nR

mUmmkI

2

D 1

D

1

/2

21

rmmklm

mmkM

T , ta c:

1

22

22

k

xxR

xR

I

I

knn

nn

mm

mmk

2

22

22k

kxnxnR

nxnR

mmM

mmkM


13/95


14/95

Nh vy, khi m my bng bin p t ngu dng in trong li gim i k2lnso vi Immkhi ni trc tip.

1.5. ng c khng ng b mt pha

1.5.1.

Hnh 1.7. ng c khng ng b 1 phang c khng ng b mt pha thng c dng trong cc dng c

sinh hot v cng nghip, cng sut t vi watt n khong vi nghn watt v nivo li in xoay chiu mt pha. Do nguyn l m my khc nhau v yu cutnh nng khc nhau m xut hin nhng kt cu khc nhau, nhng ni cho cngvn c kt cu c bn ging nh ng c in ba pha, ch khc l trn stator chai dy qun: Dy qun chnh hay dy qun lm vic v dy qun ph hay dy

qun m my. Rotor thng l lng sc. Dy qun chnh c ni vo li introng sut qu trnh lm vic, cn dy qun ph thng ch ni vo khi m my.Trong qu trnh m my, khi tc t n 75 n 80% tc ng b th dngngt in kiu ly tm ct dy qun ph ra khi li. C loi ng c sau khi mmy, dy qun ph vn ni vo li. l ng c in mt pha kiu in dung(hay cn gi l ng c in mt pha chy t).

1.5.2.Ny l l vu tin, ta xt ch lm vic ca ng c in mt pha khi dy qun

m my ngt ra khi li. Dy qun lm vic ni vi in p mt pha, dngin trong dy qun s sinh ra t trng pmch . T trng ny c th phntch thnh hai t trng quay A v B c chiu ngc nhau, c nA= nBv

bin bng 1/2 bin t trng pmch (hnh 1.8 a).


15/95

Hnh 1.8. Nguyn l lm vic ca ng c in khng ng b mt pha

Nh vy, c th xem ng c in mt pha tng ng nh 2 ng c in bapha ging nhau c rotor t trn cng mt trc v dy qun stator ni ni tipnhau sao cho t trng ca chng sinh ra trong khng gian theo chiu ngc

nhau (hnh1.8b). n lt chng li tng ng mt ng c in ba pha chai dy qun ni ni tip nhau to ra A v B (hnh 1.8 c). Trong ng cin mt pha cng nh trong hai m hnh ca chng, t trng quay thun vnghch tc dng vi dng in rotor do chng sinh ra to thnh hai moment MA

v MB. Khi ng c ng yn (s = 1) th MA= MBv ngc chiu nhau, do

moment tng M = MA+ MB= 0. ng c khng quay c ngay c khi khng

c MCtrn trc.

Nu quay rotor ca ng c in theo mt chiu no (v d quay theo chiu

quay ca t trng dy qun A nh hnh 1.8 b) vi tc n th tn s ca s..,dng in cm ng rotor do t trng quay thun A sinh ra s l:

1160

)1(1

60

)1(2 sf

n

nnpnnnpAf

Cn i vi t trng quay ngc B th tn s y l:

Hnh 1.9. c tnhM = f(s) ca ng c in khng ng b 1 pha

1)2(1

)1(12

60

1

60

)1(2 fs

n

nnnpnnnpBf

y (2 - s) l h s trt ca rotor i vi t trng B .Cho rng M > 0 khichng tc dng theo chiu quay ca t trng

A , ta s c cc dngng cong

MAv MBnh hnh 1.9:


16/95

Khi s = 1 th M = 0, ng c khng th bt u quay c khi trn stator ch cmt dy qun v iu kin lm vic ca ng c khi rotor quay theo chiu nyhoc chiu kia vi tc n u ging nhau (v ng c tnh mo ment c tnhcht i xng qua gc ta ).

1.5.3. hng php m my v cc loi ng c in mt pha1.5.3.1. Cc phng php m my:a. Dng dy qun ph:

Nh chng ta bit, nu ch c dy qun chnh ni vo li in th ttrng trong dy qun mt pha l t trng p mch, nn ng c in khngng b mt pha khng th t m my c v khi s = 1 th M = 0.Mun ng c t m my (khi ng) th t trng trong my phi l t trngquay hoc t nht t trng quay ngc phi yu hn so vi t trng quaythun A , to ra t trng quay c th dng vng ngn mch hoc dy qun

ph v phn t m my. Dy qun ph t lch pha so vi dy qun chnh mtgc 900 trong khng gian trn mch t stator; phn t m my dng dng tos lch pha v thi gian gia dng in trong dy qun chnh v dy qun phc th l in tr, cun dy hoc t in, t in c dng ph bin v dng tng c c m men m my ln, h s cng sut coscao v dng in mmy tng i nh.

- Dng in tr m my: lm cho Immlch pha so vi Ilvngi ta ni thm mt in tr hay

in cm vo cun dy m my. Mmm

ca loi ng c ny tng i nh.

Trong thc t ch cn tnh ton sao cho bn thn dy qun ph c in tr tngi lnl c (dng bi dy chp ngc) khng cn ni thm in tr ngoi.

-Dng t in m my:Ni t in vo dy qun m my ta c kt qu tt hn. C th chn tr

s t in sao cho khi s = 1 th Immlch pha so vi Ilv900 v dng in ca cc

dy qun c tr s sao cho t trng do chng sinh ra bng nhau. Nh vy khikhi ng ng c s cho mt t trng quay trn.ng c in mt pha kiu in dung:

Ta c th nguyn dy qun m my c t in ni vo li in khing c lm vic. Nhvy ng c in c coi nh ng c in hai pha.Loi ny c c tnh lm vic tt, nng lc qu ti ln, h s cng sut ca myc ci thin. Nhng tr s in dung c li nht cho


17/95

m my li thng qu ln i vi ch lm vic, v th trong mt s trnghp khi m my kt thc phi ct bt tr s ca t in ra bng cng tc ly tm.b. Dng vng ngn mch:

Vng ngn mch F ng vai tr cun dy ph F qung 1/3 cc t. Khi tmt in p vo cun dy chnh m my, dy qun s sinh ra mt t trngp mch c . Mt phn ca c l c' s i qua F v sinh ra In trong F

( nnI ), nu b qua tn hao trong vng ngn mch th n s trng phng viIn. n tc dng vi c' sinh ra f=n+clch pha so vi phn t thng cn

li cc ' . Do , s sinh ra mt t trng gn ging t trng quay v chomt moment m my ng k.

Hnh1.10. ng c inmt pha c vng ngn mch

1.5.3.2. P lo:ng c in mt pha c th phn lm cc loi sau:

- ng c in mt pha c vng ngn mch- ng c in mt pha m my bng in trng c in mt pha m my bng in dung

- ng c in mt pha kiu in dung:+ C in dung lm vic+ C in dung lm vic v m my

1.5.3.3. S d 3 p vo l 1 p:a. in p ngun bng in p pha ca ng c

- S hnh 1.11 a+ in p ngun bng in p pha ca ng c U = Uf

+ in dung lm vic ca t in FU

fILVC 4800

+ in p lm vic ca t: UcU Nu ng in pha nh mc cang c ba pha, n v l ampe.


18/95

- S hnh 1.11 b+ in p ngun bng in p pha ca ng c U =Uf

+ in dung lm vic ca t in FU

fILVC 1600

+ in p lm vic ca t in:

Cch u dy theo s hnh 1.11b c u im hn s hnh 1.11a:Mmen m my ln hn, li dng cng sut kh, in dung ca t nh hn,nhng in p trn t ln hn.b. Khi in p ngun in 1 pha bng in p dy ca ng c 3 pha.

C th u dy theo s sau:

Hnh 1.11-ng c in mt pha kiu in dung

- S hnh 1.11a + U = Ud + FUfI

LVC 2800 + UcU

- S hnh 1.11b +U = Ud + FUfI

LVC 2740 + UcU 15,1

1.6. dy qun ng c khng ng b.

1.6.1. dy qun ng c khng ng b ba pha.Q tr d tr t :

N

L1

U1

U2 W2

W1

V1

V2

C1

M

b)

N

L1

U1

U2 W2

W1

V1

V2

C1

M

b)

a)b)


19/95

. S tr dy q Stto , dy q lp (Xp p):

2. tri b dy qun tato kiuXp p :


20/95

1.6.2. dy qun ng c khng ng b mt pha.

18765432110987654321

13

YX C

A B

U1~

4


21/95

Bi 2 V s dy qun ng c

1. hi nim chungv dy qun.

1.1.N v.

Cm ng ra sc in ng cn thit cho my lm vic. ng thi tham giavo qu trnh bin i trong my.

1.2. y tt.- To ra khe h mt t trng phn b hnh sin (i vi dy qun phn

cm) v m bo c mt sc in ng v mt dng in tng ng vi cngsut in t ca my (i vi dy qun phn ng)

- Sc bn ca cc pha phi bng nhau v tr s v lch pha nhau 1 gcnht nh (ba pha gc lch gc 2/3, hai pha gc lch /2)

- Tr v khng cc pha phi bng nhau.- Bn v c, v nhit, v in.- Tit kim c kim li mu, nht l phn u ni ca dy qun. - Ch to, lp rp, sa cha v bo dng c d dng.

1.3. Ph lo dy qTheo chc nng:

+ dy qun lm vic+ dy qun m my

+ Dy qun cnTheo s rnh ca 1 pha di 1 cc q: nguyn v phn s.Theo s pha: 3 pha, 2 pha, 1 pha.Theo cch thc hin dy qun:

+ 1 lp: dy qun ng khun, dy qun ng tm, v dy qun zizac+ 2 lp: dy qun xp v dy qun sng..

2. Nhng c s v s dy qun

2.1. dy.Mi dytrn s tri (hnh 2.1) c to bi hai cnh nm trong hai

rnh cch nhau mt bc qun dy y; Phn ca bi dy nm trong cc rnh cgi l cc Cnh tc dng, phn cn li ca bi dy-ni lin hai cnh tc dngc gi l phn u ni. Dy qun mt lp th c hai cnh ca bi dy v phnu ni c biu din bng nt lin; Vi cun dy qun hai lp th cnh tcdng v phn u ni nm lp trn cng c biu din bng nt lin, cnh tcdng th hai ca bi dy s nm lp di ca rnh khc nn che khut Ta

biu din bng ng nt t. Phn u ni b cc bi dy khc che khut cngc biu din bng nt t.


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Hnh 2.1. Bi dy v t bi dy

2.2. t d.Cc phn dy c t trong cc rnh ca li thp v qut t trng ca

cc cc t khe h gi l cc cnh tc dng.

2.3. dy.

Ni tip cng tn: Ngha l

ni cc u cng tn ca hai bi dylin tip vi nhau. V d: u t bith nht vi u t bi th hai, cuit bi th nht vi cui t bi thhai.Vi cch u ni tip cng tn ta

c:

cc = bi dy

Hnh 2.2. u cng tn

Ni tip khc tn: Cc u khc tnca hai bi dy lin tip c nivi nhau. V d: u t bi th nhtvi cui t bi th hai hoc cui t

bi th nht vi u t bi th hai.Khi u ni tip khc tn:

cc = 2 x bi dy Hinh2.3. u khc tn

Qua hai v d trn ta thy rng:Cng vi hai bi dy nhng vi hai cch nicng tn v khc tn ta s c s cc khc nhau. Quy lut v mi quan h gias bi dy v s cc cc cch ni s c s dng rt nhiu trong qu trnhthc hnh v s tri, u ni cc b dy qun Statosau ny.Ngoi cch u ni tip, cc Bi dy, T bi dy cn c thc hin cch ni

song song; Trong trng hp ny, ty theo cch ni song song cc bi dy m tac quan h gia s cc v s bi dy khc nhau: Khi ni song song cc u cng tn: cc = 2 x bi dy


23/95

Hnh 2.4. u song song cng tn Ni song song cc u khc tn: cc = bi dy

Hinh 2.5. u song song khc tn

2.4. dy q.L k/c gia cnh t/d u v cui ca mt bi dy.y = (Khong)+ = 1 ( y = )

Qun bc + >1 ( y > ) Qun bc di+


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trng hp dy qun mt lp v hai lp, vi s bi dy trong mt t bi dy l q= 2.

T bi dy trong trng hp ny c to bi cc bi dy c kch thcging nhau Ta gi l T dy . Nu cc bi dy trong mtt bi dy c kch thc khc nhau, bi dy nh nm trong lng ca bi ln, ta

c T dy t. Tng ng ta c b dy qun kiu ng khun,ng tm.

Hnh 2.6. Kiu dy qun

Vic u ni tip cc t bi dy ca cc pha s quyt nh s cc cang c, vy l s quyt nh tc quay ca ng c. Cc bi dy s c uni tip nhau theo mt trong hai cch: Ni tip cng tn hoc ni tip khc tn.

2.6. .Bc cc l khong cch gia hai cc t lin tip. Nu s rnh li st l

Z, s i cc l p th bc cc c tnh theo s rnh l

= Z/2p

2.7. l p r l tp.

Gc lch pha gia hai rnh lin tip l: = p.2/Z

2.8. Dy q t lp, dy q lp.* L kiu qun trong mt rnh ch cha mt tc dng (mt cnh ca mt

bi dy gm nhiu si) trong ton b s rnh ca my in (kiu qun mt lp).c p dng qun c trong iu kin qun ng tm, ng khun v qun

sng. * L kiu qun trong mt rnh cha hai cnh tc dng (hai cnh ca haibi dy) ca hai bi dy thuc cng mt pha ton t q nu y = v c mt scnh cha hai cnh tc dng ca hai bi dy khc nhau nu y < hoc y > trong ton b s rnh ca my in (kiu qun hai lp).

c p dng c trong kiu qun ng tm, ng khun v sng kp nhng my in hoc ng c in yu cu Mmen khe v n nh.

2.9.S p dy t pB dy qun cang c in xoay chiu ba pha c chia thnh ba cun

dy t lch nhau 1200in- Mi b cun dy c gi l mt pha


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z= 2p

2 .

zq

p m

2tb

zy

p

0.360P

Z

0120

p

y

+ Mi pha gm mt hay nhiu t bi dy+ Mi t bi dy gm mt hay nhiu bi dy+ Mi bi dy gm gm mt hay nhiu vng dy.

3. Phng php v s dy qun (s tri) stato ng c khng ng bba pha;

3.1. Dy q t lp.

L kiu qun trong mt rnh ch cha mt tc dng (mt cnh ca mt bidy gm nhiu si) trong ton b s rnh ca my in (kiu qun mt lp).

c p dng qun c trong iu kin qun ng tm, ng khun v qunsng.

nh ton thnh lp s tri b dy my in xoay chiu 3 pha:+ Tnh ton cc thng s v cch v

- Bc cc:()

Trong : z l s rnh2p l s cc

- c tnh q: (c tnh dy qun)L s cnh tc dng c b tr di mt cc t ca mt pha dy qun.

Trong m l s pha

- Bc qun trung bnh

Nu y = (bc th = 0)Trong thc t nu qun y th ngi ta cho lc .yd= yd. - Bc pha: yp

L khong cch gia cc u pha hay ca cui pha to thnh gc lch 120 0in.

trong c gc in ca mt rnh chim.

- Tnh s bi dy ton my (n)Gi s t bi dy ca mt pha l u th u = p (trong p l s i cc). Th s

t bi dy ton my l n = u.m = 3.m = 3u = 3p- Cch v

Sau khi tnh ton cc thng s dng 3 mu biu th 3 pha hoc 3 n t khcnhau. Tin hnh ln lt v 3q mu khc nhau cho n ht s rnh Z. Sau nh ln lt cho n ht ri ni cc q ca cng mt pha theo bc qun ta c


26/95

2 369

2 2tb

yp

363

2. . 4.3

zq

p m

0 00.360 2.360

20

36

p

Z

0 0

0

120 1206

20p

y

2 369

2 2tby

p

s b dy. u v cui cc pha theo yp(Ch : nh du chiu dng in tcthi).

V d 1: Lp s tri b dy my in xoay chiu 3 pha theo kiu ngtm mt lp bc vi cc s liu:

Z = 36 rnh, 2p = 4, m =3, a = 1

Gii:* Tnh ton cc thng s:- Tnh v y = nn

- Tnh q:

Tnh

- Vy

- S t bi dy ton my: n=3u=3p=3.2=6* V s tri

S tri b dy my in xoay chiu 3 pha:Z=36, 2P=4, a=1, m=3

Kiu ng tm 1 lp bc tp trung

Hnh 2.6. S ng tm 1 lp bc V d 2 Lp s tri b dy my in xoay chiu 3 pha theo kiung khunmt lp bc vi cc s liu:

Z = 36 rnh, 2p = 4, m =3, a = 1Gii:* Tnh ton cc thng s:


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363

2. . 4.3

zq

p m

0 00.360 2.360

20

36

p

Z

0 0

0

120 1206

20p

y

2 369

2 2tb

yp

363

2. . 4.3

zq

p m

0 00.360 2.360 20

36

p

Z

0 0

0

120 1206

20p

y

Tnh v y = nn

Tnh q:

Tnh

Vy

S t bi dy ton my: n=3u=3p=3.2=6* V s tri


Hnh 2.7. Kiu ng khun 1 lp bc tp trung

V d 3 Lp s tri b dy my in xoay chiu 3 pha theo kiu ng khunmt lp bc t mc xch vi cc s liu:

Z = 36 rnh, 2p = 4, m =3, a = 1

Gii:

* Tnh ton cc thng s:

Tnh v y = nn

Tnh q:Tnh

Vy


28/95

369

2 4

Zy

p

363

2 4.3

Zq

pm

S t bi dy ton my: n=3u=3p=3.2=6

V s tri


Hnh 2.8. Kiu ng khun1 lp bc mc xch

3.2. Dy q lp.

* Dy q 2 lp xp+ Kiu qun hai cnh tc dng trong mt rnh c q l s nguynL kiu qun trong mt rnh cha hai cnh tc dng (hai cnh ca hai bi

dy) ca hai bi dy thuc cng mt pha ton t q nu y = v c mts cnhcha hai cnh tc dng ca hai bi dy khc nhau nu y < hoc y > trongton b s rnh ca my in (kiu qun hai lp).

c p dng c trong kiu qun ng tm, ng khun v sng kp nhng

my in hoc ng c in yu cu Mmen khe v n nh.Kiu qun hai cnh tc dng trong mt rnh q l s nguyn.* Tnh ton cc thng s:Phn tnh ton cc thng s c bn nh phn b dy mt lp ch khc l

s t bi dy s tng ln gp i v s bi dy ca b dy bng s rnh song svng dy trong mt bi t hn kiu mt lp.

* V d 1: Lp s tri b dy my in xoay chiu theo kiu ngkhun hai lp bc vi cc s liu:

Z = 36, 2p = 4, m = 3, a = 1

+ Tnh ton cc thng s:


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00360 2.360 20

36

p

Z

0120 1206

20p

y

369

2 4

Z

p

363

2 4.3

Zq

pm

00360 2.360

20

36

p

Z

0120 1206

20py

Tnh yp

NnS t bi trong ton b b dy qun S = n = 3u = 3p = 6S tri b dy my in xoay chiu 3 pha:

Z=36, 2P=4, a=1, m=3

Hnh 2.9. Kiu ng khun2lp bc * V d 2: Lp s tri b dy my in xoay chiu theo kiu ng khun hailp bc ngn vi cc s liu: Z = 36, 2p = 4, m = 3, a = 1, =0.90+ Tnh ton cc thng s:

V qun bc ngn nn y = .= 0,90x9 =8,18

Tnh yp

Nn

S t bi trong ton b b dy qun S = n = 3u = 3p = 6

4. Dy qun stato ng c khng ng b mt pha.

4.1. Dy q t lp.Vic tnh ton cc thng s lp s tri b dy mt pha c thc hin

theo cc bc sau :


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1 : nh ton cc thng s :

Bc cc : =P

Z

2

Bc qun : y =P

Z

2( cng c bc ngn , bc hoc bc di )

c tnh dy qun : qlv =mP

Zlv.2

( m = 1 v mt pha )

qk =P

Zkd

2

Bc pha : yp =

o90 ( trong =Z

P o360. )

( theo kinh nghim yp = qlv = 2 qk . rnh )

2. v s tri ( da vo cc thng s tnh ton v v nh b dy 3 pha )

i vi b dy qun stato ng c mt pha t in th cchv theo ccbc di y: lp dy q xp

c 1: K cc on thng song song cch u nhau ng vi s rnh Z v nh s t1 Z.

c 2: Cn c vo bc cc biu th qua s rnh phn ra cc cc t trnStato.

c 3:Trong vng micc t , cn c vo s rnh m cun dy chnh vcun dy ph s c, ta phn b s rnh ny xen k nhau, tc l, nu gi s bi

dy ca mt t bi dy cun dy chnh (LV) l qcv s bi dy ca mt t bicun dy ph l qp, ta thc hin ln lt theo quy tc: qc- qpqc- qp. Chon t cui cng.

c 4: Xc nh du cc t bng cch ghi chiu mi tn ln cc cnh tc dng,sao cho cc cc t lin tip phi tri du nhau.

c 5: Cn c vo s cc t bi dy trong mt cun dy v cch u cc uni ta k cc ng ni lin cc cnh tc dng hnh thnh cc t bi dyca cun dy chnh. u dy gia cc t bi dy cun dy chnh sao cho khi cdng in chy vo s khng lm thay i chiu mi tn m ta vch.

c 6: Cn c vo s rnh tngng c xc nh bi s lch nhau 90

0

(in) gia cun dy chnh v cun dy ph xc nh rnh khi u ca cun

dy ph, xc nh nh sau:

Zpd 360

90900

Vi l gc lch in gia hai rnh lin tip l:Z

pp hh360

.

Cch v cun dy ph ging nh cun dy chnh.

Ch :c bi dy ca cun dy chnh ycv bc bi dy ca cun dy phc th khng bng nhau, nn xc nh rnh khi u ca cun dy ph ta


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phi xc nh gc lch gia tm ca t bi dy u tin ca cun dy chnh vitm ca t bi dy u tin ca cun dy ph.

c 7: Kim tra li ton b cun dy chnh v cun dy ph vi cch u tngcun sao cho cc cc t lin tip phi tri du nhau.3 . hn xt v s , v dy qun

V dMt ng c in xoay chiu khng ng b mt pha rto lng sc dng dyqun m my c Z = 24, 2p = 4, Zlv = 2/3Z. Hy v s tri mt lp b dyqun.

a. rc tin ta tnh ton mt vi thng s:

a- Bc cc: 64

24

2

p

Z

b- S phn t di mt cc: 61.4

24

.2

mp

Zq

c-

Bc qun dy: )71(6

pc yy d- V ng c dng dy qun m my nn di mi cc t cun dychnh chim 2/3 s rnh (4 rnh), cun dy ph chim 1/3 s rnh (2rnh).

Gc lc pha: 64

24

2

p

Z

b. hc hin v s :V s kiu ng khun n gin (kiu hoa sen hay dc lng tm):

c 1:K 24 on thng song song cch u nhau v nh s t 1 24 (hnh

2.10).c 2:Chia 24 rnh lm bn bc cc , ni bc chim 6 rnh (hnh 2.10).c 3:Trong vng mi cc t , cun dy chnh chim 4 rnh, tip theo cundy ph chim 2 rnh: ta thc hin ln lt theo quy tc: q c- qpqc- qpqc-qpqc- qpqc- qp(hnh 2.10).

1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

qA

qB qA qB qA

qB qA qB

1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

A X

p

Z

2


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Hnh 2.10.Trnh t thc hin v s theo dng ng khun

1 2 3 4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

A XB Y

A B

Hnh 2.11 S dy qun dng ng khun ca ng c in xoay chiukhng ng b mt pha vi cc thng s Z = 24, 2p = 4, qA= 4, qB= 2, yA= 7,yB= 7.

c 4: Xc nh du cc t: ghi chiu mi tn ln sao cho cc cc t lintip tri du xen k nhau (hnh 2.11).

c 5: Trong ton b 24 rnh, cun chnh chim 2 t bi l 2x4x2 = 16rnh, cun dy ph chim 2x2x2 = 8 rnh. Ta k cc ng ni lin vi cccnh tc dng hnh thnh cc t bi dy cun dy chnh: t bi u tinchim cc rnh: 1 7, 28, 39, 49 vi yc= 6. T bi dy th hai chim ccrnh: 1319, 1420, 1521, 1622 vi yc= 6. u dy gia hai t bi saocho khng lm thay i chiu mi tn vch (hnh 2.11).

c 6: Cn c vo Z/4p = 3 rnh, ta xc nh rnh khi u cun dy phsao cho gia tm ca t bi dy u tin cun dy chnh cch tm ca t bi dyu tin cun dy ph l 3 rnh hoc rnh u tin ca cun dy ph cch rnhu tin ca cun dy chnh 1/2= 3 rnh (1 ) (hnh 2.11).

V s dng ng khun phn tn i vi nhng s dy qun khi t bi dy c s bi dy nhiu (2, 4, 6,

8bi), kch thc phn u ni ca cc bi dy s kh di. gim bt kchthc phn u ni ca cc t bi dy nh trn ngi ta thc hin phn tn t

bi dy ra lm hai phn bng nhau. Cch v: Ta cng thc hin cc bc tngt nh trn, y mi t bi dy cun dy chnh c hai bi dy (hnh 2.11).V d

Lp s tri b dy ng c mt pha chy t c cc s liu sau : z = 24;

Zlv =3

2 Z nn Zlv =3

2 .24 = 16 rnh , v Zk = 24 16 = 8 rnh

Gii

Bc 1. Tnh ton : Tnh bc cc : =P

z

2=

4

24 =6

Tnh bc qun y : ylv = lv.= 0,67.6 = 4,02 = 4 ( khong )yk = k.= 0,83.6 = 4,98 = 5 ( khong )


33/95

c tnh dy qun :

qlv =P

Zlv

2=

4

16 = 4

qk =P

Zkd

2=

4

8 = 2

Bc pha yp : =

Z

P360. =24

360.2 = 30o

yp =

o90 =o

o

30

90 = 3 ( khong )

Ta thy rng, cun dy qunng khun n ginc bc bi dy l bc (yc= yp= = 6), trong khi cun dy qun ng khun phn tn c bc

bi dy b hn (yc= yp= 5). Chnh v vy, nn dng ng khun phn tn cs dng ph bin.

4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

XB Y

B

1 2 3

A

A

2

5

20

23

Hnh 2.12.S dy qun dng ng khunphn tn ca ng c inxoaychiu

khng ng b mt pha vi cc thng s Z = 24,2p = 4, qA= 4, qB= 2, yA= 4,yB= 5.

V d t:Cch v cng tng t, nhng t bi dy y l nhng t bi dy kiu ng

tm (m con) (hnh 2.4).


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4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

XB Y

B

1 2 3

A

A

Hnh 2.13. S dy qun dng ng tm ca ng c in xoay chiu

khng ng bmt pha vi cc thng s Z = 24, 2p = 4, qA= 4, qB= 2.V d

Thnh lp s tri b dy my in mt pha , c Z = 18 , 2P = 2, Zlv

=3

2 Z , lv = 0,66, k = 0,88. Qun ng tm mt lp ( bc ngn )

Gii* Tnh ton cc thng s :

v Zlv =3

2 Z nn Zlv =3

2 .18 = 12 rnh v Zk = 6 rnh

=P

Z

2=

2

18 = 9

ylv = lv.9 = 0,66.9 = 5,94 = 6 khong yk = k.9 = 0,88.9 = 7,92 = 8 khong

qlv =P

Zlv

2=

2

12 = 6

qk =P

Zkd

2

=2

6 = 3

=Z

P o360. =18

360.1 = 20o

yp =20

90 = 4,5 ly yp = 4

* V s tri da theo cc s liu tnh ton :


35/95

b dy ny cun dy khi ng ri u trn hai na chu vi li thpStator , mt cun dy khi ng s chia i s vng v phn u v 2 pha,chnh v vy ti rnh 5 v rnh 14 ta thy c 2 lp ( nhng cng mt pha dykhi ng ).

4.2.Dy q lp.* lp dy q lpT bc 1 n bc 6 lm tng t nh lp s dy qun mt lp, ci khc

y l cch t cc cun dy v cch chn h s dy qun (h s bc ngn).Cch chn h s bc ngn nh bng di:

S rnh di mt cc camt pha

1 2 3 4 5 6 7

Bc cc t 3 6 9 12 15 18 21Bc qun dy y 2 5+1 7+1 10 12 15+1 17+1T s bc ngn (= y/) 2/3 5/6 7/9 10/12 12/15 15/18 17/21

rnh t cch lp s b dy qun hai lp nh sau:Cun dy chnh:T th nht:Bi th 1: {1 (y + 1)}Bi th 2: {2 (y + 1 + 1) = (y + 2)}


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Bi th 3: {3 (y + 1 + 1 + 1) = (y + 3)}..Bi th n: {n (y+ n)}T th 2:Bi th 1: {(1 + ) (1 + + y)}

Bi th 2: {(1 + ) + 1 {(1 + + y) + 1}}Bi th 3: {(1 + ) + 1 + 1 = ((1 + ) + 2) {(1 + + y) + 2}}..Bi th n: {(1 + ) + (n1) {(1 + + y) + (n1)}}T th 3:Bi th 1: {(1 + + ) = (1 + 2) (1 + 2 + y)}Bi th 2: {(1 + 2) + 1 {(1 + 2 + y) +1}}Bi th 3: {(1 + 2) + 2 {(1 + 2 + y) +2}}..

Bi th n: {(1 + 2) + (n1) {(1 + 2 + y) + (n - 1)}}T th n, bi th n: {1 + (n 1)+ (n1) {1 + (n1) + y + (n - 1)}}Cun dy ph:u cun ph tnh theo rnh gia tm ca t bi dy u tin cun dy chnh

vi tm ca t bi dy u tin cun dy ph (Z/4p). Cch t cc bi dy cngtng t cun dy chnh.

Ch , y ch s c du phy trn biu th cnh ca bi dy nm lp di rnh, cn ch s khng c du phy trn biu th cnh ca bi dy

nm lp trn ca rnh.V d:V s b dy qun hai lp ca ng c in xoay chiu khng

ng b mt pha, dng t in m my, c Z = 24, 2p = 2, bi dy bc ngnvi h s bc ngn = 9/12.

Gii:i. Tnh ton cc thng s:

a. Bc cc: 122

24

2

p

Z

y l loi ng c dng dy qun m my, nn cun chnh chim s rnh:

1624.32

32 ZZc (rnh), cn cun dy ph chim l:

824.3

1

3

1 ZZp (rnh).

b. S rnh di mt cc m cun dy chnh chim

l: 81.2

16

.2

mp

Zq cc (rnh)

c. S rnh di mt cc m cun dy ph chim l: 41.2

8

.2

mp

Zq

p

p (rnh)

d.

Bc qun dy: 912.129. pc yy (rnh)


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e. Gc lch tnh theo rnh gia tm ca t bi dy u tin cun dy chnh

vi tm ca t bi dy u tin cun dy ph l: 61.4

24

4

1 p

Z (rnh)

ii. V s :Thc hin cc bc 1, 2, 3, 4, 5 v 6 tng t nh cc bc v s dy

qun mt lp, nhng y, ch l mi rnh c hai cnh tc dng.

Ch , bc 4 ta nh du chiu mi tn i vi nhng cnh bi dy nm lp trn, cn nhng cnh bi dy nm lp di sau khi v xong cc bidy, v vi nhng b dy qun hai lp bc ngn th c th s c mt s rnh chai cnh bi dy lp trn v lp di khng cng chiu dng in.S t bi dy ca cun dy chnh v cun dy ph l n = 2p = 2 t. S bi dy ca cun dy chnh trong mt t l 8 bi (bng qc).S bi dy ca cun dy ph trong mt t l 4 bi (bng qp).

Ta lp c bng nh sau:Cun dy chnh:T th nht:Bi th 1: (1 y + 1 = 10')Bi th 2: (2 y + 2 = 11')Bi th 3: (3 12')Bi th 4: (4 13')Bi th 5: (5 14')

Bi th 6: (6 15')

Bi th 7: (7 16')Bi th 8: (8 17')T th hai:Bi th 1: (1 + = 13 1 + + y = 22')Bi th 2: (1 + + 1 = 14 1 + + y + 1 = 23')Bi th 3: (1 + + 2 = 15 1 + + y + 2 = 24')Bi th 4: (16 1')Bi th 5: (17 2')Bi th 6: (18 3')

Bi th 7: (19 4')Bi th 8: (20 5')Cun dy ph:Cn c vo gc lc xc nh rnh khi u ca cun dy ph. Ta nhn

thy, tm ca t bi dy th nht ca cun dy chnh nm rnh s 9 v theocch t cc bi dy th tm ca t bi dy th nht ca cun dy ph s l rnhth 15 (6 rnh). Tc l, rnh khi u ca cun dy ph s l rnh s 9 (hnh2.14)


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4 5 6 7 8 9 10 1 2 3 4 5 6 8 9 20 1 2 3 47

XB Y

1 2 3

A

17

21

Hnh 2.14. S dy qun hai lp ca ng c in xoay chiu khng ng

b mt pha dng t in m my vi cc thng s Z = 24, 2p = 2, = 9/12.Bi tp1) Ly mu b dy qun stato ng c mt pha vng chp v ng c mt phat in.2) V s u dy ng c in ng c mt pha vng chp 2 cc, 2 t bin.3) V s u dy ng c in ng c mt pha vng chp 4 cc, 2 t bin thnh ng c 2 cc.4) V s u dy ng c in ng c mt pha vng chp 4 cc, 4 t bi

n, c mt bi dy s.5) V s u dy ng c in ng c mt pha vng chp 4 cc, 4 t bin, c 4 bi dy s.6) V s u dy ng c in ng c mt pha vng chp 6 cc, 6 t bin,s dng 2 cp in p khc nhau.7) V s u dy ng c in ng c mt pha vng chp 16 cc, 8 t bin.8) V s u dy ng c in ng c mt pha vng chp 20 cc, 20 t bin.

9)

V s b dy qun mt lp ng c mt pha t in c Z = 16, 2p = 4.10) V s b dy qun mt lp ng c mt pha t in c Z = 16, 2p = 4, 3s (2 cun s) lng chung rnh vi cun khi ng.11) V s b dy qun mt lp ng c mt pha t in c Z = 16, 2p = 4, 3s (1 cun s s dng tng cp dy s i xng),cun lng chung rnh vicun khi ng.12) V s b dy qun mt lp ng c mt pha t in c Z = 16, 2p = 4, 3s (2 cun s) lng chung rnh vi c hai cun dy.13) V s b dy qun mt lp ng c mt pha t in c Z = 24, 2p = 4. 14) V s b dy qun mt lp ng c mt pha t in c Z = 24, 2p = 6. 15)

V s b dy qun mt lp ng c mt pha t in c Z = 36, 2p = 6.

16) V s b dy qun mt lp ng c mt pha t in c Z = 48, 2p = 12.


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17) V s b dy qun mt lp ng c mt pha t in cZ = 48, 2p = 16.18) V s b dy qun mt lp ng c mt pha t in c Z = 36, 2p = 18.19) V s b dy qun mt lp ng c mt pha t in c Z = 28, 2p = 14.20) V s b dy qun mt lp ng c mt pha t in c Z = 18, 2p = 18.21) V s u dy trong ng c mt pha t in c Z = 24, 2p = 2, nm t

bi nm kiu m con.22) V s u dy trong ng c mt pha t in c Z = 36, 2p = 4, micun gm hai t bi bn v hai t bi nm ng khun.


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Bi 3 Tho lp ng c in.

1. Trnh t tho ng c

Hnh3.1.

Trnh

tth

o

ng

c

in

xoay

chiu

Trnh t tho ng c gm cc bc nh sau: 1:Tho ng c ra khi my sn xut v cc b phn truyn ng


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Ch : S dng Cl, mlt hoc tucnvtng chng loi ph hp vinhng bulng, cu, vt trnh b nt, v, v trn u, chy xn hoc gy vch cc tm m.

2:V sinh pha ngoi ng cDng bn tri hoc my nn kh lm sch bi bn du m bm trn

thn ng c in v cc b phn khc. 3:Tm hiu cu to thc t, cc thng s ca ng c. Ghi chp tnh trngmy trc khi tho :+ Quay trn , kt , st ct ...?+ S nguyn vn ca cc chi tit.+ Tnh trng k thut in.+ S pht nhit, nhng h hng.+ Xc nh bin php tho c th.+ Chun b dng c tho ph hp, vt liu phc v tho, lp, bo dng.

+ T chc ni lm vic thong rng, nh sng.+ nh du v tr lp rp cn thit sau ny lp li khng b sai ln ( v tr ccu dy, v tr mt bch, cnh qut, su Puli, bnh ai . v ..v.)+ o cc thng so in tr thun ca b dy. Ghi kt qu.o in tr cch in gia cc pha. Ghi kt quo in tr cch in gia cc pha vi v. Ghi kt quCh : Nu in tr cch in nh hn 0.5 Mth phi sy ng c.

Hnh 3.2. o in tr cch in gia pha vi v - o in tr cch in gia cc

pha 4:Tho buli ra khi trc ng c.S dng vam 2 cng, 3 cng hoc dng bn p thy lc p cho puli ra

khi trc ng c.


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5:Tho np che cnh qut gi ngoi (b phn che cnh qut), cnh qutra khi trc ng c. Sau tho cnh qut, nu l then gi gia cnh qut vtrc ng c th s dng vam tho hoc s dng hai bulng ph hp sit voren to sn y cnh qut ra, trng hp chbt vt ta s dng tucnvit tho.

6:Tho np m (b phn che bi ngoi vi loi vng bi cu) ca mttrc ng c.Ch : nh du v tr bulng np m trc, sau, trong, ngoi trnh trng hp

sai lch v tr ca np m trc, sau, trong v ngoi.

7:Tho bulng ca np trc, np sau ca ng c.Dng tucnvt hoc cl, mlt ph hp vi vt hoc bulng, cu tho nptrc, np sau. Khi tho phi ni u, i xng cc bulng, cu. Sau dng

ba cao su hoc ming g, tng (ng, nhm) vi ba ngui hoc dng bangui vi c mng c vo khe h lp ghp gia np v thn, lm np sauca ng c bung ra khi thn v trc ng c. nh ba va phi, u u, tt v cy dn bn gc ti cc v tr i xng v vo cc g ca np, th n.Trnh lm lch mo, nt, v np.

Ch : nh du v tr np trc, np sau trnh trng hp sau khi lplm sai lch, nhm ln v tr ca hai np my.

8:Rt Rto v np sau ra khi Stato.Lt giy cch in hoc ba ln phn u ca b by. Dng Palng, cutrca Rto v np sau ra khi Stato. Trnh lm xy st (hng cch in) bdy qun.


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Ch : u my in c chi than th trc tin ta phi nhc chi than ra khihp chi than, vi my in mt chiuth phi nh du ng trung tnh hnhhc ca chi than trn vnh gi chi than v np c nh gi chi than khilp khi b nhm ln. Sau khi rt Rto v np sau ra khi Stato ta phi k ln

gi khng Rto v trc trc tip xung nn xng hoc mt bn.

2. Lm sch ng cCc chi tit my phi cra sch bng xng hoc du ha v lau kh, sy

kh sau khi ra. B phn dy qun nn dng hi kh nn thi bi bn, trng

hp b dnh du m nhiu phi ra th dng xng khng pha ch hoc du nh ra sau sy kh ngay.

3. im tra tng qut tnh trng ng c;

3.1.Xe xt v yV my thng c cc b phn lp ghp d h hng nh v l bt Bu lng,chn ren, cong vnh cnh qut, quay st c kh, bin dng ai khp ni... Nhnchung cc chi tit d nh ca thn my c h hng hoc bin dng u phic sa cha hoc thay th kp thi, trng hp phi hn p, ch cng ngh

hn thch hp, khng gy cong vnh hoc bin dng do nhit

3.2. tr rto- Quan st b mt li thp rto, nu thy b st, khng nhn th phi sa.- Trc v thn rto khng c lp lng, trc phi thng, v tr lp rp phinhn.- Vi rto dy qun cn ch : u dy qun c b xc sat khng, nu bi

bn do du m phi ra sch bng xng khng pha ch v sy kh, kim tra schc chn ca ai hm u dy qun.

-

i vi rto kiu lng sc, kim tra cc thanh dn trong rnh b lng, t,nt khng. B mt li thp phi sch nhn.


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- Cnh qut trn thn trc phi chc chn, khng b bin dng hoc gy v,tonb phi c ra sch bi bn hoc du m.- Kim tra vnh trt, vnh gp: B mt vnh trt phi nhn sch, khng bvt lm, vnh gp phi trn u, khng b xm chy do nhit, cc l gp phicch in vi nhau v cch in vi v. Quan st cc l gp phi sch, khng c

bi than, khng c vt dn in bc cu, dng dao ca chuyn dng, ca rnh vdng giy rp nh sch u. C gp vnh trt phi c c nh cht ch trntrc, khng c hin tng nt v phn thn cch in.

3.3. tr v ( )Kim tra vng bi, bc: vng bi sau khi ra sch phi quay trn, khng bi

d, khng c vin bi v, nu phi thay bi th dng vam tho ra khi trc v chnvng bi mi ng chng loi v p vo trc. Vic tra m vo bi phi ch iu kin lm vic v tc quay ca my chn loi m ph hp, c cc loisau khi s dng cn bit c:

+ M tc cao: c mu nu sm hoc en, m gc Natri, b mt mnhm, chu c nhit cao nhng s nc, d b phn ha. Dng thch hpcjcho cc bi vn hnh vi tc cao, mang ti ln, khng b ngm nc (dngcho ng c c tc t 1500 vng/pht tr ln).

+ M tc thp: l loi m gc Canxi, mu vng khng s nc,dng cho cc bi chu ti nh, tc thp (dng cho my c tc t 1500vng/pht tr xung).

+ M hn hp: Cn gi l m gc hn hp Natri v Canxi, do hai loim nu trn pha ch vi nhau hp thnh, n c mu vng hoc nu sm ty theo

t l pha trn, loi m ny dng thch hp cho my vn hnh cao tc, chu tiln, c th chng thm nc mc nht nh.

Vi my chy bc, khi kim tra bc cn ch : Bc v trc quay trn, hunh khng c d, b mt tip xc bc v trc nhn v c du bi trn, khithay bc mi phi r bc bng bt r v du, khi p bc v gi ch khng b lch gy bin dng

3.4. tr ttoTrn stato c li thp t, dy qun, v v thn my.

Cng vic kim tra sa cha c tin hnh bng cch:- Quan st mt trong stato nu thy c vt xc hoc l thp b x, bin dngphi sa, c thdng nm g v ba g nn, ni cn da th dng da sa nhngphi c tm ba cch in k m trnh xy xc st men dy v cng lkhng cho mt thp lt vo dy qun.-Nu li thp b r c th dng giy rp nh sch sau khi qut ln b mt lpsn cch in long v sy kh.- Kim tra cc u b dy c b xc st hoc vt l xm nhp v khng, khi

u b dy c biu hin lo ha, cch in gin mn th nn sy kh v qut ln

mt lp sn cch in (sn ph) ri tip tc sy kh sn.- Li thp stato phi c ghp cht ch vi v my.- V my, cc v tr lp rp phi nhn.


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4. Lp ng cTrnh t lp ngc li vi khi tho (chi tit tho sau th lp trc).

1:Lp Rto v np vo Stato. 2:Lp bulng ca np trc, np sau ca ng c. 3:Lp np m

4:Cnh qut vo trc ng c, Lp np che cnh qut gi ngoi (b phnche cnh qut),

5:Lp buli vo trc ng cMt s ch sau khi lp:-Kim tra s quay trn-Xc nh chiu quay ng-Kim tra li y v an ton cc chi tit-Vn hnh th kim tra tnh trng lm vic sau khi lp-Loi tr, sa cha ngay h hng khi vn hnh th pht hin thy

5. im tra hon tt.+Kim tra li cc c xem sitcht cha+ o cc thng so in tr thun ca b dy.o in tr cch in gia cc pha.o in tr cch in gia cc pha vi v.


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Bi 4 u dy vn hnh ng c in.

1. ngha cc s liu ghi trn bin my.- Trn v ng c gn nhn ghi k hiu v loi ng c, kch thc lp

t, s i cc, cc s liu nh mc, mc bo n, s xut xng, nmsn xut, khi lng,...

1) iu 3PN1604- - K t 3PN: ng c khng ng b 3 pha ro to lng sc phng n- - S 160: Ch chiu cao t chn ng cn tm trc quay (mm)- - K hiu bng ch S, M, L ch kch thc lp t theo chiu di thn- + S: Chiu di thn, kch thc lp t thn ngn- + M: Chiu di thn, kch thc lp t thn trung bnh- + L: Chiu di thn, kch thc lp t thn di- - i vi ng c c chiu cao tm trc quay di 90mm. K hiu

bng cc ch ci A, B, C ( V d: 80A, 80 B) kch thc lp t ngc ging nhau

-

S cui cng ch s i cc ng c- + S 2: ng c c s i cc 2p = 2 tng ng vi tc 3000

vng/pht- + S 4: ng c c s i cc 2p = 4 tng ng vi tc 1500



vng/pht

2) 3 phang c s dng li in xoay chiu 3 pha- 3) Cp F


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- Cp chu nhit ca vt liu cch in v cun dy ln nht l 1550C- 4) IP44- - IP l cp bo v ng c vi bn ngoi- - IP23 ng c kiu h ( nc v bi vo c bn trong cun dy)- - IP44 ng c kiu kn ( bo v c git nc ri vo bt k

hng no, bo v c vt l kch thc 1mm khng thm nhp vong c)- 5) 10HPcng sut trn trc ng c 10 m lc- 7,5kWcng sut ng c theo n v W- 6) /Y: 220/380V- 19,8/11,4A- - Li in 3 pha in p 220V ni tam gic , dng in dy nh

mc ca ng c 19,8A- - Li in 3 pha in p 380V ni tam gic Y, dng in dy nh

mc ca ng c 11,4- 7) 1445vg/ph- Tc quay trn trc ng c 1445 vng/pht- 8) 50Hz- ng c s dng li in c tn s 50Hz- 9) cos0,86- H s cng sut ca ng c in l 0,86- 10) h% 85,5- Hiu sut ca ng c tnh theo phn trm cng sut u vo 85,5%- 11) ExdIT3-

K hiu cp bo v n- - Ex biu th ng c in bo v n s dng trong m, hm l- - d ng c c kt cu v khng xuynn- - I ng c thuc nhm s dng trong cc m hm l mi trng kh

m c cha metan l kh gy chy n- - T3 nhit t bc chy ca bu khng kh ni thit b lm vic l

2000C- 12) 200- S xut xng l 200

-

13) 100kg- Khi lng ng c l 100kg


48/95

A

Z

C

VY

B

Uth

X

B

Y

XA

Uth

C

V

Z

Hnh4.1.Phng php dng ngun xoay chiu

2. Cch b tr cc mi dy ra trn hp ni.

2.1. Qy .

. t p pp

hng php dng ngun xoay chiu

Khi ni dy ng c 3 pha theo hnh 4.1a, ta c th coi nh l mt my binp cmng c cun s cp c to bi hai cun dy pha ni tip cng chiu,khi cho dng in xoay chiu chy qua cun dy s cp th trn cun AX v BYs sinh ra t thng a v bc chiu c xc nh theo qui tc vn nt chai.Hai t thng ny cng chiu, mc vng qua cun dy CZ ng vai tr l cunth cp nn t thng tng qua CZ l ln nht. Theo nh lut cm ng in ttrong cun dy CZ sinh ra mt sc in ng cm ng (E c 1,7Uth).Khi ,cc u dy Av B cng cc tnh, X v Y cng cc tnh. Vic xc nh u dycn li lm tng t.Khi ni dy ng c 3 pha theo hnh 4.1b, do hai cun dy u ngc chiunhau nn khi cho dng in xoay chiu chy qua cun dy s cp th trn cunAX v BY s sinh ra t thng a v bc chiu ngc nhau c xc nh theoqui tc vn nt chai.Hai t thng ny ngc chiu, mc vng qua cun dy CZ ng vai tr l cun

th cp nn t thng tng qua CZ b trit tiu. Trong cun dy CZ khng c scin ng cm ng (Ec 0). Khi , cc u dy Av B ngccc tnh, X v Yngc cc tnh. Vic xc nh u dy cn li lm tng t.

hng php dng ngun mt chiu


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Hnh 4.2. Phng php dng ngun 1 chiu.

Khi ni dy nh hnh 4.2 ta thy: Khi ng kho K, t thng ado cun dypha A sinh ra c xc nh theo qui tc vn nt chai. Nu K chuyn trng thit ng sang m th t thng aqua cun BY suy gim, theo nh lut cm ngin t trong cun BY sinh ra mt sc in ng cm ng E ccng chiu vichiu t thng a chng li s suy gim ca t thng.*) Kt lun: Nu K chuyn trng thi t ng sang m m in p cm ng cgi tr dng (Kim ng h Vnmet quay theo chiu dng ca thang chia) thu ni vi cc (+) ca Vnmet c cng cc tnh vi u ni vi cc (+) ca

ngun th, uni vi cc (-) ca Vnmet c cng cc tnh vi u ni vi cc(-) ca ngun th.Ch :+ Do sc in ng cm ng rt nh nn ng h th s dng loi milivn c vtr 0 nm gia.

+ Khi s dng ng h vn nng, cn ch n ngun pin trong ca ng h.T tr x t Khi b dy my in mt pha hay 3 pha khng phn bit c cc u dy ni dng vo hp cc ni dy th phi tin hnh xc nh cc tnh tc l xcnh u u v u cui ( theo gi thit ) cacc pha dy qun .c hai cch xc nh thng dng nh sau :+ Cch th nht: Dng ngun mt chiu ,

Ngun mt chiu c th l Pin hoc cqui ( cc ngun ny rt d c vkch thc gn nh ); cch lm nh sau :

Chn mt ng h mV mt chiu ( hoc in k c nhy cao ), ng hny c v tr O gia bng khc cng tt ; chn ngun pin hoc c qui cU = 3v 9v.Trc ht dng ng h o vn nng ( thang o ) xc nh cc u dy cacng mt pha ( nu cn thit treo bin ghi nh vo cc u dy tm c ):Hnh 4.3


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3 3'2 2'1'1

Hnh 4.3: Treo bin gi thit ghi nh

Cc u dy 1 1, 2 2, 3 3 l ca cng mt pha; sau ni mch theonguyn l sau : (Hnh 4.4)

Nguyn l mch kim tra cc tnh dng ngun 1 chiu

Cch thc hin: ng cng tc K ng thi quan st mV mt ( ng K v mngay ) : c hai trng hp c th xy ra :

* ng k kim mVmt ch lch chiu kim ng h ( tc l lch sangphi ca v tr O ) th kt lun : u ni vi + ng h v u ni vi + ngunl khc tn ( Nu coi u 1 l u u ca pha s 1 th u 3 s l u cui ca

pha s 3 ) treo bin ngay li pha s 3 ghi nh .* ng K kim mVmt ch lch ngc chiu kim ng h ( tc l ch

v pha tri ca v tr O ), th kt lun : u ni vi + ng h ( 3) v u nivi + ngun (1) l cng tn ( cng l u u ca pha 1 v pha 3 )gi nguyn ngun pha 1 1, ni mV mt vo pha 22v thc hin ngcng tc K nh trn, s xc nh c tn ca pha 2 2.gi thit tm c cc u 1,2,3 l cc u u ca 3 pha - t tn tng ng lA, B, C th cc u 1, 2, 3 tng ng s l X, Y, Z ( cc u cui ca 3 pha )+. Cch th hai Dng ngun xoay chiu

Chn ngun th l xoay chiu khong 30v n 60v thng qua my bin p; chn V mt xoay chiu c thang o 0 100V;

Dng ng h vn nng ( thang o ) xc nh c cc u dy trongcng mt pha v t tn ghi nh cho cc u dy ( ging nh cch lm phng php th nht );


51/95

Sau , mc mch o nh hnh v di y :

Nguyn l mch kim tra cc tnh dng ngun xoay chiu

Chnh Uth V1 ch khong 30V n 60V , ni mch th theo s trn . ngp t mt AB v quan st ng h V2, s c hai trng hp xy ra :- V2 ch 0Vth kt lun 2 u ni chung ( 2 3 ) l cng tn ( cng l uu hoc u cui ca hai pha 2 v 3 )- V2 ch > 0v ( 1,5 1,7 )Uth - th kt lun 2 u ni chung ( 2 3 ) lkhc tn ( gi thit 2 l u u pha 2 th 3 l u cui pha 3 )i ngun th sang pha 2 2 hoc 33 v ni V2 vi 2 pha cn li trong c pha 11 cha bit tn , thc hin php o nh trn s bit c tn ca pha

1- 1 v nh vy c 3 pha s c bit tn qua 2 ln o .Khi bit tn cc u dy, s u vo hp cc nh sau ( cn u ng

tn nh ghi trn hp cc )Ch :xc nh u u v u cui ca cun dy lm vic v cun dy khi

ng ca my in mt pha dng phng php ngun mt chiu ging nh cp .

2.2. Qy tr dy r tr p .Khi bit tn cc u dy, s u vo hp cc nh sau ( cn u ng

tn nh ghi trn hp cc )


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53/95

b in cha c nghim minh. in p thc t c th thp hn 5% so vi nhmc.rc khi cho vn hnh, phi kim tra ng c in theo ni dung sau y:Lm v sinh cng nghip ni t my, lau sch bi, bn v du m bm vo

ng c, kim tra trong v ngoi loi tr vt l ri vo.

Kim tra mc du ni du trn v di ( i vi cc ng c khng ng bcao th ) v khi cn th b sung dn cho lng yu cu.Dng tay hoc tay n quay ng c theo chiu quay ca ng c ( c mi tn

ch chiu quay ca ng c ) xem c nh khng.Kim tra bu lng b my, bu lng hp u dy, khp ni v dy tip t an ton

i vi ng c.Kim tra chi than v kh nng p chi than trn vng trt, lau sch vnh tip

xc ( i vi ng c dy cun v ng c ng b ).Nhng cng vic phi lm trc khi ng in vo ng c my bm.

Kim tra in tr cch in ca ng c trc khi ng in vo ng c mybm.Dng tay quay th trc ng c my bm xem c trn, nh khng.Kim tra bt cht ca cc bu lng, v tnh trng dy tip t , kim tra du

m cho vo bi.Kim tracc thit b khi ng v bo v ng c .Kim tra in p th cp my bin p lc ( in p, dy v pha ), kim tra s

ng u pha.i vi ng c khng ng b r to dy qun cn thm:

Khe h gia chi than v khung gi chi than phi trong phm vi 0,1-0,2mm. khung chi than cch vng trt ( vng nhn in ) nn t 2 3 mm; plc chi than phi m bo cht khng sinh ra tia la( vo khong 0,1 0,15kg/cm2 ).

3.2. V

Khi ng, ng in vo ng cTu theo trang b k thut, chng loi, v v tr lp t ... mi ng c s c

quy trnh vn hnh ring cho mnh.Tuy nhin nguyn tc c bn l :

Thc hin nguyn tc ng ngun n ph ti.Khi ng ln lt tng ng c m bo s my lm vic phn b u n

nh cng trnh.Mi ln khi ng khng kt qu, phi tm nguyn nhn v sau khi s l xong

mi c khi ng li trng thi ngui, s ln khi ng khng qua 2 n 3 ln. trng thi nng nu khi ng khng kt qu phi tm nguyn nhn, s l vsau thi gian php mi c khi ng li.im st ng c ang vn hnh

Khi ng c ang trng thi lm vic, ngi vn hnh phi lun theo di:Dng in ph ti ca ng c : Am pe k ch dng in ph ti ca ng c

(dng vo Stato) phi nh hn hoc bng dng in nh mc (ghi trn nhn)


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ca ng c. Khi dng in ph ti khng n nh cn theo di cht v tmnguyn nhn.

Nhit ng c : Nhit pht nng ca ng c khng c pht nng qutr s nhit cho php. Nhit pht nng ca ng c ph thuc vo cu to,loi in p, cp cch in ... do nh ch to quy nh.

Thng thng, ng c h th, cch in cp A hoc B nhit pht nngkhng qu 800C khi o bng nhit k thu ngn cm vo l bu lng trn thnmy. pht nng cc gi trc, i vi cc ng c h th, chy bng ln nhit ti a khng vt qu 700C, v khng vt qu 500C ti cc ni du lm mtca ng c cao th.in p t vo ng c : Tr s in p t vo ng c ( thng qua vn k )khng c sai khc (trn hoc di) 5% so vi in p nh mc ca ng cTing ku ca ng c phi u, khng c ting gm khc thng v ting c

st c kh.i vi ng c cao th, mc du trong cc gi ch thp phi nm ng vchquy nh, mu sc du bnhthng, khng r r du, du, m khng vng v bidy Stato.ng c khng rung mnh : khi vn hnh, rung ca ng khng vt qu trs cho php (c th tham kho bng sau).

Tc ( vg/pht ) 1500 1000 750 v thp hnBin rung ca

gi trc (mm)0,1 0,13 0,16

4. im tra dng in khng ti.Cp ngun cho ng c lm vic ch khng c ti, dng ampemet

hoc ampe km ln lt o kim tra dng in cc pha. Nu gi tr dng in cc pha l bng nhau th chng t ng c lm vic tt, cn nu nh c s khcnhau gia cc gi tr dng in o c cc pha th ng c lm vic s cting ku rt.


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Bi 5: a cha ng c khng ng b mt pha

1. Qun dy ng c mt pha (My bm nc, my mi)

1.1. Tho v v sinh ng c.- ng c mt pha thng c cng sut nh, ch yu s dng trong dn dng.Vic tho lp bo dng phn c kh nhn chung rt n gin v ph thuc votng loi my, v nguyn tc cn thc hin theo trnh t chung sau y:Chun b dng c, thit b tho lp v nilm vic.- Tm hiu tnh trng my trc khi tho.- nh du cc v tr lp rp phc tp khi lp rp khng b sai ln (k c nhdu cc u dy dn in).Tho cc b phn chi tit truyn chuyn ng (qut gi, puli, bnh ai, tucnng, hp s...)- Tho np bch, hai gi .- Rt rto ra khi thn stato.- Lm sch v bo qun cc chi tit my

1.2. S tr dy q.S dy qun.

18765432110987654321

13

YX C

A B

U1~

4

1.3. T tp l tt.

Ly mu dy qun: Nu my in c thng s k thut ca nh ch to, thvic ly mu l khng cn thit, tuy nhin vn phi kim tra li xem thc t c


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ng chng loi vi gc nh ch to khng, trng hp khng c thng s nhch to, phi ly mu theo cc s sau:

Ghi li cc thng s trn nhn mc.o ng knh trong, ng knh ngoi, chiu di li thp...Xc nh s cc ca my, kiu qun dy, bc qun dy, s mch nhnh.

o chiu cao u b dy.Tho dy qun c, m s vng qun trn mt bi, s vng dy trn mtrnh v ng knh dy hiu dng c o bng panme ; Nu dy qun cnhiu si chp phi tnh s vng qun trn mt bi hoc trn mt rnh theos si chp ( khng b sai st khi qun v khi chn loi dy qun Thnghim.

V s tri b dy theo cc s liu bit.

1.4. T q dy.

1.4.1 Lt r tto .

Hnh 5.1: Rnh stato sau khi lm v sinh schGiy lt cch in gia cc bi dy vi rnh phi l loi giy dy, dai, t ht

m v c in p nh thng cao. l cc loi ba cch in chuyn dng, vila cch in thng, vi la cch in aming v cc loi giy mica. Chiu dyv vt liu lm lp cch in ph thuc vo in p lm vic ca ng c, cdy qun ng c v nhit ca n ch lm vic lu di. Nhn chung, ccng c cng ln th lp cch in cng dy v ngc li. i khi, tng chtlng cch in cho ng c, ngi ta phi lm lp cch in bng hai loi giylt, lp tip xc vi dy l lp chu nhit, lp tip xc vi rnh l lp chu inp. Khi qun li ng dy, cn phi cn c vo chiu dy lp cch in c lm


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giy lt mi. Nu giy lt mi m qu dy th khng th vo c ht dy, nuqu mng th d b r in ra li. Kt cu cch in rnh stato ng c xoaychiu c trnh by trn hnh 5.2.

a)

1

2

3

b)

Hnh 5.2. Kt cu cch in rnh stato ng c 1 pha chy ta) Cch in rnh dy qun xp n

b) Cch in rnh dy qun xp kp: 1 - Ba lt rnh, 2Ba p, 3Nm gCch lm ba lt rnh:a. Xc nh kch thc mu: ct ming ba cch in c chiu di ln hn

chiu dy ca li thp (4 6)mm. Chiu rng ly bng chu vi mt ct ngang carnh tnh t hai im gp ca ming rnh. Ct v gp mp hai u ming ba vmi pha (2 3)mm (tu ngc nh hay va m nn gp 2 hay 3mm). Lmnh th khi un u bi dy, giy cch in khng b x rch. Nn gp mpgiy ra pha ngoi chng khng chim ch ca bi dy (Hnh 5.3).

Lp

micacchinrnh

Lpgiycchinrnh

Hnh 5.3. Giy cch in lt rnh stato

b. Lng ming ba vo trong rnh ri dng mt long tre la vo rnh pming ba st vo thnh rnh. Long tre c mt ct ngang ng dng vi mt ctngang ca rnh, c chiu di ln hn chiu di ca rnh mt cht v khi t vornh phi gn kht (Hnh 6.9).


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Hnh 5.4. Dng long tre p ming ba lt st v thnh rnh

v stato hon tt cch in rnh ch lng dyc.Nu thy ming ba va vn vo rnh th ly lm mu ct cho ccrnh khc. Cn nu cha thy va th ly ra v iu chnh li, sau th li chon khi no c th thi.

Cch lm ba p

Hnh dng l mt hnh ch nht (c th ct vt bn gc) c chiu di phibng hoc di hn mt cht ba lt rnh sau khi gp mp, c chiu rng lnhn chiu rng ca rnh ti v tr p.

Lm nm

Vt nm vi mt ct c th l hnh thang hoc hnh bn nguyt, chiu dibng vi chiu di ca ba p. Chiu rng nn cn c vo rnh v khong trngcn tha ca rnh sau khi lng dy.Trong qu trnh lt cch in rnh chngta dng thanh tre y cch in tt st vch rnh. Sau khi lt xong ton bcch in rnh, chng ta kim tra cch in rnh phi m rng bung st vchrnh v khng c thp hn c rnh.

Ch :+ ba gy theo th ta nn ct ba cho mt gc 450 theo th caba.+ Nm tre th nn li phn ct, khi nm vo rnh th nn quay phn ct

ln pha trn.


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1.4.2. Q (y ) dy o t p dy q.

Hnh 5.5: Phng php nh kch thc cho chu vi dy qun Stato.

Hnh 5.6: Thao tc g cc dy ct gi cc cnh tc dng ca bi dy. Chtho dy ct ca mt cnh ca bi dy.


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Hnh 5.7: Thao tc cng hai u ni ca bi dy, tc dng lm ri cc vng dyca bi dy. Khi thao tc ch cng thng du dy v khng dng lc lm congu ni.

Hnh 5.8: Thao tc xi tng vng dy ca cnh tc dng ri ra sp song song;khng lm ri cc vng dy pha u ni. Thao tc thc hin trn cnh tcdng c g dy ct.


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Hnh 5.9: Tho tc g ri, sp song song cc vng dy pha u ni

1.4.3. L dy vo rnh stato.Trc khi lng dy vo rnh, cn nghin cu k s trn xc nh

khong cch lng dy v chiu lng, u dy. i vi nhng ng c mt phachy t iu ny l c bit cn thit v n gip ta ch ng bit c ng c squay theo chiu no. Khi lng dy phi tun th nguyn tc, cnh nm lpdi lng vo trc, cnh nm lp trn lng vo sau, bi dy nh lng votrc, bi dy ln lng vo sau. Cc bi dy khi qun trn khun thng b

phnh to chiu ngang ra mt cht, khi lng n bi dy no nn nn li bi dy cho ph hp vi khong cch gia hai khe ming rnh cn lng. Nu l ngc c rnh hnh thang th nn dng que tre, na vt nhn la dy khng nndng que kim loi v d bong, xc men dy. Khi u dy th da vo s ngang m u. Cc u dy ra nn chn v pha hp cc hoc gn l lun dy gip bi dy c gn gng. Cc mi dy ni phi m bo chc chn, tin cy.Trc khi ni, cn co sch cc u dy, xon li chc chn ri mi hn thic

bc ra bn ngoi. Tt c cc mi ni u c lng gen cch in bng cht chu

nhit (aming) chng nh xuyn ra cc bi dy bn cnh. Nu qun cc tbi dy theo kiu dnh i, dnh ba, dnh bn th s lng cc mi ni s cnrt t nhng khi lng dy hi kh mt cht v phi lng sao cho ng vi chiuni dy.


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Hnh 5.10: Dng giy cch in lt cnh dy ch, cha lng v rnh.

Hnh 5.11: Quay bi dy 1800 chun b lng dy vi rnh stato


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Hnh 5.12: Cng cnh tc dng gi song song cc vngdy khi lng dy.

Hnh 5.13: Thao tc lng dy v rnh


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Hnh 5.14: Thao tc xp song song cc cnh dy trong rnh dng cy mitSau khi lng dy xong cc vng dy vo rnh, chng ta cn lt giy nm

ming rnh gi cho cc vng dy qun lng vo rnh khng thot ra khirnh.

Hnh 5.15: a giy nm ming rnh t mt pha vo rnh.


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Hnh 5.16: y t t giy nm vo rnh

Sau khi lt xong giy nm ming rnh chng ta tin hnh lng dy ktip vo rnh.

Hnh 5.17: Chun b a bi dy k tip vo rnh stato. Thao tc ny thc hinsau khi xi v xp cc vng dy song song.


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Hnh 5.18: Quay 1800a bi dy v lng trong stato

Sau khi lng ton b dy qun vo rnh ( lng cc cnh dy ch vornh); chng ta lt cch in u ni gia tng nhm bi dy.

Cng on k tip l hn ni cc u dy ra ca cc cun dy. Bc gencch in cho cc mi hn ni gy ra. Dy gen bc phi di che ph mi hn v

dy dn cho n hc ra dy trn v ng cTrong qu trnh thi cng thc, chng ta cn dng nm tre nm gi cht

dy qun trong rnh. Nm tre phi c ng trn lp giy nm rnh. Khi nmrnh phi ng nm cn thn khng lm rch giy cch in rnh.

Sp xp cc dy ra gn gng, v dng bng ai vi, gi cht cc phn uni. Cng dng ca dy ai l xp gn u ni; gi giy cch in lp gia ccnhm. Phng php ai dy phi to cc gt c tnh cht m thut; thc hincho c hai pha u ni.

1.4.4. Lt , dy r v Khi bit chc chn cc mi ni c u chnh xc ri, ta tin hnh

ct b gn gng hai u ng dy li ri cho chy th. Nu dy qun ch c mtlp men, trc khi ct b nn dng ba mng lt vo ch u cc bi dy giln nhau chng nh xuyn t cun n sang cun kia.

Ct ming ba cch in thnh hnh vung sau gp cho gc thnh hnhtam gic v ct cc gc ln (theo hnh dng u b dy qun). Ming cch inc lt gia cc pha khc nhau, ngha l c cch mt nhm bi dy (t bi d y

bng q rnh) li t mt ci. C gng y ming cch in st xung sao chochm ti cch in rnh v ln trn cch in gia hai lp (nu l dy qun

xp kp). trnh ming ba b co ln khi ct b, ta nn x ming ba ti v trsi dy b.


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Sau khi lt ba cch in phn u dy xong th tin hnh ng nm mingrnh. Cch ng nm trnh by trn hnh 5.19. Trong qu trnh ng nm tre

phi cn thn trnh b rch ba p.

1 2

34

Hnh 5.19. ng nm vo ming rnh

1- Thanh g m; 2-Nm tre, g; 3 Ba p; 4Phn u cun dy

Cng vic tip theo l hn ni cc cc t bi li vi nha v hn cc u dy ara ngoi. i vi cc mi hn gia cc t bi th ng gen cch in phi clun su vo trong ming rnh. i vi cc dy ra, ng gen cch in phi diche ph mi hn v dn dn ra n l ra dy trn v ng c.

Dy dng ct b phi l loi dy chu nhit. Nu khng c dy chuyndng, c th dng loi dy khu u bao xi mng cng c. Xp xp cc udy gn gng v dng dy ai gi cht cc u ni. Cng dng ca dy ai lgi cht cc u ni, gi ba cch in phn u dy. Phng php bng b phi

to cc nt c tnh thm m v chc chn cho c hai u dy. Ch l khi bngb th bng b phn udy khng c cc mi ni trc. Hnh dng ca phnu dy sau khi bng b c trnh by trn hnh 5.20. Sau khi bng b xong,nn li cc u bi dy sao cho chng khng chm vo rto cng khng chmvo v v np y l c, sau chng ta lp rp hon chnh ng c, tinhnh o thng mch cc pha, o chm gia cc pha vi v v gia cc pha vinhau. Nu cch in t yu cu chng ta u vn hnh ng c v o dng inkhi ng v dng khng ti: xc nh phn trm dng khng ti, tnh i xnggia cc pha.


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Hnh 5.20. Phn u dy sau khi bng b

Hnh 5.21: Dy ai u ni

T y dy q:

Tm sy b dy qun l mt trong cc yu t quyt nh cht lng s dnglu di ca ng c in. Tht vy, nu mt ng c khng c tm sy chlm vic c 90C th khi c tm sy tt c th lm vic lu di c 105C. Tm sy tt s chng thm nc vo cc cun dy, chng m cho dy.Sn cch in s bt kn l rng nn tng kh nng tn nhit cho cc bi dy.

Tm sy cn lm tng in tr cch in v kh nng chu ng ca vt liucch in, tng sc bn c hc, sc chu mn. Sn lm cho cc u dy dnh


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cht li vi nhau nn t b nh hng v rung ng. Thc t cho thy, cc ngc c tm sy tt c tui th trung bnh tng ln gp ba n bn ln ng ckhng c tm sy. Sau khi tm sy, cc bi dy s tr nn rn chc, cho nnngi ta ch tin hnh tm sy sau khi bit chc chn ng c c qun lit yu cu. Trc khi tm sn cch in, ng dy rto hoc stato phi c sy

kh, sao cho khng cn hi nc bm xung quanh dy qun cng nh ba cchin v li tn silic. Sau , c th nhng ngp 2/3 ng dy vo sn cchin(nu c nhiu sn) hoc ti ln lt vo hai u ca ng dy (nu c tsn). Cui cng, tu theo loi sn cch in m cn phi sy li vi nhit vthi gian thch hp. Vi cc ng c ba pha, nu khng kim c loi dynhiu lp men, cn phi tm sy li ln th hai, th ba tng cng kh nngcch in cho dy qun. Nu khng c l sy chuyn dng, c th sy ng dng

bng cch, ng dy trong mt thng c np y kn t cch nhit vi t,dng mt bng n 200W t trc tip ln li thp rto hoc stato. Cch ny c

th t nhit sy n 100C. Vi nhng ng c ln, c th treo bng invo trong lng li thp stato ri y hai np ng c li. Ch , khng bngin tip xc trc tip vi dy qun.

1.5. T .Sau khi thc hin xong cc bc trn, chng ta lp rp hon chnh ng c

tin hnh o lin lc gia cc cun dy; o chm v vi cc cun dy qun. occh in gia cc cun dy.

Nu cch in t yu cu, chng ta u vn hnh ng c.Kim tra thng mch, kim tra cch in gia cc cun dy, gia cc cun

dy vi v, kim tra chp vng dy v cui cng l th t trng quay, nu ttc u tt th chuyn b dy sang cng ngh sn sy tm.

Nu cc bc trn hon tt v t yu cu: Khi thi cng thc chng ta phitho ri stato v rto sau tin hnh qui trnh tm sy cch in cho dy qun

2. Cc pan h hng v bin php khc phc.

* Nhng s c thng gp trong qu trnh qun l vn hnh ng c inHin tng s c Nguyn nhn Cch s l khc phc

1. ng c b nng

qu mc bnhhng khng c

im nng tprung. Ngoi rahng c hinng g khc.

Thng gi khng tt ( bi

bn tc ng thng gi,hoc qut gi b hng, qutgi quay ngc chiu)Du m vng ra ph vo dyqun Stato.ng c b qu ti.

ng dn nc lm mt b tchoc khng lu lng.

Lm sch ng thng gi,

sa li cnh qut gi.Lm v sinh cng nghiplau chi sch du , m bngxng cng nghip sau xy kh.Thng tht ng dn nc,kim tra my bm cung cpnc lm mt, sa chahoc thay mi t c

cc ch tiu thit k v lulng v ct nc.

2. Ton b li thp Thng gi khng tt. Tng cng thng gi cho


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v Stato b nngnhng ng ckhng b qu ti

C kh nng in p cali cao hn in p nhmc ca ng c

ng c bng cch lm vsinh, thng thong ngthng gi.

Kim tra in p li, nukhng sai khc in p nh

mc th phi thay ng cm3.Li thp Stato bnng tng mngngay c khi chykhng ti. in p nh mc.

Khi quay r to chm voStato hoc do cch in cctm tn Silic khng tt.

Bu lng p cht b stchm vi l thp.

Dy qun Stato b ngnmch, hoc cch in vi v

b nh thng lm ti bchy hng

Lm mt ch xc, qutsn cch in ln cc l tnSilc b chp. Cn chnh liv tr tng i gia R tov Stato hoc thay i ligi b mn

Dng M mt kim tra,

xc nh im h hng sacha li im b ngn mchhoc cun li cun dy Stato

4. Ton b dyqun Stato b nngqu mc bnhthng.

ng c b qu ti, haythit b thng gi b h hng.

in p t vo ng cqu thp so vi in p nhmc ca ng c .

u nhm cun dy Stato

Kim tra dng in Statogim ph ti h thng thnggi.

Tng lng in th ngunhoc gim ti .

u li cun dy Stato.5. Cun dy Stato

pht nng cc bqu mc bnhthng cng dng in ca cc

pha khng gingnhau ng c chin tng quaychm li, c tingku, p t mt ct.

Dy qun Stato b chpgia cc vng dy ca mt

pha.Cun dy Stato c 1 hoc

s bi u ngc u dy.Cun khi ng hoc

cun lm vic c in bchm v.

Qun li bi dy hoc thaybi dy mi.

Kim tra li xem chnh xcbi dy no b ngc uli cc t bi dy cho ng.

Dng Mmt hay n tmim b chm v sau sali ( cun li cch in, sntm...) hoc thay c bi dyc im b s c.

Kim tra bng M nunh th sa cha cch inim s c, nu cn thit thqun li cc pha b s c.

6. Lc vn hnh rto b ko lch vmt pha gy stct

Do gi trc b mnhoc t b ca gi trc khng ng Stato v Rto b bin dng trc b conglm cho khe h khng kh

khng u .Cn bng R to cha tt.

iu chnh khe h gia ctrc v ct xi n hoc thayct xi n mi, iu chnhkhe h gia r to v Stato,nu khe Stato b bin dng t

dng da st sa li, ch khng gy xc dy. Nu


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Trong dy qun Stato bchp gia vng dy hoc ccloi ngn mch khc

R to b bin dng nhiu cntin li, kim tra thngca trc.

Cn bng li R toDng tay kim tra s

pht nng cc b th hin ngoi v Stato. Dng Mv cu o in tr kim`tra thay i dy b hnghay u li dy qun Statocho ng.


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Bi 6: a cha ng c khng ng b ba pha

1. Tho v v sinh ng c.Cng tc chun b-Xc nh bin php tho c th-Chun b dng c tho ph hp, vt liu phc v tho lp, bo dng.-T chc ni lm vic thong rng, nh sng.Ghi chp tnh trng my trc khi tho-Quay trn, kp, st ct.-S nguyn vn ca cc chi tit.-Tnh trng k thut in.-S pht nhit, nhng h hng.- nh du lp rp: nh du lp rp v tr cn thit sau ny lp li khng bisai ln (v tr cc u dy, gi chi than, v tr mt bch, cnh qut, su

puli, bnh ai)Tho lp bo v cnh qut: Vi cnh qut dung vam hoc nm ba tho, gikhng lm bin dng cnh qut gy mt cn bng hay c xt khi my quay.- Tho Puli, bnh ai hoc khp ni: Dng vam chuyn dng ko tho (nnthm du vo v tr tip xc gia trc v puli trc khi tho). Trng hp khtho, nn dng bin php gianhit nhanh quanh bc puli bng n kh v vamko (ch : Qu trnh gia nhit bc puli phi lm mt c trc bng cch qun vi

Amian v thm nc).- Tho np m, np bch: Tho lp m bi trc, tho np bch sau. Nu my cchi than phi nng chi than ra trc, sau mi tho cc np bch. Khi tho npcn ni Bulong dn v u, dng ba c m g long dn cc np. Nu np pcht phi dng nm g by u, cng c khi phi dng vam ko.- Rt rto ra khi my: Vi my nh, dng tay nng nh rto ra khi stato, vimy ln nng phi dng xch treo, gi , ng lng trc h tr. Khi rt rto

phi ch :-Phi m k, khng c st, khng lm xc st dy qun.

-Khng lm bin dng, gy v cc chi tit lien quan (c gp, vnh trt, gi chi than, cnh qut) hoc gam xc c trc, b mt vnh trt

-Rto phi c t trn gi chc chn v sinh, kim tra, sa cha.Ra sach cc chi tit: cc chi tit my c ra sach bng xng hoc du ha vlau kh, sy kh sau khi ra. B phn dy qun nn dng hi kh nn thi bi

bn, trng hp b dnh du m nhiu phi ra th dng xng khng pha chhoc du nh ra sau sy kh ngay.Bo qun cc chi tit sau khi tho: cc chi tit sau khi tho c v sinh sch,nn nh s v bo qun bng khay, hp ring (vi cc chi tit nh). Nu cn

thit phi lu li ton b trn phiu sa cha v treo hp bo qun chi tit.


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2. ho st v v li s dy qun.

2.1.X l Trc ht, cn cn c vo kt cu ng dy, hnh thc khi ng, s u dy

ra, in p s dng khng nh l loi ng c g. T phn bit c

nhim v ca cc u dy ra v tm cch ghi nh chng bng mu sc v dy,bng nt tht hoc xu giy. Nu l ng c mt pha chy t th phi phn bitc u l u dy chung, u l u dy lm vic, u l u dy khi ng,u l u dy s (nu c). Nu l ng c ba pha th phi phn bit c u lu u ca cc pha, u l u cui ca chng, u l nhng

mi dy chung sau , phi dng s trn v li cu to ng dy.Cn phi v chi tit n tng bi dy sau ny c cn c m lng dy li

nh c. Nhng bi dy c lng vo trc hoc nhng cnh bi dy nm lpdi nn v bng nt t, nhng bi dy lng vo sau hoc nhng cnh bi dy lp trn nn v bng nt lin.Tip n, phi dng s ngang v li s u dy. Vi nhng ngc mt pha khng c cun dy s lptrong th v t mi dy chung v i,vi nhng ng c mt pha c cundy s lp trong th v t mi dylm vic v i. Cn vi nhng ngc ba pha th v t ba u dy uvo ba dy pha ca li in bn

ngoi v i. Cui cng, cn phn tchs u dy hiu c cch udy ca loi ng c . Khi chahiu c s u dy, tuyt ikhng c ph b ng dy hng.

Hnh 6.1 Vic u tin l tin hnh quanst cun dy, xc nh kiu qun, bcqun dy ct bng u dy, lt cc u

ni v li s tri

2.2. Tnh ton s liuB dy rto hoc stato trong ng c in thng c tm sn cch in

nn rt chc chn. Vi nhng ng c mi tip xc ln u li cn phi ly sliu na nn phi bit cch tho d n. Trc ht phi dng ca a hoc myct ct ct cc u ni v mt pha ca cc bi dy (Hnh 6.2). Cc mnh uni c ct ra cn phi gi li ly s liu.


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Hnh 6.2 Dng my ct ct ct cc

u ni mt pha

Hnh 6.3. Cc mnh u ni ct ra phi

gi li ly s liu

Tip n tng cho cc nm gi dy trt ra khi cc rnh, sau , dngtucnvit hoc que st, by cho phn cn li ca cc bi dy tt sang pha ngdy cha b ct (Hnh 6.4).

Hnh 6.4. Dng tucnvt, que st hocmc by cho phn cn li ca cc bi

dy tt sang pha cha b ct

Hnh 6.5. Li thp phi c v sinhsch s

i vi nhngng c ln, c th dng ba hoc t, t cho sn cch inbong ra ri tho dn cc vng dy ra khi rnh. Ring nhng ng c crnhhnh ch nht th khng nn ct u cc bi dy, nn dng ba v t g, g choc bi dy tt dn qua pha khe ming rnh. Khi ly s liu, nn g nh ln ccmnh u ni ct trn cho sn cch in bong ra, da vo mu men v cdy, ta m c s vng dy qun cho tng bi ca cc cun dy. trnhnhm ln, nn ly s liu ba mnh u ni khc nhau. S liu chnh thc sc ly mnh c s liu trung bnh. Vi nhng ng c dng lm qut bn

thng c cc cun dy s lng chung vi cun khi ng nn hi kh phnbit. Mun ly s liu c chnh xc th nn t chy ng dy ri d dn ccvng dy qua pha khe ming rnh ch khng ct u cc bi dy nh cch lm


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trn. Trng hp khng phn bit c bao nhiu vng thuc v dy khing, bao nhiu vng thuc v dy s th tm thi ly s vng ca mt cun s

bng t 1/4 n 1/3 s vng ca cun lm vic,s vng dy cn li s thuc vcun khi ng. Sau , qun th ri iu chnh dn cho hp l hn.

Sau khi tho d xong v ly c s liu th tin hnh v sinh li thp. Dng

que st hoc g y sch cc ming ba cn dnh trn li thp, sau dng khnn thi sch.2.1 S dy qun

V d : nh ton, v s tri b dy qun Stato ng c khng ng bxoay

chiu 3fa vi cc thng s nh sau:

Z1= 24, 2P = 4, m = 3, a= 1 dy q Xp p, .

+ Trc tin ta tnh tan cc thng s trn s tri

Bc cc: = Z1/2P = 24/4 = 6

S rnh di mt cc ca mt pha: q =2P.m

Z1 =4.3

24= 2

Bc qun dy: L dy qun xp, nn cc bi dy trong mt t bi c

cng chu vi, v vy ch c mt bc qun. Dy qun xp kp bc , ta

c bc dy qun y = = 6; n v ca bc cc c tnh l s

Khong cch, v vy ta c bc qun dy trong trng hp ny l y = 7rnh (T rnh 1 n rnh th 7).

Khong cch gia cc u u pha lin tip (th t pha):

ABC = 2.q + 1 = 5

* Trnh t v s tri nh sau

1:

Vch cc on thng song song, cch u th hin cc rnh ca li thpStato v nh s th t t 1 Z1(24 rnh); Dy qun xp kp nn mi rnh ca

li thp Stato trong trng hp ny c biu din bng mt ng nt lin v 1

ng nt t, th hin hai cnh lp trn v lp di ca mi rnh:


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2:

Phn vng cc cc v nh du chiu dng in trong cc rnh:

3:

Cn c vo bc qun dy, v cc bi dy, t bi dy ca pha th nht theo

nguyn tc:Mi bi dy c mt cnh nm lp trn ca rnh ny, cnh kia nm lp

di ca rnh khc, cch nhau bng bc qun y. Khi biu din cc Bi dy,

T bi dy ta v hai na ca mi bi dy theo k hiu cc rnh tng ng

Mt na bi dy nm pha trn ca rnh c v bng nt lin, na kia

c v bng nt t thuc v cnh nm lp di.

4:

Ni tip cc T bi dy ca pha th nht theo chiu dng in chn

trong cc rnh hoc theo quan h gia s cc v s T bi dy.


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Theo chiu dng in chn trong cc rnh th u cui ca T bi dy th

nht phi c ni vi u u ca T bi dy th hai.

Nu cn c vo quan h gia s cc v s T bi dy ta cng thy rng:

Ta c 4 T bi dy, m s cc ca my l 2P = 4( cc = t bi dy), vy

l ta phi s dng c t; Ngha l u cui ca T bi dy th nht

phi c ni vi u cui ca T bi dy th hai.

5:Bng cch tng t, ta v cc bi dy, T bi dy ca pha th 2.


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6:Xc nh rnh t u u ca pha CZ ri v nt cun dy CZ theo

cch tng t. Ti y ta hon thin c s tri cun dy qun Stato, dy

qun xp kp bc nh hnh v.

3. Thi cng qun dy.

3.1.Lt r tto .

Hnh 6.6: Rnh stato sau khi lm v sinh sch


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Giy lt cch in gia cc bi dy vi rnh phi l loi giy dy, dai, t htm v c in p nh thng cao. l cc loi ba cch in chuyn dng, vila cch in thng, vi la cch in aming v cc loi giy mica. Chiu dyv vt liu lm lp cch in ph thuc vo in p lm vic ca ng c, cdy qun ng c v nhit ca n ch lm vic lu di. Nhn chung, cc

ng c cng ln th lp cch in cng dy v ngc li. i khi, tng chtlng cch in cho ng c, ngi ta phi lm lp cch in bng hai loi giylt, lp tip xc vi dy l lp chu nhit, lp tip xc vi rnh l lp chu inp. Khi qun li ng dy, cn phi cn c vo chiu dy lp cch in c lmgiy lt mi. Nu giy lt mi m qu dy th khng th vo c ht dy, nuqu mng th d b r in ra li. Kt cu cch in rnh stato ng c xoaychiu c trnh by trn hnh 6.7.

a)

1

2

3

b)

Hnh 6.7. Kt cu cch in rnh stato ng c 3 phaa) Cch in rnh dy qun xp nb) Cch in rnh dy qun xp kp: 1 - Ba lt rnh, 2Ba p, 3Nm g

Cch lm ba lt rnh:

d. Xc nh kch thc mu: ct ming ba cch in c chiu di ln hnchiu dy ca li thp (4 6)mm. Chiu rng ly bng chu vi mt ct ngang carnh tnh t hai im gp ca ming rnh. Ct v gp mp hai u ming ba vmi pha (2 3)mm (tu ng c nh hay va m nn gp 2 hay 3mm). Lmnh th khi un u bi dy, giy cch in khng b x rch. Nn gp mp

giy ra pha ngoi chng khng chim ch ca bi dy (Hnh 6.8).


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Lp

mica

cch

in

rnh

Lp

giy

cch

in

rnh

Hnh 6.8. Giy cch in lt rnh stato

e. Lng ming ba vo trong rnh ri dng mt long tre la vo rnh pming ba st vo thnh rnh. Long tre c mt ct ngang ng dng vi mt ctngang ca rnh, c chiu di ln hn chiu di ca rnh mt cht v khi t vornh phi gn kht (Hnh 6.9).

Hnh 6.9. Dng long tre p ming ba lt st v thnh rnhv stato hon tt cch in rnh ch lng dy

f. Nu thy ming ba va vn vo rnh th ly lm mu ct cho ccrnh khc. Cn nu cha thy va th ly ra v iu chnh li, sau th li chon khi no c th thi.

Cch lm ba p


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Hnh dng l mt hnh ch nht (c th ct vt bn gc) c chiu di phibng hoc di hn mt cht ba lt rnh sau khi gp mp, c chiu rng lnhn chiu rng ca rnh ti v tr p.

Lm nm

Vt nm vi mt ct c th l hnh thang hoc hnh bn nguyt, chiu di

bng vi chiu di ca ba p. Chiu rng nn cn c vo rnh v khong trngcn tha ca rnh sau khi lng dy.Trong qu trnh lt cch in rnh chngta dng thanh tre y cch in tt st vch rnh. Sau khi lt xong ton bcch in rnh, chng ta kim tra cch in rnh phi m rng bung st vchrnh v khng c thp hn c rnh.

Ch :+ ba gy theo th ta nn ct ba cho mt gc 450 theo th ca ba.+ Nm tre th nn li phn ct, khi nm vo rnh th nn quay phn ct

ln pha trn.

3.2. Q (y ) dy o t p dy q.

Hnh 6.10: Phng php nh kch thc cho chu vi dy qun Stato.


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Hnh 6.11: Thao tc g cc dy ct gi cc cnh tc dng ca bi dy. Chtho dy ct ca mt cnh ca bi dy.

Hnh 6.12: Thao tc cng hai u ni ca bi dy, tc dng lm ri cc vng dyca bi dy. Khi thao tc ch cng thng du dy v khng dng lc lm congu ni.


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Hnh 6.13: Thao tc xi tng vng dy ca cnh tc dng ri ra sp songsong; khng lm ri cc vng dy pha u ni. Thao tc thc hin trn cnhtc dng c g dy ct.

Hnh 6.14: Tho tc g ri, sp song song cc vng dy pha u ni

3.3. L dy vo r tto.Trc khi lng dy vo rnh, cn nghin cu k s trn xc nh

khong cch lng dy v chiu lng, u dy. i vi nhng ng c mt phachy t iu ny l c bit cn thit v n gip ta ch ng bit c ng c s

quay theo chiu no. Khi lng dy phi tun th nguyn tc, cnh nm lpdi lng vo trc, cnh nm lp trn lng vo sau, bi dy nh lng vo


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trc, bi dy ln lng vo sau. Cc bi dy khi qun trn khun thng bphnh to chiu ngang ra mt cht, khi lng n bi dy no nn nn li bi dy cho ph hp vi khong cch gia hai khe ming rnh cn lng. Nu l ngc c rnh hnh thang th nn dng que tre, na vt nhn la dy khng nndng que kim loi v d bong, xc men dy. Khi u dy th da vo s

ngang m u. Cc u dy ra nn chn v pha hp cc hoc gn l lun dy gip bi dy c gn gng. Cc mi dy ni phi m bo chc chn, tin cy.Trc khi ni, cn co sch cc u dy, xon li chc chn ri mi hn thic

bc ra bn ngoi. Tt c cc mi ni u c lng gen cch in bng cht chunhit (aming) chng nh xuyn ra cc bi dy bn cnh. Nu qun cc t

bi dy theo kiu dnh i, dnh ba, dnh bn th s lng cc mi ni s cnrt t nhng khi lng dy hi kh mt cht v phi lng sao cho ng vi chiuni dy.

Hnh 6.15: Dng giy cch in lt cnh dy ch, cha lng v rnh.


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Hnh 6.16: Quay bi dy 1800 chun b lng dy vi rnh stato

Hnh 6.17: Cng cnh tc dng gi song song cc vng dy khi lng dy.


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Hnh 6.18: Thao tc lng dy v rnh

Hnh 6.19 Thao tc xp song song cc cnh dy trong rnh dng cy mitSau khi lng dy xong cc vng dy vo rnh, chng ta cn lt g

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