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Mc lc
Danh sch hnh v i
LI NI U. 1
1 GII THIU V TRUNG TM CTI. 21.1 Qu trnh thnh lp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.2 Chc nng ca trung tm.. . . . . . . . . . . . . . . . . . . . . . . . . . . 21.3 Nhim v ca trung tm. . . . . . . . . . . . . . . . . . . . . . . . . . . . 21.4 C cu t chc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31.5 Cc i tc. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 GII THIU CHUNG 42.1 B bin i iu chnh h s cng sut. . . . . . . . . . . . . . . . . . . . 42.2 Cc phng php iu chnh h s cng sut. . . . . . . . . . . . . . . . . 6
2.2.1 iu chnh h s cng sut tuyn tnh. . . . . . . . . . . . . . . . . 62.2.2 Tc dng ca b iu chnh h s cng sut PFC. . . . . . . . . . . 6
3 LA CHN CU TRC B BIN I V TNH TON MCH LC. 73.1 Yu cu thit k.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73.2 La chn cu trc mch v nguyn l lm vic. . . . . . . . . . . . . . . . 73.3 Tnh ton thng s cc phn t trong mch lc. . . . . . . . . . . . . . . . 10
3.3.1 Tnh ton t lc u ra. . . . . . . . . . . . . . . . . . . . . . . . . 103.3.2 Tnh ton in tr. . . . . . . . . . . . . . . . . . . . . . . . . . . 10
3.3.3 Tnh ton in cm.. . . . . . . . . . . . . . . . . . . . . . . . . . 103.3.4 La chn thit b ng ct. . . . . . . . . . . . . . . . . . . . . . . 11
4 THIT K B IU KHIN. 124.1 Phng php iu khin dng trung bnh. . . . . . . . . . . . . . . . . . . 124.2 Thit k b iu khin . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144.3 Thit k mch pht xung iu khin vi IC chuyn dng UC3854. . . . . . 18
4.3.1 Gii thiu v UC3854. . . . . . . . . . . . . . . . . . . . . . . . . 184.3.2 Chc nng v cch thit k cho tng chn ca UC3854 . . . . . . . 18
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5 KT QU M PHNG V THC NGHIM. 205.1 M phng bng phn mm Psim . . . . . . . . . . . . . . . . . . . . . . . 205.2 Kt qu thc nghim. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
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Danh sch hnh v
1.1 C cu t chc CTI.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
3.1 S cu trc b bin i Boost.. . . . . . . . . . . . . . . . . . . . . . . 83.2 M hnh khi kha S c thay bng MOSFETQ1v diodeD. . . . . . . . 8
3.3 S mch thay th a) MOSFETQ1ng, b) khi MOSFETQ1ct. . . . . 93.4 a) Dng sng in p trn cun cm, b) Dng sng dng in trn t in. . 93.5 Dng sng in p u ra.. . . . . . . . . . . . . . . . . . . . . . . . . . . 103.6 Dng sng dng in qua cun cm. . . . . . . . . . . . . . . . . . . . . . 11
4.1 S nguyn l ca phng php iu khin dng trung bnh trong mchboost PFC.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2 S mch vng dng in. . . . . . . . . . . . . . . . . . . . . . . . . . 144.3 th Bode ca vng dng in sau b. . . . . . . . . . . . . . . . . . . . 154.4 Cu trc b b loi 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
4.5 S mch vng iu chnh p. . . . . . . . . . . . . . . . . . . . . . . . 174.6 th Bode ca vng in p sau b. . . . . . . . . . . . . . . . . . . . . 174.7 A. Cu to bn ngoi. B Cu to bn trong ca UC3854. . . . . . . . . . . 18
5.1 Mch m phng bng phn mm PSIM 9.0. . . . . . . . . . . . . . . . . . 215.2 in p v dng in u vo. . . . . . . . . . . . . . . . . . . . . . . . . 215.3 in p v dng in u ra. . . . . . . . . . . . . . . . . . . . . . . . . . 225.4 Kt qu thc nghim mch thc. . . . . . . . . . . . . . . . . . . . . . . . 225.5 Kt qu o thc nghim trn Oscillocope. . . . . . . . . . . . . . . . . . . 235.6 Kt qu thc nghim khi ng ti. . . . . . . . . . . . . . . . . . . . . . . 23
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Chng 1
GII THIU V TRUNG TM CTI.
1.1 Qu trnh thnh lp.
Trung tm nghin cu ng dng v sng to cng ngh c thnh lp ngy 24/12/2009theo quyt nh ca hiu trng Trng i hc Bch khoa H Ni.
Trung tm vn hnh theo m hnh m, ni cc nh khoa hc v cc cn b nghin cuthuc nhiu lnh vc khc nhau c th cng lm vic v cng tc.
1.2 Chc nng ca trung tm.
Cc chc nng ca trung tm l:
iu phi hot ng cc phng th nghim trong trng i hc Bch khoa H Ni. Xc tin hot ng chuyn giao cng ngh v thng mi ha cc kt qu nghin cu
khoa hc ca Trng i hc Bch khoa H Ni.
Phi hp cc n v trc thuc B khoa hc, cng ngh v B gio dc, o to cngcc b khc thc hin cc nhim v khoa hc.
1.3 Nhim v ca trung tm.
Trung tm thnh lp nhm thc hin su nhim v c bn sau:
xut v thc hin cc ti nghin cu c kh nng ng dng thc tin. Thc hin cc ti v d n mang tnh lin ngnh. Gii m cc cng ngh tin tin nc ngoi v nhp khu vo Vit Nam. m to cng ngh v m to doanh nghip. m nhim cc hot ng bo tr, bo dng sn phm v dy chuyn sn xut.
o to v nng cao nng lc khoa hc cng ngh cho cc doanh nghip v t chc
khc.
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CHNG 1. GII THIU V TRUNG TM CTI.
Hnh 1.1: C cu t chc CTI.
1.4 C cu t chc.
Nhm thc hin cc nghin cu thuc cc lnh vc ln nh in t vin thng, cngngh thng tin, t ng ha, cng ngh vt liu,..b my t chc cn c c cu a dng vlin ngnh hnh1.1.
1.5 Cc i tc.
Trung tm hp tc vi nhiu t chc trong v ngoi nc trong lnh vc khoa hccng ngh:
Cc ng dng v pht trin cng ngh (SATI), B khoa hc cng ngh. Phng th nghim ca GS. Yoichi Hori, i hc Tokyo. Phn Lan trong chng trnh Innovation Patnership Program
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Chng 2
GII THIU CHUNG
2.1 B bin i iu chnh h s cng sut.
Hin nay trong hu ht cc thit b bin i in nng u s dng n chnh lu tngun xoay chiu (cung cp t li in) sang ngun mt chiu. Ngun in mt chiu sauchnh lu s ng vai tr l ngun cp cho tt c module bn trong ca thit b (k c ccmodule xoay chiu qua h thng mch nghch lu). Thng thng m bo c chtlng in p nh mong mun ta phi mc t san phng vi gi tr in dung ln vo ngaysau chnh lu. Chnh iu ny n n mt s vn cn phi c quan tm m in hnhl sng hi. Dng in vo t ngun li l dng gin on v tn ti trong nhng khongthi gian ngn (hi). S d c hin tng ny l do qu trnh phng np lin tc ca t lc.Thit b ch nhn nng lng t li trong thi gian t np. Khi cc hi ny c sinh ra
s gy hi n h thng li in. Tc hi ca nhng hi ny s cng ln khi cng sut tiln, hoc khi c ng thi nhiu thit b gy hi mc vo cng mt ngun li. Nh ta bit cht lng mt h thng cung cp in c nh gi bi hai (trong mt s) ch tiul h s cng sut (Power Factor - PF) v tng lng sng hi (Total Harmonic Distortion THD). Hiu nng ca h thng li in ph thuc rt nhiu vo yu t sng hi, tnglng sng hi cng nh hiu nng li in s cng cao.
H s cng sut (PF), theo nh ngha chung nht, l t s gia cng sut tc dng P vcng sut ton phn S:
PF= PS
(2.1)
i vi dng in v in p sin l tng th h s ny c dng n gin:
PF= cos (2.2)
Trong l gc lch pha gia dng in v in p, iu chnh h s cng sut chnhl iu chnh hay bcos
Trong thc t dng in v in p thng c dng sin khng l tng. H s cng sut
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CHNG 2. GII THIU CHUNG
theo cch hiu n gin khng cn ph hp v trong cc phn tch cng nh tnh ton phixut pht t nh ngha chung. d tnh ton mi dng in thc t c coi l tng cacc dng sin l tng, v mi dng sin thnh phn c gi l mt hi. Hi c tn s thpnht, bng tn s dng thc t, c gi l hi c bn, cc hi khc, c tn s cao hn, cgi l hi bc cao. Khi mc hay tnh cht sin ca mi dng in thc t c nhgi bng tng quan gia tng nng lng ca cc hi bc cao v nng lng ca hi cbn. Tng quan ny c gi l h s mo dng tng v thng c vit tt l TDH, l t s gia tr hiu dng ca tt c cc dng bc cao v tr hiu dng ca dng c bn:
THD=
n=2
I2n,hd
I1,hd(2.3)
Dng in c h s ny cng ln th c dng cng khc nhiu so vi sin l tng, dngsin l tng c THD=0. in p thc t cng c biu din tng t nh biu din dngin trn. Trong cc ng dng thc t in p v dng in c coi nh sin l tng nuh s mo dng tng khng ln hn 3%, tuy nhin theo tiu chun ca hip hi k thutin th gi tr ny l 2%. Nhn chung in p li tn s cng nghip chun, l trnghp c cp y, c coi nh c dng sin l tng. Khi , theo cch hiu hay nhngha chung nht v h s cng sut th cng thc 2.1c dng nh sau:
PF=UhdI1hdcos
UhdIhd=I1hd
Ihdcos= KpK (2.4)
Trong h s Uhd,I1hd,tng ng l tr hiu dng ca in p ngun, ca dng inc bn v gc lch pha gia dng in c bn v in p, h sKp=I1hd/IhdvK= cos.Quan h gia h s mo tng THD v h sKpc dng:
Kp= 11+THD2
(2.5)
Cui cng nhn c:
PF= KpK= 11+THD2
K (2.6)
Biu thc trn cho thy h s cng sut ph thuc vo thnh phn hi bc cao, gc lchpha gia dng in c bn v in p. Nh vy, dng in khng c dng hnh sin th h scng sut gm 2 thnh phn:
Thnh phn th nhtKl h s dch pha (displacement factor) lin quan n s lchpha gia in p v dng in. KhiKnh hn 1 iu ny c ngha l cng vi 1 titrng dng in s ln hn, gy tn tht ln hn trong b ngun v h thng ngunphn tn.
Thnh phn th haiKpl h s bin dng (distortion factor) lin quan n hnh dngdng in. KhiK
pnh hn 1 c ngha l s xut hin sng hi nhiu hn trong dng
in, n lm nh hng n ngun.
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CHNG 2. GII THIU CHUNG
2.2 Cc phng php iu chnh h s cng sut.
2.2.1 iu chnh h s cng sut tuyn tnh.
Trong thc t c kh nhiu cch iu chnh h s cng sut nhng ch yu c phn ratheo hai dng :
iu chnh h s cng sut th ng Passive PFC. iu chnh h s cng sut tch cc Active PFC.Hai phng php ny s c trnh by chi tit di y.
a) iu chnh h s cng sut th ng Passive PFC.
Phng php Passive PFC n gin ch l s dng mt b lc, b lc ny ch cho qua
dng in c tn s bng vi tn s in li (50Hz hoc 60Hz) v chn khng cho cc tns sng hi i qua. Lc ny ti phi tuyn tnh c th xem nh mt ti tuyn tnh, h s cngsut c nng cao hn.
b) iu chnh h s cng sut tch cc Active PFC.
L mt h thng in t cng sut c chc nng kim sot nng lng cung cp cho ti,iu chnh h s cng sut mc tt nht trn mi mc ti. Trong thit k thc t, mchActive PFC iu khin dng np cho ti sao cho dng sng ca dng vo cng pha vi dngsng u vo ( y l sng sin). V c bn c 3 dng mch Active PFC c s dng l:
Boost, Buck v Buck+Boost.
Phng php ny i hi phi thm mt s linh kin chuyn mch bn dn cng sut vmch iu khin nhng b li n c kch thc nh hn mch Passive PFC.
Dng mch iu chnh h s cng sut Active PFC c th hot ng trn mt di inp vo rt rng, t 90VAC n 264VAC, c tnh ny gip cho ngi dng khng cn quantm ti mc in p u vo, in p u ra n nh khi in p u vo bin ng.
2.2.2 Tc dng ca b iu chnh h s cng sut PFC.B PFC c lp t ti v tr gia ngun cp (sau chnh lu) v ti mt chiu, c tc
dng theo di h s cng sut ca ti v t ng iu chnh in p v dng in volun ng pha (cosphi = 1). ng thi n cn c tc dng n nh in p u ra, lm tngtnh n nh ca h thng, x l cc thay i din ra pha ngun cp v pha ti mt chiu,thng bo v tc ng khi xy ra s c. Gim gi thnh nng lng in v ph truynti.Gim thiu mt mt, tn hao trong truyn ti.Tng tnh cht in dung cho li in.
T nhng u im , n ny em thc hin v thit k b ngun AC/DC s dngphng php iu chnh cng sut tch cc.
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Chng 3
LA CHN CU TRC B BIN I VTNH TON MCH LC.
3.1 Yu cu thit k.
Gi tr in p hiu dng u voVin= 220(V). Tn s in p u vo l f=50(Hz). Gi tr in p u raVo= 400(V). Cng sut u raP=300(W).
Tn s ng ct f=100(kHz)
Tng thnh phn sng hi bc cao THD 15%. H s cng sut PF> 0.90 nhp nh dng in I= 10%Ipk
3.2 La chn cu trc mch v nguyn l lm vic.
Cu trc mch lc ca b ngun iu chnh h s cng sut thng c ba phn chnh:
Lc nhiu u vo EMI. Phn chnh lu khng iu khin. B bin i trung gian thc hin iu chnh h s cng sut. B bin i Active
PFC c s dng ph hp trong n ny l b bin i tng p Boost . Do yu cuthit k ra l gi tr in p hiu dng u voVin= 220Vv gi tr in p u raVo=400V, v vy ch c b bin i Boost l ph hp hn c. V b bin i Boost ccun cm c ni vi thit b u cui nn s c nhp nh dng in nh, dngin u vo c th t ch lin tc, gim thnh phn sng hi bc cao, gim kchthc b lc u vo. Do la chn b bin i Boost l em li hiu qu trong qutrnh thit k b ngun hiu chnh h s cng sut.
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CHNG 3. LA CHN CU TRC B BIN I V TNH TON MCH LC.
Hnh 3.1: S cu trc b bin i Boost.[1]
Hnh 3.2: M hnh khi kha S c thay bng MOSFETQ1v diodeD.[1]
Di y l nguyn l hot ng ca b bin i Boost:
Cu trc mch gm c in p u voVgvi chiu quy nh nh hnh3.1,cun khngL, vanSthc hin ng ct, t lc C, trong thc t ngoi thnh phn chnh l t Ccn cin tr ni tip tng ngRESR , ti trR, in p u ra c ly hai u t v(t),dngin qua cun cm iL(t)v t in iC(t). Do tn s chuyn mch cao fsw= 100kHznnkha S c th l cc van nh MOSFET Q1v diodeDnh hnh3.2.
Xt mt chu kTs: trong khong thi gian 0< t
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CHNG 3. LA CHN CU TRC B BIN I V TNH TON MCH LC.
Hnh 3.5: Dng sng in p u ra.[1]
3.3 Tnh ton thng s cc phn t trong mch lc.
3.3.1 Tnh ton t lc u ra.
Trong khong thi gian 0< t
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CHNG 3. LA CHN CU TRC B BIN I V TNH TON MCH LC.
Hnh 3.6: Dng sng dng in qua cun cm.[1]
cn trong khongDTs< t< Ts, dc dng in trn cun cm s l:
diL(t)
dt
=vL(t)
L
=VgV
L
(3.13)
S thay i dng in trong cun cm giai on 0< t
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Chng 4
THIT K B IU KHIN.
Nhim v ca mch iu khin l iu chnh ng ct MOSFET sao cho dng sng dng
in v in p l trng pha v in p u ra mt chiu n nh . V vy ta la chn phngphp iu khin dng trung bnh l ph hp trong thit k n ny.
4.1 Phng php iu khin dng trung bnh.
Nguyn l hot ng:
Phng php iu khin dng trung bnh c dng dng in u voILc o v tinhnh lc thng qua b b dng in. B b ny c tc dng lm gim sai lch gia dngin vo v I
re f. u ra ca b b dng in s c a vo module iu khin PWM
thc hin iu khin van ng ct. Phng php dng trung bnh cng thc hin ch dng lin tc nn c th thay th t yu cu cao hn.
u im: Tn s ng ct khng i. Khng cn b b dc.
Hnh 4.1: S nguyn l ca phng php iu khin dng trung bnh trong mch boost PFC.
[2]
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CHNG 4. THIT K B IU KHIN.
Do mch c vng iu chnh dng in nn t nh hng bi nhiu dn n yucu mch lc EMI b hn.
C dng dng in u vo tt hn ca phng php dng nh do phng php
dng trung bnh hot ng n nh hn khi dng in gn bng 0 nn hn chc gc cht ca dng in u vo.
Nhc im: Cn o dng in qua cun dy. Yu cu thit k b b dng in, cu trc mch phc tp.
Nhn thy phng php dng in trung bnh c nhiu u im khi iu khin cho mchBoost-PFC nh t c dng dng in u vo t bin dng, hn ch nhiu v nhpnh dng in trong mch. Tuy c hn ch song c th khc phc v iu khin tt. Chnh
v vy ta la chn thit k b iu chnh cng sut s dng mch Boost theo phng phpiu khin dng trung bnh.
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CHNG 4. THIT K B IU KHIN.
Hnh 4.2: S mch vng dng in.
4.2 Thit k b iu khinVic iu khin thc hin gm cc ni dung chnh sau:
Thng qua sai lch gia tn hiu u ra chun Vorefv in p u ra phn hi v thchin tnh ton a ra tn hiu iu khin in p Vcvi mc tiu iu khin in pu ra bng in p Voref. Trong n ny yu cu mch vng iu khin in p ara tn hiu iu khin in pVc iu khin in p u ra 400V.
Tnh ton dng in chun lm gi tr t cho mch vng dng in theo cng thc
sau:ire f=
VinVc
V2avg(4.1)
ViVavgl in p trung bnh u vo.
Thc hin mch vng iu khin dng in, c chc nng iu khin dngiLbm theodng in chun ire fc dng qu o bm theo qu o in p u vo nhm mcch t c h scos.
a) Mch vng iu chnh dng in.
Hm truyn mch vng dng in:
GiLd(s) =iL(s)
d(s)=
Vo(RCs+1)
LRCs2 +Ls+R(1D)2 (4.2)
Ti tn s cao, ta c th xp x gn ng mi quan h gia h s iu ch v dng intrung bnh qua cun cm nh sau (coi cun cm v t in l phn t l tng).[ 2]
GiLd(s) =iL(s)
d(s) VoLs
(4.3)
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CHNG 4. THIT K B IU KHIN.
Hnh 4.3: th Bode ca vng dng in sau b.
T th Bode ca i tng hnh4.3.La chn b b cho mch vng iu chnh dngin, h hi c d tr pha l 45o, tn s ct ca mch vng dng in fci= 20(kHz)v c im cc ti gc ta trit tiu sai lch tnh. Ta s dng b b loi 2 nh hnh4.4. T cu trc b b loi 2 nh trong hnh4.4hm truyn ca b b loi 2 c xc nhnh sau :
Gci= Kci(
s
wzi +1)s( s
wpi+1)
(4.4)
Kci= 1
Rf1(C1+C2) (4.5)
wz= 1
Rc1.Cc1(4.6)
wp= 1
Rc1.Cc12(4.7)
C12= Cc1.Cc2Cc1+Cc2
(4.8)
tha mn tiu ch thit k, b iu khin kiu b loi 2 cn tha mn phng trnh sau :Gci(jwc)Gp(jwc) = 1
arg(Gci(jwc)) +arg(Gp(jwc)) = m(4.9)
Gii h phng trnh 4.9 tm c cc tham s Kci,wzi,wpi. Da vo cc phng trnh 4.6,4.6, 4.7, gi tr cc phn t ca b b c xc nh bng cch chn trc Rf1
Rc1= 1wziCc1
(4.10)
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CHNG 4. THIT K B IU KHIN.
Hnh 4.4: Cu trc b b loi 2.[4]
Cc2= wzi
wpi.Rf1.Kci(4.11)
Cc1= 1
Rf1.KciCc2 (4.12)
Thay cc thng s vo tnh ton chn gi trRf1=3.9(k)t tnh c gi tr cc phnt ca b b 2 cho mch vng dng in R2= 22(k), C2= 100(pF)vC1= 470(pF).
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CHNG 4. THIT K B IU KHIN.
Hnh 4.7: A. Cu to bn ngoi. B Cu to bn trong ca UC3854[5]
4.3 Thit k mch pht xung iu khin vi IC chuyn dng UC3854
4.3.1 Gii thiu v UC3854.
UC3854 l IC thch hp cc phn t tng t trong cng mt v, vi chc nng phtxung PWM iu khin tn s cao trn 200kHz , cu to bn trong ca IC m bo y chc nng ca mt mch iu khin pht xung PWM, gip ngi thit k gim thiuthi gian tnh ton, thit k, d dng sa cha v thay th ti u ha mch nht. Hnh dngbn ngoi v cu trc bn trong v ca mt UC3854 nh hnh 4.7
Ngoi ra UC3854 l IC chuyn dng trong ng dng thit k b bin i cng sut iuchnh h s cng sut PFC , cho iu khin dng trung bnh, dng khi ng nh, nhiut. . . T cc tnh nng c bn trn vic la chn UC3854 cho vic thit k mch iu khinl hon ton hp l.
4.3.2 Chc nng v cch thit k cho tng chn ca UC3854
Sau y l bng4.1cc chn v chc nng ca tng chn:
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CHNG 4. THIT K B IU KHIN.
Bng 4.1: Cc chn v chc nng ca UC3854
Tn Chc nng
Gnd (chn 1) Chn t ca IC.PKLMT (chn 2) Gii hn dng nh, nuIpeakbng gi tr t th thc hinct duty.
CA Out (chn 3) u ra ca b b loi 2 vng dng in.Isense (chn4) u vo ca b b dng in. in p ri trn in tr s
c ni vi chn 4 v chn 5.IAC(chn 6) Ly dng sng u vo.VA Out (chn 7) u ra ca b b vng in p.VRMS(chn 8) Ly in p feedforward, gi tr ca n c bnh phng
trc khi cho vo b chia.REF(chn 9) u ra ca in p chun.ENA (chn 10) N cho php u ra PWM, in p chun v b dao ng
c hot ng hay khng.Vsense(chn 11) u vo ca b b vng in p.RSET(chn 12) v CT(chn 14) To tn s PWM. Theo datasheet ta c cng thc tnh tn
s PWM nh sau :
F= 1,25
RSET.CT(4.14)
Do ta chnRSET=10(k)v CT=1,2(nF).Vcc (chn 15) Chn ly in p nui ICSS (Chn 13) Khi ng mm gip bo v van khng b qu dng
giai on qu khi ta cp in p u vo, t khi ngc chn l 1(nF).
GT Drv (chn 16) u ra ca PWM ni vi MOSFET mch lc.
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Chng 5
KT QU M PHNG V THCNGHIM.
5.1 M phng bng phn mm Psim
Sau khi tnh ton mch lc v thit k b iu khin, ta tin hnh m phng. Thchin m phng trn phn mm PSIM 9.0 c s nh hnh5.1.Dng in p v dng in u vo c th hin hnh5.2.Dng in p v dng in
u ra c th hin hnh5.3
Da vo hnh5.2,hnh5.3ta c nhn xt: nhp nh dng t yu cu thit k ra ban u.
H s cng sut PF= 0.985cng t yu cu ra. in p u ra t c 400V.
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CHNG 5. KT QU M PHNG V THC NGHIM.
Hnh 5.1: Mch m phng bng phn mm PSIM 9.0.
Hnh 5.2: in p v dng in u vo.
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CHNG 5. KT QU M PHNG V THC NGHIM.
Hnh 5.3: in p v dng in u ra.
Hnh 5.4: Kt qu thc nghim mch thc.
5.2 Kt qu thc nghim.
Sau khi m phng ta tin hnh lm mch tht v kt qu t c nh hnh 5.4sau:T kt qu thc nghim mch tht o c trn Oscillocope nh trn hnh 5.5v hnh5.6th cho thy mch chy n nh vi100%ti nh mc , in p ra sau chnh lu (mu tm)v dng trn cun cm (mu vng) l cng pha do mch t c h s cng cng sut
coscao hn 90%
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CHNG 5. KT QU M PHNG V THC NGHIM.
Hnh 5.5: Kt qu o thc nghim trn Oscillocope.
Hnh 5.6: Kt qu thc nghim khi ng ti.
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