N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 1 Nhm Sinh Vin Thc Hin: Nhm 13 LI NI U Trong nhng nm gn y cng vi s pht trin ngy cng mnh ca cc lnh vc khoa hc, vic ng dng cng ngh bn dn vo b iu khin cc dn my cng nghip dn dn thay th cc loi relay tip im c in trc y v mang li nhiu thnh tu to ln. c bit lnh vc t ng ha ang c vai tr quan trng trong trong mi lnh vc cuc sng, n mang li nhiu li ch cho con ngi nh tng nng sut lao ng, gim thiu ti a lng cng nhn phi lm vic trong mi trng lao ng c hi. Trong phn ln cc nh my x nghip, cng nh phn xng u c s gp mt ca T ng Ha, trong cc dy truyn cng nghip N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 2 Nhm Sinh Vin Thc Hin: Nhm 13 MC LC LI NI U PHN 1. PHN DN NHP 1. t Vn . 2. Gii Hn Nghin Cu. 3. Mc ch Nghin Cu. PHN 2. NI DUNG THC HIN. CHNG 1. TNG QUAN V IN T CNG SUT. I. NHNG KHI NIM CHUNG V IN T CNG SUT. 1. Nhng Vn C Bn V in T Cng Sut. 2. Phm Vi ng Dng. II. GII THIU CC LINH KIN BN DN CNG SUT C BN. 1. DIODE. 2. TRANSISTOR. 3. THYRISTOR. 4. Kt Lun. CHNG 2. KHO ST MCH NG LC. I. Gii Thiu ng C in Mt Chiu V Cc Phng Php iu Chnh Tc 1. ng C in Kch T Song Song. 2. ng C in Kch T Ni Tip. 3. ng C in Mt Chiu Kch T Tng Hp. 4. Cc Phng Php iu Chnh Tc ng C in Mt Chiu. II. Gii Thiu Cc Phng Php o Tc . 1. Dng Phng Php o Bng C. 2. Dng Phng Php o Bng Cm Bin. III: Kt Lun. CHNG 3. THIT K MCH IU KHIN V B O TC . I. Thit K Mch iu khin ThyristorSCR. 1. Tnh Ton, Thit K Mch Nguyn L. 2. La Chn Linh Kin Mch iu Khin. II. Thit K Mch Kch Cho Transistor Cng Sut (Tip 41) S Dng Vi iu Khin AT89C51 V B o Tc . 1. Thit k phn Cng. 2. Thit k phn mm. CHNG 4. THIT K V THI CNG BO MCH PCB, M HNH N I. Thit K Bo Mch PCB. II. Thit k M Hnh n. CHNG 5. GII THIU PHN MM S DNG TRONG N. CHNG 6. KT LUN. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 3 Nhm Sinh Vin Thc Hin: Nhm 13 PHN 1. PHN DN NHP 1. t Vn . Vic chn n tp nghip mang mt ngha quan trng i vi mi sinh vin chuyn ngnh K Thut ni chung v chuyn ngnh Cng Ngh T ng ni ring. n c la chn sao cho ph hp vi trnh ca mi sinh vin m vn phi m bo bao gm khi qut chung nht v nhng kin thc hc ti trng. Vi chuyn ngnh T ng Ha nhng mn hc c coi l mang tnh thit yu phi k n nh: in T Tng T, in T Cng Sut, K Thut Lp Trnh VK 8501, PLC, My in T nhng phn tch trn m nhm chng em xin xut m hnh n tt nghip: O V IU CHNH TC NG C MT CHIU KCH T BNG NAM CHM VNH CU, HIN TH TC RA MN HNH LCD. Da trn nhng kin thc hc, m hnh do nhm em xut hon ton c th p ng c yu cu t ra. 2. Gii Hn Nghin Cu. M hnh mang ngin cu mang tnh thc tin, vic thi cng xy dng v lp t m hnh hon chnh c ng dng v mang tnh thc t cao. l mong mun ca nhm em khi xy dng m hnh ny. Tuy nhin vi lng thi gian v kin thc c hn, cng nh cc hn ch khch quan khc nn ti ca nhm khng th i su vo tng phng php iu khin tc ng c c m ch dng li ti phng php iu chnh ng c bng phng php thay i rng xung v phngphp iu p soay chiu mt pha... hay ni gn li l phng php iu chnh tc bng phng php thay i in p. Di y l nhng cng vic chnh m nhm chng em thc hin khi xy dng m hnh. -Kho st mch iu khin tc bng phng php thay i rng xung v phng php iu p soay chiu mt pha. -Thit k v thi cng m hnh trn l thuyt( tnh ton v la chn linh kin). -Thit v thi cng m hnh thc t. 3. Mc ch Nghin Cu. Vic s dng mn hc in t ng dng xy dng m hnh khng cn l hnh thc mi m, song iu mi m m nhm em hng ti y l: Gip cc bn sinh vin c ci nhn tng quan hn v in t ng dng v bit vn dng nhng kin thc hc trong nh trng ng dng vo thc t! N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 4 Nhm Sinh Vin Thc Hin: Nhm 13 PHN 2. NI DUNG THC HIN. CHNG 1. TNG QUAN V IN T CNG SUT. in nng l ngun nng lng sn xut trc tip v c ng dng rng di hin nay. Nhng trong thc t chng ta s dng ngun in chun l li in xoay chiu 220V/380V 50Hz. Mt khc trong cng nghip, cc thit b sn xut li s dng cc loi nng lng in khc nhau, c loi s dng in mt chiu, c loi s dng in xoay chiu vi cc cp in p khc nhau v tn s khc nhau. V c bit, iu khin hot ng ca cc thit b ta cn iu khin ngun nng in cp cho n. V vy, bin i v iu khin nng lng in l nhim v hng u tin phong trongt ng ha sn xut. Trc y vic bin i v iu khin nng lng in trong cng nghip ch yu s dng cc relay (r le), da vo vic ng m cc tip im ca relay m c ngun in mong mun. Tuy nhin, yu cu thc tin ngy cng cao ca sn xut cng vi s pht trin khng ngng ca khoa hc k thut cng ng bn dn cho php ch to c cc van bn dn (khng tip im) cng sut ln nhm thay th cc mch relay tip im trc y. V m ngnh IN T CNG SUT RA I! I. NHNG KHI NIM CHUNG V IN T CNG SUT. 1. Nhng khi nim chung v in t cng sut. a. Khi nim in t cng sut:cng ngh chuyn i v iu khin nng lng in t dng ny sang dng khc nh ng dng cc linh kin bn dn c cng sut ln. Cng sut in t: Trong mt lnh vc rng ln ca k thut in cng sut sut in t c th coi l t hp ca ba lnh vc: cng sut in t, in t, iu khin. Cng sut in t vi cc ng dng ca cc dng c na dn cng sut nh Thyristor v bn dn cho s bin i iu khin nng lng in ti cc mc cng sut cao, s bin i ny thng thng lt AC thnh DC trong thng s iu khin l in p, dng in hay tn s. Hnh 1: M T Cng Sut in T. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 5 Nhm Sinh Vin Thc Hin: Nhm 13 b.c im linh kin in t cng sut: + Pht trin cng ngh ch to linh kin bn dn c cng sut ln. + L thnh phn c bn ca cc b bin i cng sut tnh. + C hai ch lm vic: Lm vic ch ng, Ct. + C u im ln hn rt nhiu so vi kha c hc v bn vng, chnh xc v thi gian ng ct. + Thng s iu khin l: Dng in, in p, Tn s v tn hiu sng. c. Phn loi kha cng sut: - Theo c tuyn iu khin th c chia lm hai loi +Khng iu khin c c tuyn ng ct ( VD: Diode cng Sut). + iu Khin c trng thi ng ct bng tn hiu iu khin : (VD: Tranzitor, Thyristor,triac). - Theo chiu dng in chy qua: chia lm hai loi: + Mt chiu: Diode, BJT, IGBT,SRC, GTO: dn in theo mt chiu. + Hai chiu: MOSFET, SRC dn ngc, Diac, Triac: dn in theo hai chiu. - Theo kh nng kha p ngc tr s cao: Chia lm hai loi: + C kh nng: Diode, Thyristor, GTO, Triac + Khng c kh nng: BJT, IGBT. - Theo tn hiu iu khin: chia lm hai loi: + Tn hiu lin tc: BJT, IGBT, MOSFET: Mun duy tr trng thi ng phi duy tr tn hiu iu khin trong sut khong thi gian ny. + Tn Hiu xung: SRC, GTO, Triac: Tn hiu m l dng xung hp, khi kch m c th khng cn duy tr tn hiu iu khin cho n khi kha t ng nu tha mn iu kin ng. - Phn loi theo cc b bin i: chia lm 5 loi chnh. + B chnh lu: AC/DC :Bin i nng lng t dng xoay chiu thnh mt chiu c th iu khin c. + B bin i in p mt chiu: DC/DC: Bin i in p mt chiu vi u vo l c nh u ra c th iu khin c. + B bin i in p xoay chiu: AC/AC: Bin i in p xoay chiu vi u vo c nh u ra c th iu khin c. + B nghch lu: DC/AC : Bin i in p mt chiu thnh in p xoay chiu. + B bin tn: AC/AC hoc: AC/DC/AC:bin i in p u vo vi tn s khng i u ra tn s c th thay i( iu chnh c). N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 6 Nhm Sinh Vin Thc Hin: Nhm 13 2. Phm Vi ng Dng. in t cng sut c ng dng rng ri trong hu ht cc lnh vc c lin quan n bin i v iu khin cng sut in. H thng cng sut in c dng rng ri trong cc thit b cng nghip v trong dn dng,t cc ng c c cng sut nh di mt m lc dng trong cc dng c dn dng n cc ng c c cng sut vi trm m lc dng trong cng nghip. T iu chnh cng sut ng c mt chiu thp cung cp n h thng chuyn ti ng ccao p nhiu hn mt ngn Megawott, t cc h thng iu chnh nh sng cng sut thp n cc c cu b tnh AVR cng sut hng trm Megawatt trong cac h thng cng nghip. Di y l mt vi phm vi ng dng ca in t cng sut: Bng1: Mt vi ng dng ca in t cng sut. STTChuyn i cng sutCc ng dng 1Chnh lu khng iu khin Cung cp ngun mt chiu cho cc mch in t. 2Chnh lu c iu khin - iu khin tc ng c DC t ngun AC. - iu khin tc ca cc dng c cng sut xch tay. - Truyn ti dng DC cao p. 3Mach bm DC- iu khin tc ng c DC t ngun DC. - Chuyn mch DC cung cp. 4iu khin in AC- Chuyn mch dng c iu chnh nh sng. - iu khin nhit . - iu khin tc cc dng c gia dng. - Lm m khi ng ca cc ng c cm ng. - phn ng cng sut iu khin.5Mch i in-Cung cp cng sut lin tc (UPS). - iu khin tc ng c ba pha. - Cm ng nhit. 6Mch i in chu k- iu khin tc ng c AC. - Ngun tn s khng i cho my bay. 7Chuyn mch tnh hc Thay th chuy mch c kh v in t. II. GII THIU CC LINH KIN BN DN CNG SUT C BN. thc hin vic ng ct in t bng cc van bn dn cng sut ta c th s dng nhiu linh kin hay nhm linh kin bn dn cng sut chu c p cao dng ln v quan trng nht phi tha mn c hai ch : - Dn in (ON): st p qua knh dn b, dng in ph thuc vo dng ti. - Kha (OFF): Dng qua n rt b (0), knh dn in coi nh l h mch. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 7 Nhm Sinh Vin Thc Hin: Nhm 13 Cc loi van bn dn chnh phi k n nh l: Diode, Thyristor, Transistor ngoi ra cn mt s loi thng dng nh: Mosfet, Triac, Diac, GTO, IGBT Sau y l phn gii thiu v 3 linh kin bn dn chnh: DIODE, TRANSISTOR, THYRISTOR. 1. DIODE. a. Cu to v c im: Hnh 2: Diode Cng Sut a)Cu trc bn dn b)K hiu c)cc dng v ca diode Cu to: Diode c cu to n gin, bao gm: Mt lp chuyn tip P-N, bn ngoi c gn 2 in cc. Cc Anode ni vi lp P, Cc Cathode ni vi lp N. c im: - y l loi linh kin khng iu khin c. - Qu trnh ng ngt: AKV> 0, (in p Anode dng hn in p Cathode) th Diode dn(ng), ngc li diode kha (Ngt). - Tip din ca phin bn dn Si quyt inh n kh nng chu n ca Diode. - in tr ca nguyn liu ban u (VD: phin bn dn loi N) v chiu dy quyt nh n kh nng chu p ca Diode. - Mt s tham s c Bn:+ Kh nng iu khin dng in ( vi A n kA). + Kh nng iu khin in p ( vi chc V n kV). N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 8 Nhm Sinh Vin Thc Hin: Nhm 13 + Thi gian phc hi tnh nghch: Thi gian cn thit Diode phc hi kh nng chu p kha khi qu trnh dn thun chm dt chia lm hai loi: Thi gian phc hi nhanh: c s dng trong cc mch c tn s cao; Thi gian phc hi chm: c s dng trong cc mch c tn s thp, ch yu l trong cng nghip. b. c tuyn vn- ample (V - A) v c im ng ngt: c Tuyn V A Hnh 3: c tuyn V A ca Diode. Cc tham s chnh: TOU: in p ng Diode ( Turn - On). BRU : in p ngc nh thng lp PN ( Break - Down). UffIfdRd=: in tr vi phn thun. UrrIrdRd= : in tr vi phn nghch. c im ng ngt: Khi Diode dn n tng ng vi mt cng tc ng, in p ri trn linh kin nh dng thun qua linh kin ln. Khi Diode ngt n tng ng vi mt cng tc ngt. in p kha ln, dng r qua linh kin rt b. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 9 Nhm Sinh Vin Thc Hin: Nhm 13 u im chnh ca Diode: C kh nng chu p ti v dng ti ln, C th gp ni tip cc Diode tng kh nng kha p, hay gp song song tng kh nng chu dng ti. V c ng dng rng ri trong cng nghip vi cc thit b yu cu tn s ng ngt cao, ngoi ra cn c ng dng trong cc mch s dng in p thp chnh lu 2. TRANSISTOR. a. Cu to c im: Hnh 4: Cu to ca Transistor. a: Cu trc bn dn. b: K hiu. c: Hnh dng bn ngoi. Cu To: Transistor c cu to gm ba lp bn dn gp vi nhau to thnh hai lp bn dn P-N, gp theo kiu P-N-P ta c Transistor thun, cn gp theo kiu N-P-N ta c Transistor ngc. cn v phng din cu to c th coi nh Transistor bao gm hai Diode ni ngc chiu nhau to ln. Ba lp bn dn c gp vi nhau to thnh ba cc. Lp gia gi l cc gc, k hiu l B (base) lp B rt mng c nng tp cht thp. Hai lp bn ngoi c ni thnh cc pht (Emitter) vit tt l E v cc thu (Collecter) k hiu l C. Vng bn dn C v E c cng loi bn dn N hoc P nhng kch thc v nng tp cht khc nhau ln khng th hon i cho nhau c. c im ca Transistor: + Transistor lm vic nh mt kha ng ct bn dn c s dng trong in t cng sut ln Transistor ch lm vic ch ng v ngt. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 10 Nhm Sinh Vin Thc Hin: Nhm 13 + Transistor c inh mc ti 1200V 400A, v chng thng c s dng trong cc b bin i vn hnh c tn s ti 10kHz. Transistor c cng sut inh mc cao hn MOSFET + Khng c kh nng kha p ngc tr s ln Chuyn dng kha p thun (Vce > 0) + Transistor l loi linh kin iu khin bng dng, C h s khuc i thp, thng nh hn 20 ( < 20) CFEBIHI= , (FEH < 20) b: c tuyn Vol Ampe ( V - A ). Hnh 5: c tuyn Vol Ampe Ca Transistor. - c tuyn V A Biu th mi quan h gia dng trn cc Collector Vo p gia hai cc cng sut Vce ph thuc tham s iu khin l dng Ib - Hai vng lm vic ng vi trng thi ng ngt ca Transistor: Vng ngt v vng bo ha. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 11 Nhm Sinh Vin Thc Hin: Nhm 13 c: Thng s k thut v k hiu ca Transistor. Thng s k thut. + Dng in cc i: L dng in gii hn ca Transistor, nu vt qu gi tr ny Transistor s b hng. + in p cc i: L in p cc i t vo cc CE, nu vt qu gi tr ny Transistor s b nh thng ( Hng). + Tn s ct: L tn s gii hn m Transistor lm vic bnh thng, nu vt qu gi tr ny th h s khuc i ca Transistor s gim. + H s khuc i: L t s bin i dng Ice ln gp bao nhiu ln dng Ibe. + Cng sut cc i: Khi hot ng Transistor tiu tn mt lng cng sut: P=Uce*Ice Nu cng sut ny vt qu cng sut cc i ca Transistor th Transistor s b hng. K hiu ca Transistor. Hin nay trn th trng c nhiu loi Transistor ca nhiu nc sn xut nhng thng dng nht l cc transistor ca Nht bn, M v Trung Quc. Transistor Nht bn : thng k hiu l A..., B..., C..., D... V d A564, B733, C828, D1555 trong cc Transistor k hiu l A v B l Transistor thun PNP cn k hiu l C v D l Transistor ngc NPN. Cc TransistorA v C thng c cng xut nh v tn s lm vic cao cn cc Transistor B v D thng c cng xut ln v tn s lm vic thp hn. Transistor do Trung Quc sn xut : Bt u bng s 3, tip theo l hai ch ci. Ch ci thc nht cho bit loi bng : Ch A v B l bng thun , ch C v D l bng ngc, ch th hai cho bit c im : X v P l bng m tn, A v G l bng cao tn. Cc ch s sau ch th t sn phm. Th d : 3CP25 , 3AP20 vv Transistor do M sn xut: Thng k hiu l 2N... v d 2N3055, 2N4073 vv... N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 12 Nhm Sinh Vin Thc Hin: Nhm 13 3. THYRISTOR. a. Cu to v c im hot ng ca SCR Cu to: Hnh 6: Cu to ca Thyristor (SCR). a: Cu trc bn dn. b: K Hiu. c: Hnh dng thc t. d: Cc mc SCR t Transistor. Thyristor c cu to gm 4 lp bn dn ghp li to thnh hai Transistor mc ni tip, mt Transistor thun v mt Transistor ngc ( Hnh 6 d ) .Thyristor c 3 cc l Anot, Katot v Gate gi l A-K-G. Thyristor l Diode c iu khin , bnh thng khi c phn cc thun, Thyristor cha dn in, khi c mt dng din iu khin kch vo chn G => Thyristor dn cho n khi in p o chiu hoc ct in p ngun Thyristor mi ngng dn. c im hot ng ca SCR: - Dng cho mch cng sut ln yu cu iu khin tn hiu in p ra( Nh mch chnh Lu c iu khin, iu p soay chiu,) - Mch iu khin ni gia cc G K, mch cng sut ni gia A K. - SCR c iu khin bng xung dng, Xung dng Ig kch ng SCR. - Khng cn kch ngt, dng qua SCR ang d If b ngt khi dng fInh hn dng duy tr hI(f hI I = < bt u kch xung m cho van bn dn cng sut. Vy trong khong t0dkU c gi l gc iu khin (k hiu: ). Hnh 25: Dng sng m t cc khu trn hnh 24. I. Thit K Mch iu khin ThyristorSCR. 1. Tnh Ton, Thit K Mch Nguyn L. Mch iu khin Thyristor bao gm bn khi chnh: - Khi mch ngun. - Khi to in p iu khin. - Khi cch ly xung v khuc i xung. - Khi mch lc N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 28 Nhm Sinh Vin Thc Hin: Nhm 13 a. tnh ton khi ngun. Hnh 26: S khi khi ngun. Nguyn l lm vic: in p xoay chiu c a vo b chnh lu, b chnh lu c nhim v bin i dng xoay chiu thnh dng mt chiu. in p sau khi chnh lu c a vo b lc, b lc c nhim v lc in p sau chnh lu thnh( san phng in p). Sau khi in p c lc th c a vo b n p n nh mc in p ra mt gi tr nht nh. S mch nguyn L khi ngun. Hnh 27: S nguyn l mch ngun. Tnh ton in p sau khi qua DIODE cu u ra sau Diode c tnh theo cng thc sau: ( )2out inU U K = (3.1) outU:in p sau Diode cu. inU :in p sau my bin p K : H s st p trn Diode (K=0.45) p dng vo mch ta c: ( )2out inU U K == (12*0.45)*2=10.8V Chn C5, C6, C7, C8 Nh Hnh 27 m bo lc in p. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 29 Nhm Sinh Vin Thc Hin: Nhm 13 Gi tr R1 c xc nh theo cng thc: 1( 1)LEDLED LEDU ERI U= (3.2) LEDU: in p ri trn n LED (LEDU =3V) . LEDI : Dng in chy qua LED (LEDI =0.0015A). E: in p ngun (E = 12V) => 13 12( 1) ( 1) 60000.0015 3LEDLED LEDU ERI U= = = O Trn thc t k c in tr 6K ln ta chn loi in tr 6k2 b. Mch iu khin: Hnh 28: S khi iu khin. in p T c a vo IC TCA 785. Qua TCA 785 vi s bin thin ca in p dkUs cho ra xung iu khin tng ng, Trong khi ny bao gm hai phn chnh: + To in p ta + To in p iu khin b1: To in p ta: Hnh 29: To in p ta. Chn 2Rsao cho mch khng b on mch, chn 2R = 22k. b2: To in p iu khin N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 30 Nhm Sinh Vin Thc Hin: Nhm 13 to mch kch cho SCR trn thc t c rt nhiu phng php: nh l s dng cc khu bin i dng OP,hay dng IC TCA785 Cc khu bin i dng OP c s phc tp, tnh ton nhiu, cho kt qu sai s nhiu bn cnh vic s dng IC TCA785 li n gin hn nhiu n kt bn khu to dng xung iu khin ca OP trong mt. Tm hiu v IC TCA785 Cu trc bn trong IC TCA785. Hnh 30: Cu trc bn trong ca TCA785. M t chc nng ca TCA785 Tn hiu ng b c c qua tr khng cao t in p dy (V5). B pht hin in p khng s xc nh cc in p khng v chuyn chng n thanh ghi ng b. Thanh ghi ng b ny iu khin b to dc (lm dc xung tn hiu iu khin), t C10 trong b to dc c np vi dng c nh (xc nh bi R9). Nu in p dc N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 31 Nhm Sinh Vin Thc Hin: Nhm 13 (in p rng ca, tam gic) V10 vt qu in p iu khin V11 (gc m ) th tn hiu in chuyn thnh dng Logic ph thuc vo ln ca in p iu khin V11 m gc m c th c dch chuyn trong khong t (0=> 180) Vi mi phn sng mt xung dng c 30s li xut hin cc u ra Q1, Q. Gi s tn ti xung c th t 180 qua t C12. Nu chn 12 ni mass cc xung trong khong gc (0 => 180) s xut hin. Cc u ra1, 2 cung cp tn hiu ngc vi Q1, Q2. Tn hiu ti +180 c th c dng iu khin mt b Logic ngoi c ti chn 3. Mt tn hiu tng ng vi lin kt NOR ca Q1, Q2 c sn ti ca Qz (chn 7). Cng vo hn ch c th c dng loi tr hot ng ca cc cng ra Q1,Q2Chn 13 c th dng m rng cc u ra1, 2 nhm lp y rng xung (180 - ). Bng 2: K hiu v nga ca cc chn trong TCA785. Thng sK hiuGi tr gii hnn v MinMax in p cung cpVS- 0.518V Dng in ra ti chn 14, 15IQ- 10400Ma in p gii hnV6 - 0.5VSV in p iu khinV11- 0.5VSV in p ngn xungV13- 0.5VSV Dng in vo ng bV5- 200200A in p ra ti chn 14, 15VQVSV Dng ra ti chn 2, 3, 4, 7IQ10Ma in p ra ti chn 2, 3, 4, 7VQVS V Nhit tip gip Nhit ct gi TJ Tstg - 55150 125 0C 0C Tr nhit h thng mi trngRth SA18K/W N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 32 Nhm Sinh Vin Thc Hin: Nhm 13 Bng 3: Thng s ca TCA785 Thng sK hiuGi tr gii hnn v MinMax in p cung cpVS- 0.518V Dng in ra ti chn 14, 15IQ- 10400Ma in p gii hnV6 - 0.5VSV in p iu khinV11- 0.5VSV in p ngn xungV13- 0.5VSV Dng in vo ng bV5- 200200A in p ra ti chn 14, 15VQVSV Dng ra ti chn 2, 3, 4, 7IQ10Ma in p ra ti chn 2, 3, 4, 7VQVS V Nhit tip gip Nhit ct gi TJ Tstg - 55150 125 0C 0C Tr nhit h thng mi trngRth SA18K/W Biu xung ca TCA785 Hnh 31: Biu xung ca TCA785. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 33 Nhm Sinh Vin Thc Hin: Nhm 13 S nguyn l theo Datesheet. Hnh 32: Mch nguyn l theo s Datasheet. S nguyn l sau khi rp mch theo mch Datasheet. Hnh 33: Rp mch nguyn l theo Datasheet. c: Khi Cch Ly v khuc i xung. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 34 Nhm Sinh Vin Thc Hin: Nhm 13 Vic cch ly xung v khuc i xung c s dng thng qua cch li quang c1: Tm hiu v cch li quang (PHOTODIODE) Hnh 34: Cu to Photodiode. Nguyn l lm vic: Tn hiu iu khin c mc vo chn 1, chn 2 ni vi in tr R ng vi trng thi 1 ca tn hiu iu khin n LED trong Photodiode s pht sng, cm bin quang NPN trong cch li quang s thng mch cho dng chy qua, nu chn s 4 mc vi ngun dng E => ng vi mi trng thi 1 ca tn hiu iu khin th trn chn s 3 s c tn hiu iu khin +E tng ng. Cc loi Cch li quang thng dng trn th trng hin nay l: OPTO TLP521_1, TLP521_2, TLP521_4, OPTO PC817 c2: Rp mch nguyn l: Hnh 35: S nguyn l cch rp cch li quang. d: Khi mch lc Hnh 36: Khi mch lc N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 35 Nhm Sinh Vin Thc Hin: Nhm 13 V y l mch iu p soay chiu mt pha, trong khi ti ca ta l ng c mt chiu v vy sau khi iu p xong chng ta cho qua mt chnh lu cu ta s nhn c in p mt chiu. 2: La Chn Linh Kin Mch iu Khin. Sau qu trnh phn tch mch trn ta s rp c s nguyn l mch iu khin cho Thyristor nh sau: Hnh 37: S mch kch SCR s dng TCA785 N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 36 Nhm Sinh Vin Thc Hin: Nhm 13 Bng 4: S lng linh kin cn thit cho vic rp mch STTLoi Linh kinS Lng (Ci) Ghi Ch TnK HiuGi Tr 1in trR1K4Tr thng 4K72 6K21 10K1 22K1 2Bin trR1K1 100K1 3T inCC1032T gm C1041 1000uF-25V2T ha 4Diode1N40076Diode thng 5Chnh lu cuBR2A1Diode cu Thng3A1 6ThyristorBT1512Mch Lc 7Cch ly quangTLP521_12Opto 8IC NgunLA78121IC Ngun 9IC TCA785TCA7851 10CON-H2J4Gic cm II. Thit K Mch iu Khin Cho Transistor Cng Sut (Tip 41) S Dng Vi iu Khin AT89C51 V B o Tc . 1.Thit k phn Cng. a:Thit K Mch Kch Cho Transistor Cng Sut (Tip 41) a1:Khi Ngun. Hnh 38: S mch ngun N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 37 Nhm Sinh Vin Thc Hin: Nhm 13 p dng kt qu trong chng 3- phn 1 - a ta tnh c gi tr ca R1 13 5( 1) ( 1) 1333.30.0015 3LEDLED LEDU ERI U= = = O Nhng trn thc t khng c in tr 1K3 vy ta chn R1=1K6. b: Khi iu khin: Tm hiu v phng php iu ch PWM. PWM l cm t vit tt ca Pulse Width modulation y l phng php iu chnh in p ra ti. Hay ni mt cch khc PWM l phng php iu ch rng xungda trn s thay i rng chi xung vung ra dn n s thay i in p Nguyn l hot ng: Trong khong thi gian t 0 ta cho van G m ton b in p ngun dUton b in p c a ra ti, cn trong khong thi gian ot T ta cho van G kha, ct ngun cp cho ti, t ta tnh c in p trung bnh ra ti theo cng thc sau: 1max( )dtU UT=V(3.3) t 1tDT==> max dU U D = (3.4) Vi D l h s diu chnh v c n v l %. Nh vy c ng vi mi gi tr ca D ta s c mt in p max dU U s Vd: Tnh dU ng vi cc gi tr ca D=20%, D=40%, D=90% v max12 U V = 12*20% 2.4dU V = =ng vi D=20% 12*40% 4.8dU V = =ng vi D=40% 12*90% 10.8dU V = = ng vi D=90% Trn thc t to ra xung iu khin PWM th c 2 cch thng dng: bng phn cng v bng phn mm. Phn cng c th to ra nh phng php so snh hay s dng trc tip IC dao ng IC555, LM556 Trong phn mm c th to ra bng cc chp c th lp trnh c. u im khi to PWM bng phn mm, cho chnh sc cao, c mch nguyn l n gin. V vy trn thc t ngi ta ch yu s dng phn mm to xung iu khin PWM. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 38 Nhm Sinh Vin Thc Hin: Nhm 13 Mch nguyn l: Hnh 39: Mch iu ch PWM Rp mch nguyn l theo Datasheet. Nguyn l lm vic ca mch: Tn hiu in p dkUc to ra nh mch phn p s dng bin tr thay i gi tr, tn hiu c a vo chn s 6 ca b ADC(*). Thng qua b ADC chuyn tn hiu iu khin thnh dng s ri a vo VDK 805. VK nhn tn hiu v cho kt qu ra chn s 10. ng vi mi gi tr dkUtng th t l D tng. (0100%)maxU . (*): ADC l b chuyn i t tng t sang s. Trong mch s dng IC ADC0804. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 39 Nhm Sinh Vin Thc Hin: Nhm 13 c: Khi mch lc Hnh 40: S mch lc iu ch PWM. Tn hiu iu khin qua OPTO c cch ly gia xung iu khin vi ngun mch lc. in p trn ti c iu khin bng Transistor cng sut Tip41. Dng xung iu khin l dng in p trn ti. II: Thit k mch o tc . B o tc bao gm 3 khi chnh: Khi mch ngun. Khi tnh ton v hin th. Khi Encoder. a:Khi mch ngun: S dng in p mt chiu 5V, v c ly ngun nui t Khi PWM. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 40 Nhm Sinh Vin Thc Hin: Nhm 13 b:Khi tnh ton v hin th Mch nguyn l Hnh 41: S nguyn l o tc . Nguyn l lm vic: Tn hiu in p t Encoder c a vo chn 14 ca VK thng qua vic tnh ton trong VK kt qu c hin th ra mn hnh LCD. Bin tr RV2 dng khin sng mn hnh LCD. Cng tcBT dng restar VK t C3 c nhim v chng dung c hc. in tr R2 dng hn ch ngn mch. c: Khi ECODER S nguyn l: Hnh 42: Cu to ENCODER. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 41 Nhm Sinh Vin Thc Hin: Nhm 13 Encoder c cu to n gin: Bao gm Mt LED pht v Mt LED thu (cm bin quang), v mt OP. Nguyn l lm vic: khi cp 1 in p +E vo LED pht => n LED D4 sng. Cm bin Quang (LED thu) nhn tn hiu anh sng cho Ngun +E i qua,tn hin +E c a vo OP TL082 so snh vi GND (tn hiu t = 0) y l kiu so snh khng o, => chn s 1 ca OP cho ra mt in p xung vung vi Bin l +E. tn hiu ny trc tip c a vo VK thng qua IC logic NOT. III: La chn linh kin rp mch Sau khi gp cc khi li ta c s hon chnh ca khi PWM v o tc Hnh 43: Mch Nguyn l PWM v o tc ng c. N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 42 Nhm Sinh Vin Thc Hin: Nhm 13 Bng 5: S lng linh kin cn thit cho vic rp mch: STTLoi Linh KinS Lng (Ci) Ghi Ch Tn Linh KinK HiuGi Tr 1in TrR2K21Tr thng 10K5 2Tr BngRespack1K1 3Bin TrBT1K2 100K2 4T inC100nF1T Cm 33pF2 150pF1 C1032 10uF1T Ha 1000uF-25V2 5DIODE cuBR2A1 6LEDD3V-15mA1LED-RED 7TransistorBC1411Transistor thng TIP411Transistor cng sut 8Cng TcCT1Nt n 9Thch AnhCrystal12MHz1 10ICADC08041ADC AT89C521VK 11ENCODERECODER256x/v-5V1 12Cch Ly QuangTLP521_11 13DmCOM-H22 COM-H32 2: Thit k phn mm #include #include sbit bf = P0^7;//Co ban LCD sbit rs = P2^0; sbit rw = P2^1; sbit en = P2^2; sbit rd=P3^5;//Read signal P3.5 sbit wr=P3^6;//Write signal P3.6 sbit intr=P3^7;//Write signal P3.7 sbit pwm = P3^0; N TT NGHIP GVHD: TS.Mai Hong Cng MinhPage 43 Nhm Sinh Vin Thc Hin: Nhm 13 char bien,bien1,bien2,bien3; unsigned long adc_avg,adc,vdat; void LCDint(long); void LCDinit(void);//ham khoi dong LCD void LCDcomm(unsigned char); //Ham gui lenh len LCD void LCDchar(unsigned char); //Ham gui ky tu len LCD void LCDready(void);//Ham khao sat LCD co ban khong void LCDstr(unsigned char[]); //Ham gui chuoi ky tu len LCD void LCDclr();//Ham xoa LCD long temp; unsigned char demx=0; unsigned long dem,dem1; long vong,n,encoder=256;//enconder la so lo tren enconder void delay(unsigned long x) { int t; for(t=0;t=0) c=0; else if(i