THIET KE THIET Bl THI NGHIEM TRONG DAY HOC
"DONG CO KHONG DONG BO 3 PHA, VAT LJ LOlP 12
TS. Nguyin Anh ThU^n - Trudng BHSPHA NQ, Nguyen Th! Thu Trang - Tnr&ng THPT Budn Ma Thupi SUMMARY
This paper presents the research design, manufacturing and laboratory equipment for use in teaciiing
"asynchronous motors 3 phase" in 12 school physics program High School.
Keywords: Engines three-phase asynchronous.
Ngdy nhgn bdi: 19/10/2015; Ngdy duyft ddng: 20/10/2015.
V§t li d trudng pho thdng chft ylu Id vgt li thuc nghifm, mOt trong nhftng khau quan Irpng cfia qua Irinh dli mdi phuong phap day hpc bO mdn vgt ii la phdi tdng cudng cdc hogt dOng thye nghifm cfia hpc sinh (HS) Irong qud trinh hpc l§p. Vi v§y, vifc sir dyng TBTN trong dgy hpc dl tgo dilu kifn de hpc sinh tilp c$n vdi con dudng nghiln cftu khoa hoc, giup HS hieu sdu sdc vd v§n dyng dupc cac kiln thuc v^t Ii Id rat can thilt. Thdng qua vifc thiet ke phirang dn thi n^ifra, tien hdnh cdc thi nghifra..., HS dupc rin luyfn kT ndng, kl xdo, gido dye ting hgp, hlnh thdnh tu duy sdng tgo vd tinh than ldm vifc tap the.
1. Sy cdn thiet phai thiet kl, chi tgo TBTN DOng CO khdng ding bO 3 pha Id logi rady difn (chuyin difn ndng cfia ddng difn xoay chieu 3 pha Ihdnh CO ndng quay ciia roto) dupc sfi dyng pho bien trong kl thugt truyen dOng difn do cd cdc uu diem la:
don gidn vl kit cdu, gpn nh?, dl che tgo, de sft dyng vd hifu sudt cao.
Bk cd thl dgy hpc vl "DOng eo khdng dong bp 3 pha" - vgt It 12 THPT nhdm phdt \»xy linh tich eye, phat trien ndng lyc sdng Igo cua HS thi can phdi cd TBTN dk tien hdnh cdc thi nghifm kiem n^if m cdc d$c diem cfia tft Irudng quay vd sy quay khdng ddng bg.
Hifn nay, trong danh mye TBTN tli thilu d tnrdng THPT khdng cd TBTN vl dgng co khong ding bO 3 pha. MOt so tdc gid dS dk cgp nghiln cuu TBTN ve dOng co khdng dong bg 3 pha (Ddo Vift Phuong, Khdmsoulin Chdnthavong...). Tuy nhien, cdc TBTN hifn cd ehi sft dyng dfing nguon di?n 3 pha tft mdy bien tdn cdng nghifp ho$c mdy phdt difn 3 pha chuySn dyng, dOng ca khdng ding bp 3 pha co kit cdu khd phftc tgp.
2. Cau tgo vd nguyen tic faogt dpng ciia TBTN TBTN do chung tdi xay dyng gim ede chi tiet nhu hinh 1.
H • TAP CHi THlfrSIGlAO pgc-sd 123-11/2015
Hinh I. TBTN ve dgng ca khong dong bg bapha a) Mgch phdt difn xoay chieu ba pha: Mach phat difn xoay chieu ba pha cd chuc ndng bien difn ap xoay chieu mpt pha thanh ngudn difn dp xoay chieu ba pha cung cap cho dgng co.
Mach phat dien xoay chieu ba pha sft dung ngudn diln xoay chieu 1 pha (220V; 5,5A; 50/60Hz) dupc chinh luu va Igc thanh difn ap mpt chieu (12V;
2A) nhd bp chinh luu (6), Difn ap mpt chilu naj- dupc bien doi thanh dien ap xoay chieu 3 pha doi xung (3V; 0,3A; 37Hz; mdc hinh sao) nhd mach nghjch luu (2).
Hmh 2 Dgng song di^n ap ra i.na mgth phal di?n xoay chieu 3 pha Irin dao dong ki di^n tir: a) pha I
va pha 2, b) pha 2 va pha 3 b) Bpng Cff khong dong bg ba pha - Stato (1) gom 3 cupn day gidng nhau bd tri Ifch nhau 120''tren mpt vdng tron; 6 dau day cua ba
cN ctru & UNG DUNG
cuOn day dugc ndi hinh sao.
- Rd to (4) id khung day gdn tren tryc quay thing dftng.
c) Cdc linh ki^n khdc: Kim nam cham gdn trln tryc quay thdng dftng (5), cuOn day (3).
3. Cdc tbi nghifm cd the tien hanh vdi TBTN a) TN 1: Tit trudng tgo ra bdi dbng dif n 3 pha Id tir trudng quay
- ,Myc dieh TN: Khdo sat tft trudng tgo ra bdi ddng difn 3 pha la tft trudng quay.
- B l tri vd tiln hdnh TN:
Hinh 4: Dgng song difn dp tren ciign ddy dgt trong tir trudng quay
phdng tgo bdl 3 tryc cfia cac cuOn day stato.
- Bd tri va tiln hanh TN: TN dugc bo Iri vd tiln hdnh nhu TNI. Quan sdt chuyen dOng cua kim nam cham trong trudng hpp_ thft nhdt: tryc quay cua kim nam chdm dupc d|t thdng dftng vd trudng hyp thft hai' tryc quay ciia kim nam chdm dupc ddt ndm ngang.
- Ket qud TN: Trudng hpp thfi nhat: kim nam chdm quay deu, Trudng hpp thft hai: kim nam eham dftng yln. Chimg td, tft trudng quay cd_phuong ndm Hmh 3: Bd tri thi nghifm khdo sdt lit trudng
ddng ba pha tgo ra la lir irudng quay
D^t kim nam ehdm _^3n tren tryc q^uay thjng trong m^t phdng^song song vdi m?it phdng tgo"bdi 3 .,,A n.„„*„*„ v^* f„*„„ _ „* . tryc cfia cdc cupn day Stato,
dftng vdo gifta stato. Ket ndi stato vdi mgch phat difn xoay chiiu ba pha. Bat cdng tdc ngudn difn. Quan sat chuyin dOng cua kim nam cham.
- Kit qud TN: Kim nam cham quay, chftng td tft Irudng tgo ra bdi ddng difn 3 pha Id tft trudng quay.
b) TN2: T^ trirdng quay cd bien dg khdng dii, chu ki quay khdng doi vd bdng chu ki cda ddng difn
- Myc dich TN: Khdo sdt bien dp vd chu ki quay cfia tft trudng qua);.
- Bd tri vd tiln hdnh TN: TN dupc bd tri nhu
d) TN 4: Tic dp gdc cua rdto nhd htm tic dp gdc cua tir trudng quay
- Mye dfch TN: Chftng td tic dO gdc cua rdto nhd hon toe dp gdc cfia tft trudng quay.
- Bd Iri vd liln hdnh TN: TN dupc bo tri nhu TNI nhung thay kim nam cham bdng rdto Id khung ddy (4) dupc d$t sao cho tryc quay cfia khung ddy cd phuang thdng dftng vd di qua tdm cfta stato (Hinh 5). Cdp difn cho ede cuOn ddy stato. Quan sdt chuyen dgng cfia
• ^ „ " ? Z T .-• l i ' - ^- A> kh™g '•ay. >'^ *!•* "^hu ki quay cua khung dSy nha
? " "iS;^*. '' • . T ^''^n^^ ™?" ^^ <'? ISng h6 b t a day vi suy ra t& dp goc cOa Aung day.
dirpc d$t d tdm cua stato va noi 2 ddu cuOn ddy vdi dao dOng kf difn tft. Bgt cdng tdc nguin difn. Quan sdt dgng dd thj difn dp trln cuOn ddy trln mdn hinh, dao dOng kl difn tft, xac djnh biln dO vd tdn sd cfia difn dp trln cudn day, rfit ra kit l u ^ vl biln dO vd chu ki quay eua tft trudng quay.
- Ket qua TN: Do thj difn ap trln mdn hinh dao ddng ki Id mOt dudng hinh sin ed biln dp khdng ddi vd chu kl bang ddng difn (Hinh 4). Chung td tft trudng quay cd biln dd khdng dli, ehu ki quay khdng doi vd bang ehu ki cfia ddng difn.
c) TN3: Tittrudng quay cd phuang ndm trong m^t phdng song song vdi mpt phdng tgo bdi 3 trgc cua cdc cupn ddy stato
- Myc dich TN: Khdo sat tft trudng quay cd phuong ndm trong m$l phdng song song vdi mdt
So sdnh Ide dO gdc cua khung ddy vdi toe dO gdc cfia .tu trudng (bdng tdn sd gdc ciia ddng difn).
Hinh 5: Bo tri thi nghifm chung to loc dp gdc cua rdto nho han tdc dp goc cua tir trudng quay
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