NGHIEN cuu-TRAODOI
THI^T Kt TINH TOAN L 6 NUdNG THIT TRUYEN DONG B A N G NANG LU'DNG MAT TR(y\
THE DESIGN AJSID CALCULATION A GRILL MACHINE USING SOLAR CELLS
Nguyen The Luong', Nguyen Van ThSng', Pham Van Tuyin', Vu Hihi Long', Tran Minh Bang', Du'ong Quang Ha^
'Trudng Dai hgc Bach Khoa Ha Npi
^Trudng Dai hpc Khoa hpc va Cong nghe Ha Npi
TOM TAT
Lo nuang thit duac su dung pho bien trong cdc ho gia dinh, nhu cdu sir dung Id nuang ngdy cdng cao, rdt nhieu Id nuang vai nhieu mdu md dd duac dua ra, nguon ndng luang cho Id nuang chti yeu tic than cui vd dien tit luai dien. Hten nay, dien tir ndng luang mat trai dang phdt trien rdt mgnh me, hieu sudt cua pin mat trdi ngdy cao trong khi gid thdnh pin ngdy cdng gidm, vi vgy dien tir ndng luang mat trdi dang ngdy cdng duac ung dung rgng rai. Bdi bdo ndy se nghien cim thiet ke tinh todn Id nuang thit sii dung ndng luang mat trdi de truyen dong. Kit qud tinh todn chi ra rdng, vdi Id nung co kich thuac ddi rong vd cao ldn lugt la 600x400x250mm, cong sudt nuang 5kg thit, cong sudt dgng ca cua Id 25 W, tdc do quay cua Id nuang Id 37,5 vdng/phiit, dia xich co so rdng Z = 14, buac xich p=12,7, chieu ddi ddy xich 1702mm, cdng sudt pin mat trod de duy tri hogt dgng cika Id WOW. Chip vi xu ly PICl 6F887-PU duac lua chgn de thiet ke mgch dieu khien Id nuang.
Tir khoa: Ld nuang; Pin mat trai; Ddng ca; Truyen dgng; Vi xu ly.
ABSTRACT
Grill machine was commonly employed in households, needs of grill machine are increasing in recently years. Many grill machines with new models were showed. Charcoal and electricity are used in grill machine where electricity usually takes from gird electricity. Solar electricity is strong developing; the performance of solar eclectricity is improved while the price down, the applied solar elcetricity in houshold is becoming larger. This paper designs and calculates a grill machine using solar electricity to spin the meat. The results showed that, long-large-high dimension of grill machine was respectively 600x400x2 5 0mm, the power of motor was 25W, the speed of grill machine was 37.5 rpm/min, sprocket-wheel and chain size were 1^=14, p=12.7 and 1702mm respectively. The solar electricity power was 100W.PIC16F887-PU Mircoprocessing chip were selected to design control circuit
Keywords: Grill machine, solar electricity, motor, mircoprocessing chip, spin
ISSN 0866 - 7056
TAP CHi CO KHi VIET NAM, Sl 7 nam 2017
NGHIEN cuu-TRAO D 6 |
1. DAT VAN DE 2. YEU CAU KY THUAT LO N U d N G Trong nhiing nam gan day, cung vdi
su phat trien cua kinh te, nhu cau an udng cua ngudi dan da dugc nang cao, rat nhigu nha hang va quan an da dugc md ra de phuc vu nhu cau ciia ngudi dan. Mpt trong cac mdn an dugc ua thich la thjt nudng, vdi cong nghe ciia Nhat Ban va Han Qudc, ben canh do cung co rat nhilu quan thit nudng cua ngudi Viet vdi cac mdn thit nudng mang huang vi truyen thong Viet nhu: Vit nudng, canudng,...Cac mon thit nudng dan trd thanh mon an phd bign trong cac biia cam cua ngudi Viet. Tren thi tnrdng, CO rat nhieu loai Id nudng thit vdi gia thanh tir vai tram nghin den ca chuc trieu dong de phuc vu nhu can cua ngudi dan [1-3]. Vdi nhung Id nudng nh6 co gia vai tram nghin thudng kieh thudc nhd, loai nay thuimg phai dao thit va quat gio bang tay, ngoai ra loai 16 nay chi cd thg nudng dugc miing thit nh6, thit thudng bi kho. Ddi vdi Ioai 16 nudng co kich thudc Idn, thudng CO lap thgm quat va he thong quay thit bang dien, loai nay co the nudng dugc nhung tang thit ldn, tuy nhien kem theo se cd kich thudc va trpng lupng Idn, rat khd di chuygn, khong phil hgp vdi cac hg gia dinh. Ben canh dd, cae Id nudng nay thudng sii dung dgng ca cap dien true tiep tir nguon dien ludi dan tdi nguy higm do dudng day co the bi hd gay giat dien va khi mat dien thi 16 khong thg quay dugc. Hien nay, dien tir nang lugng mat trdi da dugc iing dung trong rat nhieu ITnh vuc ciia ddi song xa hgi tii nhiing ling dung nhd nhu:
Sac dien thoai, quat mat dgn nhiing ITnh vuc to ldn nhu vii try, xe, tau, may bay dien... [3], Bai bao nay se trinh bay nghign ciru tinh toan thilt ke 16 nudng thit cong suat nhd, su dung dien tir nang lugng mat udi dg dan dpng quay thit va quat gio cho 16.
Lo nudng cd kich thudc nhd ggn co kha nang nudng va quay dugc 5kg thjt vdi 3 xien nudng ciing lite, toe dp quay cua 16 trong khoang 40 vdng/phut. Ld hudng den doi tugng la hg gia dinh vdi so ngudi phuc vu tdi da 15 ngudi. Ld c6 tinh ca dpng cao, tinh thao lap di dang, cd hieu suat nhiet tdt va co gia thanh re.
L6 sir dung nang lugng sach va nang lugng tai tao.
3. NGUYEN LY LAM VIEC CUA LO NU'dNG THIT
1} E
Hinh 1. Nguyen ly ldm viec ctia Id nuang thit Dua theo ygu cau ky thuat d tren, nhom tac gia da lira chgn than ciii va dien tir nang lupng mat trdi de gia nhiet va tao chuygn dpng cho may, dudi day se trinh bay chi tilt nguyen ly lam viec ciia may (hinh I).
Than cui dugc cho vao 16 nudng va gia nhiet dot chay than ciii, dien tii pin mat trdi se dugc truygn den bp dieu khien sac, tai day dien se dugc truyen dgn ddng ca va quat de cung cap dien cho dgng ca va quat, trong trudng hgp Id nudng khdng hoat dpng, bp dilu khien sac se digu khien dg nap dien cho ac quy du phdng trong trudng hgp khdng co nang lupng mat trdi. Khi Id nudng hoat ddng, quat gio se digu khien tdc dp gia nhiet ciia Id, ddng ca dien thong qua bg truygn dpng se quay cac xign thit nudng.
NGHIEN CU'U-TRAO DOI
3. TINH TOAN NHIET L 6 NlfdNG
LLiJ
Hinh 2. Mo hinh tinh todn nhiet cua Id nuang thit Theo kinh nghiem, de nudng 1kg thit can dien tich nudng toi thilu khoang 400 cm^
vd 400 gam than cui, vi vay dg nudng hit 5 kg can dien tich 2.000 cm^ va 2 kg than ciii, de them dien tich du trii cho Id ta chpn dien tich Id nudng khoang 2.400 cm^, trong ygu cau thiet kg Id nudng nhd ggn va co tinh tham my, chieu dai, rdng, cao chgn \kn lugt la 600x400x250mm, sau day se tinh toan nhiet cho Id cd kich thudc nhu trgn. Qua trinh tinh toan dugc thuc hien theo cdng thiic sau [4]:
Q = m.q (1)
Trong do:
Q-Nhiet Iugng toa ra (J).
q-Nang suat tda nhiet ciia nhien lieu (J/kg), nang suat t6a nhiet than cui q =34.10*' J/kg [4].
m-Khdi Iugng ciia than ciii bi dot chay hoan toan (kg), m^2kg.
Thay vao cdng thuc (1) ta cd nhiet lugng toa ra la:
Q=2.34.1O^68.I0^(J)
Lugng nhiet nay tda ra trong thdi gian khoang 2h du dg nudng chin 5kg thjt, tinh trung binh tic dd toa nhiet trong mdt gid la 81,6.10^ (Kcai/h).
Nhiet lugng tda ra bao gom, nhiet dg nudng thiie an theo hudng lgn tren, nhiet toa ra xung quanh va xudng day 16, vi vay phuang trinh can bang nhiet ciia Id co dang nhu sau:
Q - Q , + Q, + Q3+Q4+Qd+Qn (2) Trong do: Q,, Q^, Q3, Q^, Q^ la nhiet Iugng toa ra cac thanh va day Id (hinh 2).
Q^ - Nhiet lugng dimg d l nudng.
Ta cd: Q,, Q^, Q^, Q^, Q^ tinh theo cong thlic truygn nhiet qua vach phang [4].
Q = ?..F.(t,-t,)/5 (3)
Trong do: X, la he sd dan nhiet ciia ldp each nhiet (Kcal/m.°C.h).
5- Chieu day cua ldp each nhiet.
•^1234d' •'^''^" *'^^ ^^^ "^^^ truyen nhigt (m^).
AJ = tj - t^: Do chenh leeh nhiet do giira mat trong va mat ngoai ciia thanh Id ("C), vdi t^ - Nhiet do xung quanh thanh 16 va day 16, tj=40''C, t| - Nhiet do thanh 16, bSng thuc nghiem ta xac djnh dugc, nhiet do thanh 16 va day 16 ian lugt la I lO^C va 650"C.
Vat lieu each nhiet la bong thuy tinh + Xi mang chiu nhigt c6 he sd truygn nhiet la A. = 0,5 (Kcal/m.-C.h).
Chieu day ldp each nhiet dugc chpn bang 10 mm, 6 = 1 0 mm.
Hinh 2, chi ra rang dien tich tda nhiet ciia tbanh Id Q, va Q^, Q^ \k Q^ la nhu nhau, vi vay ta co Q, = Q3, Q^ = Q^
0=
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NGHIEN c u u - T R A O e 6 l
Ap dung cdng thiic 3 ta co:
Nhiet toa ra mat bgn Q, =Q^ = 350(Kcal/h);
Nhiet tda ra mat ben Q^ - Q4 ^ 525 (Kcal/h);
Nhiet tda ra mat day Q^ = 7320 (Kcal/h).
Khi dd ta CO : Q„ = Q - 2Q, - 2Q,-Q^=
72530 (Kcal/h).
Tong lugng nhiet that thoat la:
QrQi+Q2+Q3+Q4+Qd = ^^'^^ (Keai/h).
Phan tram lugng nhiet that thoat la (Q^/Q).100% = 9070/81600.100%-ll,12%.
4. THIET KE TINH TOAN LO NU'CflVG THIT
4.1. Thiet ke lo nudng
Hinh 3. Lo nuang thit sir dung ndng luang mat tr&i:
I) DQng ca; 2) Bdnh xich chit dgng, 3) Bdnh xich bf dQng:
4) Bo cdng xich: 5) So truyin true vit bdnh vit: 6) Jc guy:
7) Qugt; 8) Bdnh xe. 9) Khoi V: !0) Cua cdp gio.
li) Than id, 12) Bdng thuy link + Xi mdng chiu nhiet, } 3) HQP dan gio; 14) Gia da 16,
15) BQ dieu khiin sgc nang lu^mg mat tr&i MPPT;
16) Tdm pin ndng lircmg mgit tr&i. 17)Xiindcm;
18) Xien kep: 19) Ddy xich
Nhu da tinh toan d tren, than Id II c6 kich thudc 600x400x250mm, than dugc phii ldp each nhiet 12 va dugc d^t trgn gia dd 16 14 sao cho kich thudc tong thg cua Id 800 ram (huih 3). Dg thuan tien cho vice di chuyen, 16 nudng dugc l4p them cae banh xe 8, ke va than Id dugc lam ddi sau do lap ghep vdi nhau bSng bu ldng. L6 dupc thigt kg cd thg lap dugc nhieu loai xien nudng nhu xien don 17 va xign kep 18 ciing llic, trgn than Id cd bd tri khdi chir V 9 de dinh vi cac xien nudng (hinh 3). Dien tir pin nang lugng mat Udi 16 thdng qua bd dieu khiln sac 15 se dieu khign dgng co dien mpt ehieu I chay, thong qua bp truyen true vit-banh vit 5, toe dp banh vit trong khoang 30 - 40 vdng/phiit, tir day tdc dp ciia banh vit dugc truygn den banh xich 2, banh xich 2 se an khdp vdi day xich 19 dg dan dgng cac xign quay thjt, dg dam bao toe dp 6n dinh, trgn Id nudng co bd tri thgm bp cang xich 4. Toe dp tda nhiet cua Id dugc dieu khien thdng qua digu khien lugng gid cap cho 16 10 thong qua dieu khien toe do quat 7. Trgn 16 dupc bd tri ac quy 6, ac quy se lam nhiem vu cung c5p dien cho 16 trong tnidng hgp nang lugng mat trdi khong dii, khi nang Iugng mat trdi du ldn, dien tli nang Iugng mat udi se dugc sac ngugc Iai eho ac quy (hinh 3). D I dam bao cho 16 hoat dgng dn dinh va hieu qua, cac tinh toan chi tiet he thong truyen ddng va cdng suat dien eua 16 nudng dupc thg hien d cac ngi dung tiep theo.
4.2. Tinh toan he thing truyen dong 16 nudng 4.2.1. Tinh todn lira chpn dgng cff dien
Khi 16 Iam viec, momen cua dgng ca se truyen tdi true vit, qua hop giam tic true vit - banh vlt se lam giam tdc do ddng ca. D^u ra ciia banh vit dugc noi ddng true vdi dia xich, qua bg truygn xich se din dpng cho xien nudng quay.
Xien nudng dugc gan dia xich cd thdng so Iam viec la: Sd rang Z = 14, budc xich p = 12,7, tir do tinh dugc dudng kmh vdng chia dia xich [5,6]:
NGHIEN cuu-TRAOOOl
P 12.7 d = —^ = jj^ ^ 57 (mm)
sin(-) s i n ( - ) De don gian, ta Iam bg truyen xich vai ti so truyen 1. Nen ta chgn dia xich cd thong sd giong vdi thong s l dta tren xien.
Tir ygu cau toe dp vdng quay w = 40 vdng/phiit va ban kinh dia xich r = 0,0285 m, ta tinh dugc van tdc dai ciia xich:
v=w-r^0,12 (m/s) Cong suat tinh toan:
P =F.v=6 (W)
Cdng suat can thiet ciia ddng ca:
p - ^
Trong dd: n la hieu suat chung cua bg truyen, dugc xac dinh theo cong thiic:
n= %*\
r[^ - Hieu suat bp truyen true vit, chgn so bd Z, = 2 nen n = 0,78.
q - Hieu suat bd truygn xich, chgn T\ - 0,91.
Tir do ta co:
0,78 + 0,91 = 8,46 (W) Dua theo dpng ca tren thj trudng ta chgn dpng ca 1 chigu cdng suat 25W, tdc dp vdng quay 1500 vdng/phiit.
Tir thong sd ciia dpng co va ti sd truyen
Clia bd truyen true vit-banh vit, tinh dugc tic do quay thuc te ciia xign:
4.2.2. Tinh todn bp truyen xich
Cac dTa xich co dudng kinh vdng chia d = 57mm. Do vay, khoang each lap giiia true cua xien va dTa dan ddng la 57mm. Hai xign dugc dat tren 2 thanh V dg dinh vi. Hai dia xich dan dpng dupc lap sao cho true each mat tren ciia Id la 50mm. Do vay, 2 thanh V phai dugc lap sao cho true ciia 2 xien each true ciia dia dan ddng la 57mm (hinh 4).
Dg lap dat de dang tao dp can bang, ta lap true banh xich chii dgng each day 16 80mm va d giiia than 16 (hinh 4).
Hinh 4. Sa do linh todn bg truyen xich Do trong qua trinh boat ddng, dTa xich dan dan se bi mdn nen can lap 1 bg cang xich, Dg can bang vdi phia dpng ca, bp cang xich se dat each true banh xich chii dgng la 180mm.
Chigu dai xich can thiet:
<r
ISSN 0866 - 7056
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NGHIEN CU'U-TRAO D 6 |
7r'(57 + 57)
L f^ 500 + 375 + 180 + 289 + 2 * — » 1702 {mm) Sd m a t x i c h c a n thigt:
C h p n so m a t xich la 136.
4.2.3. Tinh chgn cong sudt pin mat troi
Be cung cap dii luu lugng gio cho qua trinh chay trong Id, can chgn quat gid 12V - IA CO thg thay ddi toe dp. Cu thg khi mdi bat dau, can nhilu oxy cho qua trinh chay nen de quat chay hgt cong suat, sau khi lira da chay, sir dung chiet ap de dieu chinh tdc do quat hoac CO thg tat han quat.
Cdng suat can thigt chay quat la [7]:
P = U.I =12* 1 = 12(W)
Do do, cdng suat dien can thiet de chay he thing gdm cdng suat cung cap cho quat va dgng ca:
p = P + p = 2 5 + 12 = 37 (W) De nap dugc nang lugng tir pin mat troi vao ac quy can phai qua mpt thiet bi dg chuyen ddi vdi hieu suat khoang 80 - 90%. Mat khac, hieu suat hap thu nang lugng mat trdi eua tam pin phu thudc vao hudng chigu nang va do manh ciia anh sang, trong khoang 60 -^ 80%.
Do do, chpn hieu suat chuygn thanh dien sau cimg Clia tam pin la 60%. Vi vay, cong suat can thigt ciia tam pin la:
Py 37
^V^n = 7^= — ^ 6 1 . 6 7 (M/)
Chgn cong suat tam pin la lOOW (cong suat phil hgp vdi tam pin tren thi trudng).
4.2.4. Thiet ke mach dieu khien Id nw&ng tich hop MPPT
c t t
n Y^m -Ti
Hinh 5. Mach diiu khien tich hap MPPT trong Id nuang
NGHIEN CUU - TRAO DOI
Hinh 5, chi ra mach bd dieu khien Id nudng tich hgp MPPT (Maximum Power Point Tracker), bao gom khdi vi xir ly PIC16F887- PU, khoi dieu khien pin mat trdi MPPT, khoi nguon de cung cap nguon 5V va 12V cho mach dieu khign, khoi giao tigp vdi may tinh dg nap dii lieu cho vi xir ly, khoi cong suat dg digu khien dgng ca va quat. Dien ap ra ciia pin mat trdi dugc dua vao chan 2 (RAO) ciia vi xii ly thong qua mach chia ap (sir dung dien trd R l , R2) va bp khueeh dai lap sir dung mach khugch dai thuat toan. D6ng dien cap bdi pin mat trdi se do va bign ddi thanh dien ap dua vao chan 3 (RAI) ciia VI xir ly tir sensor do d6ngACS712 su dung cong nghe cam bien Hall vdi dp nhay khoang lOOmV/A. Viec su dung sensor Hall se lam tang dp chinh xac ciia mach do dong do dupe each ly vdi mach cong suat. Tir do, bp vi xir ly se tinh toan dugc cdng suat cung cap thuc te ciia pm mat trdi dg ap dung thuat toan MPPT. Cimg vdi cac thong tin vg cong suat phat ra tir pin mat trdi, dien ap thuc tg tren ac-quy se dugc do true tiep tir mach chia ap (dien trd R5 va VRI). Dua vao cac thong tm nay, vi xii ly digu khien mach buck-boost ciia bp biln ddi DC/DC bang each digu khien do rpng xung (PWM) dong md MOSFET Ql va Q2 thdng qua 2 chan dieu khien 16 (RCl) va 17 (RC2) cua vi dilu khien va lira chpn che dp boat ddng thich hgp (sir dung nguon tir pin mat Udi hoac chi sir dung nguon dien tir ac- quy) bang rale (chan 8 - REO). Ben canh dd, nhiet dp do dugc cua 16 quay thit nudng se dupc do dac thong qua dien trd nhiet RTI de tir do vi dilu khien dilu chinh tdc dp ciia quat va ca efiu truyln dgng bang tin hieu tir 2 chan 9 (REl) va 10 (RE2). Ngoai ra, mach cung co
cac chirc nang phu khac nhu giao tiep may tinh qua cong RS232 va digu khign 16 quay bang cac niit nhan tren mach.
5. KET LUAN
Bai bao da thigt kg thanh cdng 16 nudng thit va mach dieu khien 16 nudng su dung nang lugng mat trdi. Nghign ciru chi ra rang, viec sir dung bong thuy tinh ket hgp vdi xi mang chju nhiet lam thimh 16 giiip tdn that nhiet d mirc 11,12%. Tinh toan cho thay, cong suat ddng ca va tdc dp Clia 16 lan lugt la 25W va 37,5 vdng/
phut, banh xich c6 sd rang lit 14 rang, chieu dai day xich va so mat xich lan lugt la 1702mm va 136 mat xich, cong suat pin mat trdi 100W.*>
Ngay nhan bai: 12/7/2017 Ngay phan bien: 20/7/2017 Tai lieu tham khao:
[1]. http://bepnuongnanihong.com/
[2]. http://www.themeatguy.jp/app/ja/products/
view/1051.
[3]. https ;//www. cpc. vn/home/Ttuc_Detail.aspx
?pm=ttuc&sj=KHKTND&id-10200#.WM- XM7iQDDc
[4]. Biii Hai, TrSn Thl Son; Ky thuat nhiet, NXB. Khoa hoc va Ky thuat, 2004.
[5]. Trinh Chat, Le Van Uyen; Tinh todn thiit ke he ddn dong ca khi- Tap i,NXB. Giao due, 2006
[6]. Nguyen Trong Hiep; Chi tiit mdy - Tap 2, NXB. Giao due, 2006
[7]. Dang Van Dao, Le Van Doanh, Ky thugt dien, NXB. Giao due, 2009.
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