Thực thi các bộ điều khiển để xác định điểm công suất cực đại của bảng pin mặt trời sử dụng LabVIEW

Hinh 6 la giao dien nguoi sir dung duac xay dung bang phan mem LabVIEW cho phuong phap P&O va cho phuong phap dua tren logic ma.. Giao dien bao gom cac phan tit do luong ao Virtual Instr

2 ' la ham trl &cn\ vi (ham tre sau mot chu ky lay

mau),

AD( la bi^n thien ciia khoang dan ciia van FET

trong mot chu ky dong cat tai thai diem lay mau

thii k

Hinh 3 So do kh6i bp dieu khien logic ma dung de

mot chu ky dong cat

Khoi m o hoa (Fuzzification) lam nhiem vy

chuyen cac dau vao (ê va dệ) va ra ( A D , ) a

dang gia tri ro thanh cac ham lien thugc co dang

hinh tam giac va hinh thang nhir hinh.4 Thong

thuong, trong thuc te cac ham lien thupc hinh

thang va tam giac dirpc chpn vai ly do cac ham

lien thupc dang nay d§ thuc thi va lam don gian

hoa dang ke qua trinh suy luan mir

Dpng CO suy lu£in (Inference Engine) bao gom 25

quy tac quan he giija 2 dau vao (ê va dệ) va

dau ra (AD,,) duac trinh bay nhir tren bang Ị

Bang Ị Bang cac quy tJc

PB

PS

NS

dẹ

NB

NS

NS

NB

NB

NS

PS

ZZ

NS

NB

ZZ

PS

ZZ

NS

NS

PS

PB

PS

PS

ZZ

NS

PB

PB

PS

ZZ

Trong bang, 1, y nghTa ciia cac chii viet tat tieng

Anh nhu sau:

NB: Negative Big (Am nhilu)

NS, Negative Small (Am it)

ZZ: Zero (Khong am va khong duong)

PS: Positive Small (DuoTig it)

PB: Positive Big (Ducmg nhi6u)

Tai mot thai diem nhat dinh, theo bang, 1 ta co

mot so cac quy t5c mo duac trinh bay nhu sau:

NEU e, la PB VA de, la NB THI AD^ la ZZ

NEU e, la PS VA dê la NB THI AD, la NS

NEU e, la ZZ VA de, l a N B T H I AD, l a N S

NEU e, la NS VA de, la NB Tffl AD, la NB

NEU e, la NB VA de, la NB THI AD, la NB

Cuoi cimg cac tap m a dau ra sg dupe lam ro hoa bang phuong phap trong tam (Centre of Area/COA) nhir sau:

I/'('(0)"(' I/'(-(0) (1)

T r o n g p h u o n g trinh (1) ta c o :

xii) la gia trj thii / ciia khoang bien thifin ciia

h a m lien thupc d a u ra A D , , / i ( x ( / ) ) l a gia trj h a m Hen t h u o c ciia b i l n AD,

l i n g v o i x{i),

•^coA '^ S'^ tti ciia bien thien dau ra AD, sau khi

l a m ro hoạ

!, mm ,0 04 -0.02 0 0.02 0.04 e, max

I -SO 40 0 40 80 de,mxi

(b)

MF

NB NS ZZ PS PB

AD, min 0.04 -0.02 0.02 0,04 AD, max

(c)

Hinh 4 Cac ham lien thupc: (a) Cac ham hen thupc

ciia bien e,, (b) Cac ham lien thupc ciia bien t/e,, (c)

Cac ham Hen thupc cua bien ADk

3 Tbirc ngtiiSm

He th6ng nap kc quy su dung nang lirpTig mat

trcri duac trinh bay nhu tren hinh 5, bao gom:

1- Mot bp thu thap dQ heu 14 bit NI USB-6009 ciia

hang (National Instruments/NI) [8] vdi 2 dau vao

pin mat troi, 1 dau ra tucmg tir dtia den chan dau

vao tuong tir ciia vi dieu khien dsPIC

2- Mach dpng luc: Mach nang ap tir mot chieu sang

mpt chieu (Boost DC/DC Converter) co cac

thong so nhir sau:

- Cupn cam L = 50mH

- T u d i e n C = lmF

- Khoa chuyen mach FET

- Diot chuyen mach D

3- Bang pin mat troi Model SL120CE-24M [9]

4- Mot laptop cai phan LabVIEW dung de do luong

va dieu khien

5- Tai la 5c quy 24V dupe noi vai dau ra ciia mach

nang ap

Mach dieu khien qua trinh dong cat cua khoa

FET sii dung vi dieu khien Microchip

dsPlC33fjl2mc202 vai dau vao la tin hieu tucmg tir

thay doi tir 0 den 3,3V va dau ra la tin hieu diSu biSn

dp rpng xung (Pulse Width Modulation/PWM) tan so

50kHz

Hinh 5 He thong thuc nghiem nap ac quy sii dung

nSng luong mat troi vai MPPT

Toan bo thuat toan dieu khien dupe viet bang ngon ngir C, Phan mem Pelles C [10] dupe su dyng

de bien dich ma ngu6n C ra cac file a dinh dang thu

file DLL sau do se duac gpi ra trong moi tnrang LabVIEW Hinh 6 la giao dien nguoi sir dung duac xay dung bang phan mem LabVIEW cho phuong phap P&O va cho phuong phap dua tren logic ma

Giao dien bao gom cac phan tit do luong ao (Virtual InstrumentsWI) dung de hien thi dien ap cua bang pin mat trai, dong dien cua bang pin mat trai va cong suat ciia bang pin mat troi, Ben canh do, giao dien con hien ihi cac thong so sau:

dD; bien thien khoang dan cua khoa FET trong mpt chu ky dong cat

D k _ l : thoi gian dan trong mot chu ky dong cat

cua van FET tai thai diem lay mau thii k-\

Dk: thai gian dan trong mpt chu ky dong cat ciia

van FET tai thai diem lay mSu thii k

Tin hieu dieu khien (control signal) dua den dau vao analog cua vi dieu khien dsPIC

Do thi bien thien theo thai gian ciia cong su^t Edn nhat bang pin mat troi

Cac gia tri dien ap, dong dien va cong suat dupe liru lai o dang file "txt" de dupe ve lai su dung phan mem Matiab Hinh,7 la thay doi ciia cong suat Ion nhat cua bang pin mat troi iheo thai gian

.^"-j*.!

\-Hinh 6 Giao dien nguai sir dung xay dung I

p h k mSm LabVIEW cho MPPT

20 25 ' " " " I ' l Tim8[s)

(a) Phuang phap P&O (b) phuong phap dua tren logic mo

Hinh 7 Thay doi cong suat lan nhat ciia bang pm mat trai theo thoi gian

5 10 15 20 25 30 35 40 15 £0

•nmels)

(b) Phuang phap dua tren logic met

Hinh 8 Thay doi ciia dien ap ra cila bang pin mat trai theo th6i gian

Fki££y l o ^ method

(a) Phuang phap P&O (b) Phuong phap dua tren logic mo

Hinh 9 Thay doi cua dong dien ra ciia bang pin mlit trai theo thoi gian

Theo hinh 7 ta thay chat lupng dong ciia h^:

thoi gian qua d6 va dp qua dieu chinh cua

phuang phap logic m a nho hen phuang phap P&O

Cu the de dat duac cong suat lan nhat phuang phap

P&O mat gan 10 giay trong khi phuong phap dua tren

logic ma chi mat 5 giay de dat duac cong suat lan

nhat Chat lupng tTnh ciia he: phuang phap dua tren

logic ma CO sai so xac lap nho hon phuong phap

P&O

Hinh 8 va hinh 9 lan lucrt la thay 361 cua dien ap

va dong dien dau ra ciia bang pin mat trai img vai

cong suat Ian nhat theo thoi gian, Phuong phap dua

tren logic m a co tan so va bien dp ciia dien ap va

f Ket luan

Bai bao da tong hop cac buoc thuc thi ciia hai

phuang phap diing de van hanh he thSng nap ic quy

su dung nang lupng mat troi img vai di6m lam viSc

Phuong phap P&O va phuong phap dua tren logic

ma, Cac phirang_ phap nay khong doi hoi phai sii

dung cac cam bien moi truong dk do dp birc xa va

nhiet dp tren be mat ciia bang pin mat triri Phan mem LabVIEW duac sir dyng de do luong va dieu khien cac thong so cua he thong Phuong phap dua tren logic m o CO nhieu uu diem so voi phuong phap P&O Dieu nay cho thay sir dung phuong phap logic mo sg dupe ling dung nhieu hon cho he nang lupng mat troi, nhat la voi cac he cong suat Ion Day se la cac budc nghien cim tiep theo cua nhom tac gia

Tai lieu tham khao

[1] S Bai and B, C, Babu, "Comparative study between P&O and Current Compensation method for MPPT of

PV energy system," Conference on Engineering and Systems (SCES) 2012 Students, (2012) I - 6,

[2] R, Ramaprabha, B L, Mathur, and M Sharanya, "Solar array modeling and simulation of MPPT using neural

network," 2009 International Conference on Control, Automation, Communication and Energy Conservation,

(2009) 1-5

[3] S Prenmideepreechacham and N Patanapirom, "Solar-array modelling and maximum power point tracking

using neural networks," Power Tech Conference Proceedings 2003 IEEE Bologna, vol 2,2003

[4] B K Bose, "Intelligent control and estimation in power

electronics and drives," IEEE 2 International

Conference of Electric Machines and Drives, 1997

[5] F H Martinez S., "Fuzzy logic conUoller for boost

converter with active power factor conection," 7th

Internanonal Conference on Power Electronics, (2007)

936-940

[6] M G Simoes, "Fuzzy Logic Based Intelligent Control

of a Variable Speed Cage Machine Wind Generation

System," IEEE Transactions on Power Electronics, vol

12,(1997)87-95

[7] T Gupta, "Implementation of a Fuzzy Controller for

DC-DC Converters Using an Inexpensive 8-b

Microcontroller," IEEE Transactions on Industrial

Electronics, vol, 44, (1997) 661 - 669

[8] http,//sine.ni,com/mps/cds/view/p/lang/en/nid/20l987

[9] http-//nbkxsolar.en

made-in-ch i n a, CO m/p

roductA'bunvhlYbtiF/China-Mono-Solar-PaneM 20W-SL120CE-24M-,htnil

[10] http://wv/w, smorgasbordet.com/pel I esc/