'\QDPLF9ROWDJH6WDELOLW\(QKDQFHPHQWXVLQJ
0LFURJULG9ROWDJH6WDELOLO]HU
*RODJDQD6DQWRVK
Department of Electrical and Electronics Engineering Pragati Engineering College, Surampalem, Andhra Pradesh, India
,0XUDOL.ULVKQD
Department of Electrical and Electronics Engineering Pragati Engineering College, Surampalem, Andhra Pradesh, India
36DLOHVK%DEX
Department of Electrical and Electronics Engineering Pragati Engineering College, Surampalem, Andhra Pradesh, India
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
.H\ZRUGV±0*96'(*'*'$(,2
,,1752'8&7,21
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
,,02'(/,1*2)0,&52*5,'
,QWKLVSDSHUWKHPRGHOLQJRIWKHPLFURJULGLQFOXGHVWKHPRGHOLQJRIWKH'LHVHO(QJLQH*HQHUDWRUVV\VWHP ORDGV DQG WKH WUDQVPLVVLRQ V\VWHP )ROORZLQJ WKH G\QDPLF PRGHO IRU 'LHVHO (QJLQH *HQHUDWRUV LQFOXGLQJ WKH G\QDPLFDQGDOJHEUDLFHTXDWLRQVLVSUHVHQWHGDQGGLVFXVVHG,QDGGLWLRQWKHQHWZRUNHTXDWLRQVLQFOXGLQJWKHSRZHU IORZHTXDWLRQVDWGLIIHUHQWEXVHVDUHSUHVHQWHG
A. Modeling of Diesel Engine Generator
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
7KHVWDWRUDOJHEUDLFHTXDWLRQVDUHGHULYHGIURPWKHG\QDPLFHTXLYDOHQWFLUFXLWDVVKRZQLQ)LJXUH>@DQGDUHJLYHQ
EHORZLQ
)LJXUH'\QDPLFHTXLYDOHQWFLUFXLWRID6\QFKURQRXV*HQHUDWRU
7KHORDGVDQG'(*6DUHFRQQHFWHGWRWKHGLVWULEXWLRQQHWZRUNZLWKDNQRZQ<PDWUL[LVVKRZQLQ)LJXUH 7KHRYHUDOOPLFURJULGV\VWHPLVPRGHOHGE\ZULWLQJWKHSRZHUIORZVHTXDWLRQVIRUDOO%XVHV>@DVVKRZQEHORZ
)LJXUH'\QDPLFHTXLYDOHQWFLUFXLWZLWKORDGVDQGJHQHUDWRUV
7KHSRZHUIORZHTXDWLRQVIRUORDG%XVHVDUHJLYHQEHORZLQ
7KHDERYHVHWRIGLIIHUHQWLDODQGDOJHEUDLFHTXDWLRQVIURPJLYHVWKHRYHUDOOPRGHORIWKHPLFURJULG ,,,0,&52*5,'92/7$*(67$%,/,=(5
7KH0*96JLYHVDQLQSXWWRWKHH[FLWDWLRQV\VWHPVRUUHDFWLYHSRZHUORRSVRI'*VZKLFKDFWVWRNLFNLQ PRUHUHDFWLYHSRZHULQWRWKHPLFURJULGWRSUHYHQWDQ\YROWDJHFROODSVH$Q\VPDOOLQFUHDVHLQUHDFWLYHORDGFDQEH PHWE\WKH'*VDYRLGLQJWKHXVHRIH[SHQVLYHG\QDPLFUHDFWLYHVRXUFHVVXFKDV67$7&2069&RUFDSDFLWRU EDQNV7KHPLFURJULGYROWDJHVWDELOL]HUPRGHODQGLWVVLPSOLILHGYHUVLRQDUHVKRZQLQ)LJXUHDQG)LJXUH>@
)LJXUH0LFURJULG9ROWDJH6WDELOL]HU
)LJXUH6LPSOLILHG0RGHORI0LFURJULG9ROWDJH6WDELOL]HU
7KH LQSXW WR WKH 0*96 LV D PHDVXUH RI WKH YROWDJH GHILFLHQF\ RI WKH PLFURJULG 7KH SHU XQLW YROWDJH GHYDWLRQǻ9HUU LEHWZHHQWKHGHVLUHGYROWDJH9GHV LDQGWKHG\QDPLFYROWDJH9GHVLLVFDOFXODWHGIRUDOOWKHORDG %XVHVL «ODVVKRZQEHORZLQ
)LJXUH([FLWDWLRQV\VWHPRIDJHQHUDWRU
90*96 UHSUHVHQWV WKH WRWDO 0*96 FRUUHFWLQJ VLJQDO ZKLFKLV GLYLGHG EHWZHHQ WKH '*V GHSHQGLQJ RQ WKH JHQHUDWLRQUHDFWLYHUHVHUYHSUR[LPLW\WRLQGXFWLYHORDGVHWF7KHZHLJKWLQJIDFWRUVIRUWKHJHQHUDWRU%XVHVWR JDUHȕȕ««ȕQ90*96LLVWKHLQSXWWRWKHLWKJHQHUDWRU¶VH[FLWDWLRQV\VWHPDVVKRZQLQ)LJXUH
,96,08/$7,215(68/76
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
A. Voltage Stability Analysis of the Microgrid System in Grid-Connected Mode
,QWKHJULGFRQQHFWHGPRGHWKHPLFURJULGWHVWV\VWHPLVFRQQHFWHGWRWKHPDLQJULG7KHORDGDW%XVLV WKHODUJHVWORDGLQWKHPLFURJULG6RWKHORDG%XVZHLJKLQJIDFWRULVKLJKHVWIRU%XV7KH0*96GDWDWDEOH FRQVLVWLQJRIORDG%XVZHLJKWLQJIDFWRUVJHQHUDWRU%XVZHLJKLQJIDFWRUVDQG0*96FRQWUROSDUDPHWHUVDUHJLYHQDV IROORZV
7DEOH/RDG%XV:HLJKLQJ)DFWRUV
Į Į Į Į Į Į Į
7DEOH:HLJKLQJ)DFWRUVIRU*HQHUDWRU%XVHV
ȕ ȕ ȕ
7DEOH0*96&RQWURO3DUDPHWHUV *DLQFRQVWDQWN 7 7
$WKUHHSKDVHVKRUWFLUFXLWIDXOWLVDSSOLHGDW%XV7KHGLVWXUEDQFHVWDUWVDWRIWKHWRWDOWLPHLHVHFDQG HQGV DIWHU VHFV 7KH UHVXOWV VKRZ WKDW WKH ORDGEXVYROWDJHVLPSURYH E\ PRUH WKDQ LQ WKHSUHVHQFHRID 0*96DVVKRZQLQ)LJXUHDW%XV
)LJXUH7KUHHSKDVHIDXOW&RPSDULVRQRIYROWDJHD%XVZLWKDQGZLWKRXW0*96LQJULGFRQQHFWHGPRGH
7DEOH&RPSDULVRQVRIYROWDJHV:LWKDQG:LWKRXW0*96DW1RUPDO&RQGLWLRQZLWKRXW)DXOWDQGZLWKSKDVH6KRUW&LUFXLW)DXOW
,Q RWKHU FDVHWKH ORDG DW %XV KDVEHHQ LQFUHDVHGE\ 7KH GLVWXUEDQFH VWDUWV DW RI WKH WRWDO WLPH LH VHFDQGHQGVDIWHUVHFRQGV7KHUHVXOWVVKRZWKDWWKHYROWDJHDW%XVLPSURYHVLQWKHSUHVHQFHRID0*96 DVVKRZQLQ)LJXUH
%XV9ROWDJHV
1RUPDOFRQGLWLRQZLWKRXW)DXOW :LWKSKDVHVKRUWFLUFXLW)DXOW
:LWKRXW0*96 :LWK0*96 :LWKRXW0*96 :LWK0*96
9
9
9
9
)LJXUH/RDG6ZLWFKLQJ&RPSDULVRQRIYROWDJHRI%XVZLWKDQGZLWKRXW0*96IRULQFUHDVHLQORDGDW%XVLQJULGFRQQHFWHGPRGH
7DEOH&RPSDULVRQVRIYROWDJHV:LWKDQG:LWKRXW0*96ZLWK/RDG,QFUHPHQW
%XV9ROWDJHV :LWKRXW:LWKH[WUDORDG
0*96 :LWK0*96
9
9
9
9
9
B. Voltage Stability Analysis of the Microgrid System during Islanding Operation
'XULQJWKHLVODQGLQJRSHUDWLRQWKHOLQHEHWZHHQ%XVDQG%XVLVUHPRYHGHIIHFWLYHO\GLVFRQQHFWLQJWKH PLFURJULGIURPWKHPDLQJULG1RZWKHWRWDOORDGLVVXSSRUWHGE\'*VDW%XVHVDQG7KHORDGSDUDPHWHUV UHPDLQXQFKDQJHGEXWWKHSRZHUJHQHUDWLRQDWWKHJHQHUDWRUVFKDQJHVGXULQJWKHG\QDPLFHYHQWV7KHGLVWXUEDQFH VWDUWVDWRIWKHWRWDOWLPHLHVHFDQGHQGVDIWHUVHFRQGV7KHUHVXOWVVKRZWKDWWKHYROWDJHDW%XV LPSURYHVE\PRUHWKDQLQWKHSUHVHQFHRID0*96DVVKRZQLQ)LJXUH
7LPHVHF
%
XV
YR
OWD
JH
SX
:LWKRXW0*96 :LWK0*96
)LJXUH,VODQGLQJRSHUDWLRQ&RPSDULVRQRIYROWDJHVDEXVZLWKDQGZLWKRXW0*96
C. Voltage Stability Analysis of the Microgrid System in Islanded Mode
7LPHVHF %X VYR OWDJH SX :LWKRXW0*96 :LWK0*96
Figure 10. Three phase fault: Comparison of voltage a bus 19 with and without MGVS in islanded mode
D. Voltage Comparison of Buses with and without MGVS:
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
5()(5(1&(6
>@ 08=DKQG&RQWURO6WUDWHJLHVIRU/RDG)ROORZLQJ8QEDODQFHG0LFUR*ULGV,VODQGHG2SHUDWLRQ)DFXOWp6FLHQFHVHW7HFKQLTXHVGH O,QJpQLHXU/DXVDQQH067KHVLV
>@ $.XULWDDQG76DNXUDL7KHSRZHUV\VWHPIDLOXUHRQ-XO\LQ7RN\RLQProceedings of the 27th IEEEConference on Decision
and Control$XVWLQSS
>@ 86&DQDGDSRZHUV\VWHPRXWDJHWDVNIRUFH)LQDOUHSRUWRQWKHDXJXVW%ODFNRXWLQWKH8QLWHG6WDWHVDQG&DQDGD&DXVHVDQG 5HFRPPHQGDWLRQV1DXWUDOUHVRXUFHV&DQDGDDQG86GHSDUWPHQWRIHQHUJ\3DJHV5HSRUW
>@ /5REHUWU$$NKLO0&KULV6-RKQ'-HII*5RVV$66DNLV<5REHUWDQG(-RH,QWHJUDWLRQRI'LVWULEXWHG(QHUJ\5HVRXUFHV 7KH&(5760LFUR*ULG&RQFHSW86'HSDUWPHQWRI(QHUJ\:KLWH3DSHU/%1/
>@ 3:6DXHUDQG0$3DLPower System Dynamics and StabilityQGHG&KDPSDLJQ86$,OOLQRLV6WLSHV3XEOLVKLQJ
>@ 3/-HIIUH\0RGHOLQJRI'\QDPLF/RDGVIRU9ROWDJH6WDELOLW\6WXGLHV7HQQHVVHH7HFKQRORJLFDO8QLYHUVLW\&RRNHYLOOH067KHVLV
