VT' #J ; 8-AQ M L ' DEE? 5 P

D'& iue.3 &+ G<= & K ^ E /D&/ @8 39 3 ; <= ;5 N?4@ J 76 VT' #J ; 8-AQ M ' DEE? 5 P 3 J5 @\ -Q 5 @A,% Y $+" a ; ;E b.e ) EQ / G A> - &/ J hoseinpour.majid@gmail.com ; ;E b.e ) EQ / G A> - Y!" D" mohamadian@modares.ac.ir 3 ; ;E b.e ) EQ / G A> - & (39/9/ :H9 [i ge 39//3 :H9.+ ge) yazdian@modares.ac.ir &+ D&/ [ D'& @ ^ K+ E K G<= H9? :D8 H9?.C @8 &H 3 ;3 < H&/ 9<@ E &4 K E D&/.3.. < 9<@ E /D&/ D'& @ c&4 d G<= K ;8 DN@.3 K E ;E c49e D&/ c&4.. @8 &H 3 9<@ 4K-E /D&/ ;3 & D'& D'& iue E c&4. KJ 3 `Q &+ D&/ 9<@ K o&./? E &H K ^ E? Y> ;E c49e. ; c&4 d G<= KJ `Q &+ D&/ E K K ^ E :Dc5-E =- D'& > ; iue s K \@7 >,B G&GH AJE ;+K,+ 3E qe E d G<=? / &H A& = D'&?. GE ;3 E D& E.4 & F ; H ^ E.iC 9&4? re E.4 ^ E..[] = :^ K D'& ( HE K & A( / ( HE ;3 HE = KGE D'& K+. 49 ( Hp. C<3 <~. ( HE ;3 D9& K K+ E 3 &- <~ E 4E ;K K \ K ^ K+ E / ; ^ K+ E &- <~ E 4E K+ E >. E 4E K+ E.4 c&4 </ ; CK.<>. H J3.<> ;3 Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

77 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J.4 c&4 3 H 'E. 3 CI 4 \ K / ^.. 9 / ^ E J ;K E :3 G &/ _ 'E E J ;K K+ E G.[3] [] ' E 4E K+ E ^ E </ 8. ( :^ / ~ me HE) \@7 > ~ c ;3 3. 3 dc FH J ;K? &H c49e 3? K+ &H E33=?^ qre K C<3. J ;K &H v3= = (D'& ;3 G D&/ &H / D'& /D&/. b4@ O K43 D&/ : K 3 J ;K E E ;I ( HE ;3 = 3?.. G? <.3 [4] `K&4 cj@ Du K X( K ;K wb& E &H v3=?. dc FH &H D'E := = GH@ dc FH &H ~/@ &G^/ K+ &H F J ;K ^ E.C 5 & ( 5 E ^ E.3? K / dc FH &H ZN E m &H F ^ E = (EMC) 48u &GH CK A7G \ K &H.[5] J ;K ^ E.4 &H d Z< K & ;E /. E7G ^ E? K me 4 K t `/+ ;3 &H / ^ E / ; ^ E 6? 49.[6] @ ;O ~ c 4 J ;K E / H@. & // \@7 > ~ c ;3 (NB? ;E.[] & // 5^ m xn t ;E m& ;E / E KK K.&+C > 3E 4 A> c&4 @8 &H s E K DNE & ) 'E 5E A>,+ ;E.+y,+ ; b& ;,+ ;8.<> ;4G A E? ;3 c49e \ &+C \ K DNE &4 / <4 /P X ; <&B H&/ [. K @ 'E ue i X' (E.+y ; droop ) &+ [ b D 6. c49e </ 6 E? le 6 \ K / &+C A A> G c/@ E Q ω P./ &+ NB K &+ D&/ :. c4 le = /. (method X' Et ;8.<> [? & <5 CK A=78 K +( H&/ [? GJO K...>? 5HN E 3 `Q K )&4 / ic g \ ' / H@. J & i </ c4> ^ ;E / \5H c49e [ : 6. `/+ &H ; ;E c49e (3C: Circular Chain Control) JK 9<@ D&/ (Master-Slave) -<( D&/ / D&/ : c49e.[7] m& ;3 c49e [ ;3 c49e [.C c49e D'+ ;E c49e D'+ ;3 c49e <( C E D'+ c49e [ / l K [? / ^. (@ d 3 &H ;tc {5( ;3 c49e NB D'+ ;E c49e [. [K = D&/ 9<@ ;3 A=78 K s &4 8E 8E l K &?. C & <5 /D&/ &/ &/ ;E A=78 D'+ Hp ;^ 3?. Cm& m G F D)? K /./ F? :J & [? G ;E c49e [ qe &/ &/ ;E 5 G [?.&4 &+ [ & D&/ FGE ) @. G ^ iue [ Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 78 ;E {5( c49e 8E l `Q ;KE :=.4@ &H ;tc ;E c49e 5HN E7G D&/ [.[8]. e d'? s+ <&B [ '& A995E / / G g G? <(+ / xn. K E D&/ wi3 [ K ^ A7G 3 &+.K 8E l K & ;G E /. ;3 D'E := K;3 <&B [ ;/E K+ E KK s3 w> E K &.. & J ;K ^ K+ E K F K+ E K O [].. [9] E &H.~ HE Hp (SRF)-PI H)& -E / D&/ ; HE ;3 K43.. E 3 &H.~ HE (SRF)-PI /D&/ sje &/ ;E K `/+ &+ [ F [4].. [3] D < [] [] K D < ;E <( Hp E c D&/ 7= /. K+ D& (Q-V) &/ ;E K &H.+ (P-f) -.H? E E c (Q-H) G. K G Q O-.H &+ 5 F K & &/ &/.~ HE ;3 HE K &/ ;E b &+ [ F [5]./ nb <5 G G / Q O. &H d4@ &/ ;E `/+ d4@ &/ ;E D& &+ sje E /. m &H [ F [7].. - D&/ [ &- <~ E 4E N& K+ UPS KK [6].. D'& @ J ;K ^ K+ E K K &+ KK C :J / t / ) K+ E KK K :J A995E @ ^ K+ E KK Y95E? K X :J ;/E ^ K+ E. E.+y m D'& H /? ƒ+ H9? :/ d' E KK K [ 3E ^ K E D&/ &+ D&/ [ K 4 8E l K & c K E 3E > <(+ /D&/ ;3 < 9<@ E /D&/ ^ K+ E d K G<=.3.. &.. @8 H9? &H 3 9<@ 4K-E ; H5 5- :. K Y <5E m<&b ;E. ; N& E KGE D' () G S = P + jq () :K E= 99@ ;E / EV P = sinφ X EV cosφ V Q = X ( 3) Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

79 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J N& E KGE D' : G E K G<= D' : G `Q dh < Hp H t'. ; & N& < 3 `Q E () G ƒ+? &H. &+C \ < A( E 3 `Q E 3 &<+ `&/ l,b?.[8]. &+C \ <- A( E 3 `Q At9. &+ Hp b A> G Z<&B E? c49e /. &+C A> c&4 E K &+ D&/ : K G<= :?.C A( K E / D&/ φ K+ K ue 99@ ;E D&/ \.. qp.. \+( E 3 `Q.4> K E K.3 ( E Q ) &/ ;E d4@ &H (ω P ) &/ ;E d4@ `/+ E &/ ;E. nb (3) () / ).. & E Q &/ ;E E &H K (@ ω K `/+ :[8] Z'E K Y &+ m ((3) G Y ) ω = ω mp E = E nq ( 4) (5)? 5HN &4?.,/ &H c\e.> GH@ ;E c49e G<= J &+ dm,+.i A( &? E Q ω P &+ ANB :3 G `/+ &+ D&/ /. D At9 &H c\e c49e Y> D&/ E3 [ &H -[9] O <3 K KJ & 9 `Q K & ( E P ) &/ ;E d4@ &H (ω Q ) &/ ;E d4@.[] Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 8 F" 8$ -3 - &+C \ G? K G<=.3 ^ K+ E. ; c&4 G (4) G &H? re c&4? H&/ X. ( D'& ;E D9& m F Y8 K K E. \ ^ E K</. E? G D'& ;3 ;4G c49e d.. :J Carrier-Based ;t [ K D&/ C K ^ E :4 G ' E `'-4 &+C > 'H ^ E F G<= & K ^ E d G<= &.3.. ;O & @8 D&/ :Kt -E --4 ic g & H ;3 4 K H&/ &?. ; &H D&/ 9<@ F & (5) G O + X E (6) G Y 9<@ ^ H&/ c&4.k G Y> @.K V C V C &H D&/ 9<@ :5 G V C +_ Voltage Controller I +_ Current Controller plant V C I ;3 < 9<@ 9<@ ^ D&/ :6 G Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

8 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J > K+. E /D&/? ^C././ E /D&/ F K & ;3 < D&/ 9<@ C?C K & ^ C K+. K;3 \./ J c&4 G<= `/+ \@7 / D&/ K C.H@ dm &.3 H9?. i w&3 &H 3 D&/ 9<@ K &H /D&/ 9<@ ^ /D&/?M.[]. &?/ s3 w> 4K-E C &<+ K 4K A K,9 ;3 < /D&/? K./ KJE E NB @. 3 "5 ( 5 - @J E =---4 &+C \ ;3 9<@ u& ;= (I ) Z< ;3 A> Ed.y@ & 4K ; K \ E 3 &H ) V i. ; E /D&/ ;3 9<@ G (7) G.[]. :. K Y c&4 E se. \+( I o [& K /. c&4 E se I (s)/v i (s) I s sc = + Vi s s C :O. K Y &4 9<@ E se + K. 4K ; ƒ' K / / / ; M +. Z< ;3 s3 ;G I s sk GC = I s + sk GC + s C c c I (6) (7) + D dm G ;3 /D&/ dm K c (8) G. (@ 4K A & ;3 /D&/ dm,+ A( &4 9<@ E se. X8 / 8 c&4 &+ K c.4 /. ; K c Z<&B 9 : K?BE K Y 3 9<@ @8.3 + I s sc I s + sk GC :C (9) G.. +?BE? K 3 ;3 9<@ K K+ 3E > 9 / JO K.. K+ K K 3 ) / ; < ;3 9<@ &4 9<@ E se Bode c (8) I I ( s) k c V ( s) i I I \ c&4 ;3 < 9<@ :7 G Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 8 6 Root ocus Imaginary Axis System: Gi 4 Gain:.4 Pole: -5e+3 Damping: Overshoot (%): Frequency (rad/sec): 5e+3 - -4-6 -9-8 -7-6 -5-4 -3 - - Real Axis ;3 9<@ ;G :8 G Bode Diagram Magnitude (db) Phase (deg) - - -3-4 9 45-45 -9 3 4 5 6 7 I I ( s) ( s) Frequency (rad/sec) E se bode :C :9 G $ C-' 5 J c95 =--3-4 (PI) H)& E /D&/ K & / \ (9) G Y < ;3 9<@ dm se 3E G J d3 t dc dm 3.. &4 9<@ dc dm?^ / D&/ &H ;E t K [ K &4.H@ d / d G<= 9 &.3?. ;t +. & PI /D&/ D& [ V C s I ( s) K I iωcut s sc KP + s + ωcut s + ω + KcGsC I I I o sc V C <( Hp 4K-E /D&/ : G K.5 H.. ; ω cut ; 4K-E /D&/ 3 &H 9<@ & () G s> `/+ 9E 4K /D&/ () G.[3].4 <= / 4K /D&/ K & ) 9E 8?I () G. ( I ) ;3 < /D&/ s3 ;= &H /D&/ 3 Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

83 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J K \+(. w45 [& ;= (I o ) ;3 GH@ s> `/+ dee. nb ((8) Y ) ;3 9<@ E se (9) Y &H 3 9<@ NB H' [& { ω } { ω ω } ω s K GC + s + K + K GC + s + K + K + K GC + + K = ( 9) 3 c p cut c c i cut c p ω ω cut 4K-E /D&/ 4K dm E dm dee K i K p +. nb () Y.4E K & @. <( Hp `/+ 4K-E /D&/ K i K p 9 :E K c&4 O 3 D & 7= ue _ ; /D&/ &.. i ;G <( Hp K i > K >?G 9 :E K `/+ C.H@ g & K.. & &4 /D&/? H9 \ X &.3. K+ /D&/ KGE D' F () G. =. D'& m D'& m 7= p ( + K p ) ( K GCω ) s : K GC + K + K ω + K GCω 3 c c i cut c s : + K + ω K GC ω + K p cut c p ωcut c s : ( + Kc + Ki ) ωcut + + K p + ωcut KcGC s : ω () 5 P r) E-4-4 F K 3E > 9 @ <( F 7= 3 &H K4G. 3 &H ;3 & Aq Xi@ E () G H&/ &. c& cj : \ &H 3 9<@ c& cj : Hp 4K J /D&/ () G Y G? @ 7ω 5ω 3ω ω `/+ `K H 4K-E /D&/.. &+C. : () Y &H / D&/ E se.. d G K ω s K ω s K ω s K ω s Gv ( s) = + + + + K s s s s i cut i3 cut3 i5 cut 5 i7 cut 7 + ωcut + ( ω ) + ωcut 3 + ( ω ) + ωcut 5 + ( ω ) + ωcut 7 + ( ω ) 7ω 5ω 3ω ω p d& `K dm dee K i7 K i5 K i3 K i E.q dm K p + /D&/ 4K dm K. 8 4/+ Hp cj : G Hp C.H@ (K i7 K i5 s> `/+ ω cut 7 ω cut5 ω cut3 ω cut?m K i3 ) c& cj : dh `/+ 4K K &? I 4.4E K & /D&/? <5E./ nb c&? 9,+.. d /D&/ ƒ+ ( K i7 K i5 K i3 G K.. :J Bode oe K+ @ / H@,/ c& cj F Hp (c& cj : F `/+ 4 db K &C K) K = K = K = Ω - /D&/ / dm?,+ &H. G Hp () G Y C.H@ dm i3 i5 i7 6 K../.+? ( F K &/ C.H@.. &+i :J G `/+ 4K /D&/ @8 Bode :C K &?. K43 E &H 9<@ &.3 ;O 3 D= 4K-E /D&/ &H () G.. D= [] lead-lag Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 84 / ƒ+ E 6 K ;3 /D&/. E Z< ;3 D&/ 9<@ F?&+C \ c&4 G g K c = G T : 5 (7) Y E dm /D&/ 3. ; K T D dm G E K+ 3 `&/ +. (@ ^ E s3 K+ &H E +M 3 ;K &H ;3 () V C Kiωcut s KP + s + ωcut s + ω + sτ α + sτ β I V C Kiωcut s KP + s + ωcut s + ω ω Ki cut s KP + s + ωcut s + ω Kiωcut s KP + s + ωcut s + ω G <( Hp 4K-E /D&/ : G Bode Diagram Magnitude (db) 5-5 - -5 9 Ki3=Ki5=Ki7= Ki3=Ki5=Ki7= Ki3=Ki5=Ki7=4 Ki3=Ki5=Ki7=6 d/e. Phase (deg) K i7 K i5 K i3 Z<&B 9 &H 9<@ Bode :C : G E 3 ;K s3 &H V c -9-8 -7 4 6 Frequency (rad/sec) : ; (3) () 3E ;E /D&/,B /E V = V V G s s I K G i c c v c E 3 ;K &H : (@ (4) V = G s V Z s I c c o o V c lead-lag K43 E se I = Io + scvc ( s) (3) / ic3 (3) () m :&4 ; > K m Y / E 3 `Q E se D&/ E se dee Z o (s) G(s) / (4) Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

85 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J G s Gv ( s) ( s) kcg = + r + k G Cs + Cs + G s s k G c v c (5) Z o ( s) r + kcg + s = + r + k G Cs + Cs + G s s k G c v c : (7) Y &H 9<@ K 9<@ E se. &H 9<@ &4 9<@ E se G(s) (5) G op ( s) Gv ( s) ( s) kcg ( r k G) Cs Cs = + + + c (6) (7) ' 8-AQ-5 &H / 5 ;4G A( E 3 D'& ;3 c49e H&/ X H9? ;E 5 & ^ E K G<=,B?. & 3 3 &H HE ;O K ` K+ 99@ ;E &+ NB `Q &+C > K+ 99@.. &+C > KJ 3 `Q 9<@ K & s3 ; 5 == @ ' M--5 &H. K?BE K CK D) me E =J me HE 99@ ;E - & K Y 99@ \5H ;E?'E.3 P = V I i Q i c o I o c o E =J 3 ;3 ( 9 ) = V I ;E 5.3 3-9 K+.. \5H ;E ) c F ;O s> `/+ /. & ic? &<+ K?.O. K+ 99@ ;E 9 6J K ;E ( B Hp Q i P i V c E 3 ;K : (8) Q i \5H 99@ ;E P i + / Hp Xi@.3.. K.. &+C \ G `/+ ; 5 == @ ' ; %& --5 Q 3ph P 3ph ) K+ 99@ ;E 9 _ ;E KGE 9 5 ic? &<+ K & H 99@ ;E 9 K & K+ s3 &H K `/+ 9. 99@ ;E.~ Hp ) E? K. :. 5 > K Y Q 3ph P 3ph m = 3ph = a + b + c E E np E n P P P ref = + mq3 ph = + m Qa + Qb + Qc ω ω ω (9) `/+ E K+ &H s3 9 dee ω E &/ &/ ;E &+ dm dee m n + sm & 9? / E &H K K+ K?'E J &+ ANB +. E.[7] /? E.H@ ^ ;3 / Xi@.3 D'E Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 86 a 5= J5 sx =- D, RJ c95 9 '-3-5 : (@ K m b K+ s3 &H >,B K HE (ω ref ) `/+ ( E m ) &H K K & sin ( ω ) ( ω ) ( ω ) V Em ref t RD Ioa ca V E t R I V cc E t + R I cb = m sin ref D ob m sin ref D oc (). KJ & 9 3 `Q ) R D + c&4 :C <. 4K-E D&/ b ^ E &H D&/ 9<@ :C < ) (3) G.. ; (4) G E s3 &H HE.3 &+ [ & ^ K E D&/ V C I V i V C ω 3ω 5ω 7ω &+ [ & D&/ c&4 :C < :3 G I V C V ca V cb V cc I oa I ob I oc P a P b P c Q a Q b Q c P 3 ph Q 3 ph n m E ω E m ω ref RDIoa RDIob RDIoc V ca V cb V cc &+ [ & D&/ c&4 :C < :4 G M) _-6 m5 G @ K ^ E G<= c&4 G<=.5( \. 3 () D3 E H&/ & A> &.. K Matlab\Simulink N& E =J F q / E ( K K c&4 G G<=.3 &+ D&/ / H9? H= &+ D&/ c&4 G<= 49.3. +M D D'& F q / \5H ;E d4@ `/+ &+ D& c&4 ( E P ) o& K ^ K+ E &+ D& c&4 ( E Q ) &/ ;E d4@ &H (ω Q ) &/ ;E d4@ `/+ &/ ;E d4@ &H (ω P ) &/. 49 c c&4 ;3 c49e 3 G / ). ; K E =J me HE K+ &H (5) G. K+ A( HE &H D'& Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

87 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J Voltage (v) 4 3 - - -3-4..4.6.8...4.6.8. Time (sec) 9 38v 5 khz / mh / Ω µ F 8 v /8 Ω /5 Ω /8 Ω 6 Ω 6 Ω 6 Ω 3 /4 rad / sec 94 /3 rad / sec 57 /8 rad / sec 9 /9 rad / sec 8 µ sec 5 µ sec /8-3 rad/sec/var /8 - V/W 3 /5 Ω K ^ E 3 &H :5 G H&/ & A> 9 : D3 K & (V o ) 3 m &H (f) K</ `/+ () K+ 3 Z< (R) K+ 3. 9 (C) K+ 3 ;K DC FH &H (k c ) ;3 < 9<@ E /D&/ dm (k p ) &H 9<@ /D&/ E dm (k i ) <( Hp 4K /D&/ dm (k i3 ) : F 4K /D&/ dm (k i5 ) cj F 4K /D&/ dm (k i7 ) c& F 4K /D&/ dm ( ω cut ) <( Hp 4K /D&/ s> `/+ (ω cut3 ) : F 4K /D&/ s> `/+ (ω cut5 ) cj F 4K /D&/ s> `/+ ( ω cut7 ) c& F 4K /D&/ s> `/+ (τ α ) ) (τ β lead-lag /D&/.q dm lead-lag /D&/.q dm (n) 99@ ;E &+ dm (m) ;E &+ dm (R D ) KJ & 9 `Q Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 88 F q / \5H. nb G / ).. ; me / ;3 (6) G / \5H d G G<= iue d G<= 7= K G K.. +M D'& Current (A) 4 3 - - -3 K ^ E 3 D'& K+ ;3 :6 G.. > q -4..4.6.8...4.6.8. Time (sec) 4 3 oad Current Inv Current Inv Current Currant (A) =J K / / K+ ;3 ;4G.+y K E K :/ K+ F ;3 :7 G.. ; K+ K G =J K / / ;3 E K :/ 3 ;3 (7) G - G? K.&4 Y c c 7 / E 3 ;3 E.+y 3E G? - ;3 (8) G. 3 E? ^ ;3 _ / = = H&/ c&4 /.+C J& ;E ) G? /. ; ~ c ;3 (9) G. ; E K :/ 3 K+ K G<= ( E Q ) - - -3-4..4.6.8...4.6.8. Time (sec). E? ;3 c49e H&/ c&4 Y> G<= (ω P ) D& &+ c&4 KJ `Q & &+ D&/ c&4 G<= 49 &+ D&/ c&4.5e ;E c49e 5 ) () G / &+C > D& &+ D&/ ^ E A\5H J E? 9> ;3 c49e H&/ c&4?. nb G / ). D&? / c ' E ;3 E F.~ ;3 ( 3 / ( K =.3. E? ^ ;3 3 ) Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

89 D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J Na-7?.. D'& @ K ^ K+ E /D&/ @8 H9? < 9<@ E /D&/ D'& @ c&4 d G<= & \. @8 <@ <@ /D&/ & &H 3 9<@ 4K-E /D&/ ;3 KK.3 3 & 9 KJ `Q K & &+ D&/ [ E @? K <(+ 3 ƒ+? Y> ;3 c49e & D'& D'& iue E c&4.. & E - ; c&4 d G<= K o&./? E &H K E. 5 Current (A) 5-5 - -5 -..4.6.8...4.6.8. Time (sec) (ZH) 5 Current (A) 5-5 - -5 -..4.6.8...4.6.8. Time (sec) (w) (w ZH) K E K+ ;3 :8 G Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J 9 3 Neutral current (A) - - -3..4.6.8...4.6.8. Time (sec) ~ c ;3 :9 G 4 3 oad Current Inv Current inv Current Current (A) - - -3 -.9.93-4..4.6.8...4.6.8. Time (sec) D&/ c&4.5e =J K / / K+ ;3 ;4G.+y K E K :/ K+ F ;3 : G D& &+ RJ-8 [] Eyyup Demirkutlu, Suileyman Qetinkaya, Ahmet M. Hava, Output Voltage Control of A Four-eg Inverter Based Three-Phase UPS by Means of Stationary Frame Resonant Filter Banks, European Conference on Power Electronics and Applications, pp. -, 7. [] Comparison Transformerless to Transformer-based UPS Design, EMERSON Network Power. [3] M. Prodanovi c and T.C. Green, Control and filter design of three-phase inverters for high power quality grid connection, IEEE Trans. Power Electron., vol. 8, no., pp. 373 38, 3. [4] P. Verdelho and G. D. Marques, Four-wire current-regulated PWM voltage converter, IEEE Trans. Ind. Electron., vol. 45, no. 5, pp. 76 77, Oct. 998. [5] Jun iang, Tim C. Green, Chunmei Feng, George Weiss, Increasing Voltage Utilization in Split-ink, Four-Wire Inverters, IEEE Trans. Ind. Electron. vol. 4, no. 6, pp. 56-569, June 9. [6] J. De Kooning, B. Meersman, T. Vandoorn, B. Renders,. Vandevelde, Comparison of Three-Phase Four-Wire Converters for Distributed Generation, 45th International Universities Power Engineering Conference (UPEC), pp. -6,. [7] J.M. Guerrero, J. Matas, uis Garcia de Vicuna, M. Castilla, J. Miret, Decentralized Control for Parallel Operation of Distributed Generation Inverters Using Resistive Output Impedance, IEEE Trans. Ind. Electron., vol. 54. No., 7. Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39

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D'& iue.3 &+ G<= & K ^ E /D&/ @8 3 ; <= ;5 N?4@ J [3] Y. W. i, F. Blaabjerg, D. M. Vilathgamuwa, and P. C. oh, Design and comparison of high performance stationary-frame controllers for DVR implementation, IEEE Trans. Power Electron., vol., no., pp. 6 6, Mar. 7. 9 Journal of Nonlinear Systems in Elect. Eng., Vol., No, Fall 3 39