Power Flow Control of Grid-Connected Fuel Cell Distributed Generation Systems

Transcription

1 Jounal of Electical Engeeg & Technology, Vol. 3, No., pp. 43~5, Powe Flow Contol of Gid-Connected Fuel Cell Ditibuted Geneation Sytem Am Hajizadeh and Maoud Aliakba Golka* Abtact Thi pape peent the opeation of Fuel Cell Ditibuted Geneation (FCDG) ytem ditibution ytem. Hence, modelg, contolle deign, and imulation tudy of a Solid Oxide Fuel Cell (SOFC) ditibuted geneation (DG) ytem ae vetigated. The phyical model of the fuel cell tack and dynamic model of powe conditiong unit ae decibed. Then, uitable contol achitectue baed on fuzzy logic and the neual netwok fo the oveall ytem i peented ode to activate powe contol and powe quality impovement. A MATLAB/Simulk imulation model i developed fo the SOFC DG ytem by combg the dividual component model and the contolle deigned fo the powe conditiong unit. Simulation eult ae given to how the oveall ytem pefomance cludg active powe contol and voltage egulation capability of the ditibution ytem. Keywod: Ditibuted Geneation, Fuel Cell, Powe Flow Contol, Powe Quality. Intoduction Recently, powe maket libealization ha eulted an ceae the numbe of malle powe poduce paticipatg the electicity maket givg ie to a enewed teet fo ditibuted geneation (DG). Thi led to a conideable ceae the popotion of DG the netwok [, ]. The toduction of DG to the ditibution ytem ha a ignificant impact on the flow of powe and voltage condition to the cutome and utility equipment. Thee impact might be poitive o negative dependg on the ditibution ytem opeatg chaacteitic and the DG chaacteitic. Poitive impact clude voltage uppot and impoved powe quality, diveification of powe ouce, eduction tanmiion and ditibution loe, tanmiion and ditibution capacity eleae and impoved eliability [3]. The tegation of DG with the utility ditibution netwok offe a numbe of technical, envionmental, and economical benefit. Moeove, uch tegation allow ditibution utilitie to impove the netwok pefomance by educg it loe. The exitg DG unit ae utilized to upply active powe to eithe the netwok o the cutome. Although DG unit uch a fuel cell, photo voltaic, mico tube, and toage device, which ae lked via a nonlea teface, epeent a mall potion of the talled DG capacity, they will potentially gow. Uually, thi teface conit of a Coepondg Autho: Electical Engeeg Depatment, K.N. Tooi Univeity of Technology, Tehan, Ian (amhajizadeh@ee.kntu.ac.i) * Electical Engeeg Depatment, K.N. Tooi Univeity of Technology, Tehan, Ian. (golka@eetd.kntu.ac.i) Received 7 Novembe, 007; Accepted: 8 Decembe, 007 cuent contolled Voltage Souce Invete (VSI). With the new ea of ytem etuctug, the quality of powe ga ceag attention. [4]. Among the new fom of DG, the natual-ga-fed fuel cell that convet chemical enegy diectly to dc how a pomig futue. Seveal type of FC fo a vaiety of application ae unde active eeach [5, 6]. Fuel Cell DG (FCDG) ytem can be tategically placed at any ite a powe ytem (nomally at the ditibution level) fo gid efocement, theeby defeg o elimatg the need fo ytem upgade and impovg ytem tegity, eliability, and efficiency. Theefoe, pope contolle need to be deigned fo a FCDG ytem to make it pefomance chaacteitic a deied [7, 8]. A geat deal of eeach ha been done on powe electonic device fo gidconnection of FCDG ytem ditibution ytem [9-3]. Howeve, mot of the elated pape have not addeed detail the modellg and contol of powe convete and fuel cell ditibuted geneato. In [4] novel hieachical contol achitectue fo a hybid ditibuted geneation ytem that conit of dynamic model of a battey bank, a olid oxide fuel cell and the powe electonic convete ha been peented. But thi pape the voltage egulation capability and eactive powe contol of FCDG have not been addeed. Alo [5] the flexible contol tategy fo gid-connection of fuel cell ditibuted geneation to impove the powe quality and active powe contol ditibution ytem ha been peented. Nevethele, fo pactical analyi of the fuel cell ytem, a fit/econd ode model [6] i ued to ealize the low dynamic of the fuel cell.

2 44 Powe Flow Contol of Gid-Connected Fuel Cell Ditibuted Geneation Sytem So it i impotant to develop a pope modelg of the FCDG ytem and deign uitable contol tategie fo all component to atta good pefomance uch a optimal opeation of fuel cell tack and powe quality impovement. Hence, thi pape the telligent contol tuctue ha been developed fo a FCDG ytem with active powe management and eactive powe contol capability. The fuel cell powe plant i tefaced with the utility gid via boot DC/DC convete and a thee-phae pule width modulation (PWM) vete. A validated SOFC dynamic model, epoted [7], i ued thi pape. The model fo the boot DC/DC convete and the thee-phae vete togethe ae alo addeed. The contolle deign methodologie fo the DC/DC convete and the thee-phae vete ae alo peented fo the popoed fuel cell DG ytem. Baed on the dividual component model developed and the contolle deigned, a imulation model of the SOFC DG ytem ha been built MATLAB/Simulk envionment. Simulation eult how the active powe contol and voltage ag mitigation by FCDG ytem.. Dynamic Modelg of FCDG Sytem The dynamic modelg of a Fuel Cell Ditibuted Geneation (FCDG) ytem i an impotant iue that need to be caefully addeed. To tudy the pefomance chaacteitic of FCDG ytem, accuate model of fuel cell ae needed. Moeove, model fo the tefacg powe electonic cicuit a FCDG ytem ae alo called fo to deign contolle ode fo the oveall ytem to impove it pefomance and to meet ceta opeational equiement [4]. Conceng the ytem opeational equiement, a FCDG ytem need to be tefaced though a et of powe electonic device. Fig. how the block diagam of the FCDG ytem popoed thi pape. The electic component of the FCDG ytem ued thi pape compie a battey, DC/DC and DC/AC convete, while the electochemical component i a Solid Oxide Fuel Cell ytem (SOFC). The mathematical model decibg the dynamic behavio of each of thee component ae given below.. Fuel Cell Model Fuel cell ae tatic enegy conveion device that convet the chemical enegy of fuel diectly to electical enegy. They how geat pomie to be an impotant DG ouce of the futue due to thei numeou advantage, uch a high efficiency, zeo o low emiion (of pollutant gae), and flexible modula tuctue. The model of SOFC powe plant ued thi tudy i baed on the dynamic SOFC tack model developed and validated [7]. The pefomance of FC i affected by eveal opeatg vaiable, a dicued the followg. Deceag the cuent denity ceae the cell voltage, theeby ceag the FC efficiency. One of the impotant opeatg vaiable i the eactant utilization, Uf, efeg to the faction of the total fuel (o oxidant) toduced to a FC that eact electochemically: U f out q q q H H H = q q H H = () Whee q H i the hydogen mola flow. High utilization ae conideed deiable (paticulaly malle ytem) becaue they mimize the equied fuel and oxidant flow, fo a mimum fuel cot and compeo load and ize. Howeve, utilization that ae puhed too high eult ignificant voltage dop. The SOFC conit of hunded of cell connected eie and paallel. Fuel and ai ae paed though the cell. By egulatg the level, the amount of fuel fed to the fuel cell tack i adjuted, and the output eal powe of the fuel cell ytem i contolled. The Nent equation and Ohm law deteme the aveage voltage magnitude of the fuel cell tack [8]. The followg equation model the voltage of the fuel cell tack: V fc 0.5 RT PH P O N0 ( E0 + (ln( )) I f 0 F PH O = () whee: N 0 i the numbe of cell connected eie; E 0 i the voltage aociated with the eaction fee enegy; R i the univeal ga contant; T i the tempeatue; I f0 i the cuent of the fuel cell tack; F i the Faaday' contant. P H, P HO, P O ae detemed by the followg diffeential equation: Fig.. Fuel Cell Ditibuted Geneation Sytem Stuctue. PH = t H. PH ( O = PH O + t H O K H O. PO = t O ( PH ( PO + K H + K O ( q H ( q O K I fc )) K I fc )) K I fc )) (3)

3 Am Hajizadeh and Maoud Aliakba Golka 45 Whee, q H and q O ae the mola flow of hydogen and oxygen and whee the K contant i defed by the elation between the ate of eactant hydogen and the fuel cell cuent: q H N 0 I = = K I (4) F. DC/DC Convete Model Uually to connect a fuel cell to an extenal powe ytem, it i neceay to boot the fuel cell voltage o to ceae the numbe of cell. The ole of the DC/DC boot convete i to ceae the fuel cell voltage, to contol the fuel cell powe, and to egulate the voltage. Fig. how the DC/DC convete model. Thi boot convete i decibed by the followg two non-lea tate pace aveaged equation [4]: Whee k= {a, b, c}. To develop the dynamic model, the tate equation (6) ae tanfomed to the ytem ynchonou efeence fame a: di q R ω ω = iq ω id + m ( δ + dt L L di d R ω ω = id + ω iq + m co ( δ + dt L L θ ) Vdc ( L θ ω ω θ ) Vdc co( L ) V θ ) V (7) ( d) d ρx = X + U L L ( d) X ρx = X C RC (5) Fig. 3. Thee-phae dc/ac voltage ouce vete Whee d i the on time of the witchg device, U i the put voltage, X i the ducto cuent and X i the output voltage..4 Ditibution Sytem Model To tudy the dynamic impact of the fuel cell powe plant on the powe ditibution ytem, the thee-phae ytem ha been epeented by a gle le equivalent ytem. Fig.. DC/DC Convete Model.3 DC/AC Convete Model By fa the motly ued convete nowaday i the Voltage Souce Convete (VSC). A dynamic model of the voltage ouce vete ha been developed. A thee-phae equivalent cicuit of DC/AC convete i hown Fig. 3. To educe hamonic, filte ae connected between the convete and the gid. A fit-ode filte, epeented by the L and the R Fig. 3, i ued. In Fig. 3, v ia, v ib and v ic ae the thee-phae AC voltage output of the vete, and i a, i b, i c ae the thee-phae AC cuent output of the vete. The bu voltage of the gid ae v a, v b and v c. The dynamic model of the thee-phae VSC i epeented [9]. dik R = ik + ( vik vk ) (6) dt L L 3. Contol Stategy fo FCDG Sytem Thee i a high demand fo utility DG tallation due to thei advantage of defement o upgadg the ditibution fatuctue. Mot DG unit ae connected to the ditibution ytem though a hunt nonlea lk uch a a Voltage Souce Invete (VSI) o a Cuent Souce Invete (CSI). The ma function of the hunt connection i to contol the amount of active powe dawn fom the DG ouce. Thi lk can emulate DSTATCOM device by contollg the eactive powe, a well a the active powe. Hence, it i neceay to deign a contol tuctue to manage active powe and eactive powe imultaneouly. Moeove, the contol tategy mut be deigned to mitigate diffeent powe quality poblem. Alo, a uitable contol i peented to egulate the put fuel flow ode to meet a deiable output active powe demand and to pevent tanient condition the fuel cell tack. The contol tuctue that ha been popoed thi pape ha been peented Fig. 4. A dicated, thi tuctue ha been compoed of diffeent local unit.

4 46 Powe Flow Contol of Gid-Connected Fuel Cell Ditibuted Geneation Sytem Fig. 4. Contol Stuctue of Fuel Cell Ditibuted Geneation Sytem Uage of ditibuted fuzzy logic contolle thi tuctue caue it to have adaptive popetie ditibution ytem [5]. The upeioity of FLC i the eult of it ability to manage the nonlea behavio of many pactical ytem of complex contol tuctue by takg advantage of heuitic and expet knowledge of the poce beg contolled. The fuzzy logic contolle ued thi eeach conit of ule bae, fuzzification, feence enge, and defuzzification. The ule bae collect the contol ule which decibe the expet knowledge and expeience the fuzzy et. In the fuzzification poce, the numeical put ae conveted to lguitic fuzzy value. Then, fom the fuzzy value and the aleady etablihed ule bae, lguitic contol value ae geneated the feence enge. Becaue thee lguitic feence eult cannot be ued the actuato diectly, they hould be conveted to numeical output aga the defuzzification poce. MAX-MIN compoition and the cente of gavity method ae utilized the feence enge and defuzzification of thi fuzzy logic, epectively. 3. DC/AC Convete Contolle Powe quality ha attacted conideable attention fom both utilitie and ue due to the ue of many type of enitive electonic equipment, which can be affected by hamonic, voltage ag, voltage well, and momentay teuption [9]. Thee ditubance caue poblem, uch a oveheatg, moto failue, accuate meteg, and miopeation of potective equipment. Voltage ditubance i the mot common powe quality poblem dutial ditibution ytem. The voltage ditubance maly encompae voltage ag, voltage well, voltage hamonic, and voltage unbalance. The voltage ditubance notoiouly affect voltage-enitive equipment that eventually lead to malfunction. Voltage ag i one of the mot evee powe quality poblem becaue of it advee fancial impact on cutome. The powe quality contol unit, a hown Fig. 5, ha been fomed of two pat, the voltage poceg unit and fuzzy logic contolle. Fig. 5. DC/AC Convete Contolle 3.. Voltage Poceg Unit Thi unit i baed on Adaptive Lea Neuon tuctue (ADALINE). In ecent yea, with the development of atificial telligence technique, ADALINE ha been ued to analyze the powe quality [0]. The idea behd ug the ADALINE detection of powe quality ditubance i to epeent the ADALINE a an adaptive ignal pedicto []. The put to thi pedicto ae time-delayed ample

5 Am Hajizadeh and Maoud Aliakba Golka 47 of the ignal and the output of the ADALINE i the pedicted value of the ignal. The ADALINE algoithm poee a highly tackg capability. Yet when a powe quality ditubance occu, the abupt change the ignal give ie to the eo ignal geneated by the ADALINE, and the weight value expeience vaiation until they ettle down to the new value. Both the alteation the eo ignal and the um of the vaiation of the weight value can aid the detection of powe quality event. To achieve the voltage egulation tak, the cuent i q-ef i aigned to the output of the Fuzzy Logic Contolle (FLC). The actual put to the fuzzy ytem ae caled veion of both the m voltage eo and it deivative. Seven unifomly ditibuted tiangle membehip function ae ued fo the fuzzification of the put. Each of the FLC put and output ignal ae fuzzy vaiable and ae aigned even lguitic vaiable, namely, NB, NM, NS, Z, PS, PM, and PB, which tand fo negative big, negative medium, negative mall, zeo, poitive mall, poitive medium and, poitive big, epectively. The ule bae i deigned o that the actual m voltage can each it command value a quickly a poible with the hunt compenato limitation without ovehoot. Thi lead to the ule a lited Table I. e Table. Fuzzy Rule Bae fo Voltage Regulation Δ iq_ef e NB NM NS Z PS PM PB NB PB PB PB PM PM PM PS NM PB PB PM PM PM Z NB NS PB PM PM PM PS NS NB Z PB PM PS Z NS NM NB PS PB PS NS NM NM NM NB PM PB Z NM NM NM NB NB PB NS NM NM NM NB NB NB 3.. Active Powe Contol A fuzzy logic contolle ha been deigned to contol active powe dawn fom the load. The actual put to the fuzzy ytem ae caled veion of both the active powe eo and it deivative and the cuent i d-ef i aigned to the output of the FLC. Seven unifomly ditibuted tiangle membehip function ae ued fo the fuzzification of the put. Each of the FLC put and output ignal ae fuzzy vaiable and ae aigned even lguitic vaiable, namely, NB, NM, NS, Z, PS, PM, and PB, which tand fo negative big, negative medium, negative mall, zeo, poitive mall, poitive medium and, poitive big, epectively. The fuzzy ule bae ha been hown Table. e Table. Fuzzy Rule Bae fo Active Powe Contol Δ id_ef NB NM NS Z PS PM PB NB NB NB NB NB NM NS Z NM NB NB NB NM NS Z PS NS NB NM NS NS Z PS PM Z NB NM NS Z PS PM PB PS NM NS Z PS PM PM PB PM NS Z PS PM PB PB PB PB Z PS PM PB PB PB PB 3. DC/DC Convete Contolle The unegulated output voltage of the FC i fed to the DC/DC boot convete. Beg unegulated it ha to be adjuted to a contant aveage value (egulated dc voltage) by adjutg the duty atio to the equied value. The voltage i booted dependg upon the duty atio. The duty atio of the boot convete i adjuted with the help of a fuzzy logic contolle (FLC). The duty atio i et at a paticula value fo the convete to povide deied aveage value of voltage at the output, and any fluctuation the FC voltage, due to change fuel flow, the load o the chaacte of FC due to the chemity volved, take the output voltage away fom the deied aveage value of the voltage. The FLC change the duty atio appopiately to get the deied aveage value. The boot convete epond fat to the change the duty atio. The duty atio of the convete i changed by changg the pule fed to the witch the DC/DC convete cicuit by the PWM geneato. The fuel flow mut alo be adjuted, which take effect gadually and contol the output voltage. Thu, both tategie have to be combed fo the efficient contol of voltage of the FC. Thi pape concentate only on the boot convete contol tategy. The epone time of the DC/DC convete i vey hot compaed to that of the efome of the FC, which alte the fuel flow. Conequently, fo fat ytem epone, itially the convete i contolled fo load vaiation and the aveage voltage i adjuted the tanitional peiod by the boot convete. The output of the DC/DC convete i the booted voltage that i fed to the load o to the next tage of filte to eventually pa on to the vete tage. Thi booted voltage i compaed with a efeence dc voltage to geneate an eo ignal. The change eo i calculated. The eo and the change eo ae fed a put to the FLC. The FLC geneate a contol ignal baed upon the put and the ule bae. The contol ignal i fed to the PWM geneato. The PWM geneato, baed upon the contol ignal, adjut the pule of the witch of the boot convete. The boot convete geneate output voltage baed upon the duty atio povided by the PWM geneato. e

6 48 Powe Flow Contol of Gid-Connected Fuel Cell Ditibuted Geneation Sytem The fuzzy ule bae fo duty atio contol of the DC/DC convete ha been peented Table 3. Table 3. Fuzzy Rule Bae fo Duty Ratio Contol of DC/DC Convete e Δd NB NM NS Z PS PM PB NB NB NB NB NB NM NS Z NM NB NB NB NM NS Z PS NS NB NM NS NS Z PS PM Z NB NM NS Z PS PM PB PS NM NS Z PS PM PM PB PM NS Z PS PM PB PB PB PB Z PS PM PB PB PB PB 3.3 Fuel Cell Contolle In ode to opeate the fuel cell tack at an optimal fuel utilization pot (appoximately 85%) [], the contol algoithm hould obeve the followg opeational contat of the fuel cell ytem: Undeued fuel: If fuel utilization dop below a ceta limit, the cell voltage will ie apidly. Oveued fuel: If fuel utilization ceae beyond a ceta value, the cell may uffe fom fuel tavation and be pemanently damaged. Unde voltage: The fuel cell chaacteitic poe a lowe cell voltage limit of appoximately 0.5 V, beyond which the cell voltage deceae vey teeply with ceag cuent [4]. To meet the afoementioned uage equiement, the baic taget of the fuel cell contolle i to mata optimal hydogen utilization, U f,opt, aound 85%. Equation (3) how that the eactg fuel quantity, q, i diectly popotional to the output cuent, I, beg the facto K, which i a cell contant. Hence, the deied utilization i tanlated to the coepondg output cuent demand: e H elated to it fuel conumption at the elected optimum opeatg pot of the V-I chaacteitic. Opeatg the fuel cell at diffeent output powe level equie uitable vaiation of it put fuel flow ate, to be ealized by the oveall contol ytem of the fuel cell. The powe demand equiement of the fuel cell i tanlated to a cuent demand put by dividg by the tack output voltage: Pdemand V fc I = (0) demand To ovecome the tanient condition the fuel cell, a fuzzy logic contolle ha been deigned. The actual put to the fuzzy ytem ae caled veion of both the fuel cell cuent eo and it deivative, and the hydogen mola flow q H-ef i aigned to the output of the FLC. Seven unifomly ditibuted tiangula membehip function ae ued fo the fuzzification of the put. Thi lead to the ule a lited Table IV. Each of the FLC put ignal and output ignal ae fuzzy vaiable and ae aigned thee lguitic vaiable, namely, S, M, L, N, Z and P, which tand fo mall, medium, lage, negative, zeo, and poitive, epectively. Howeve, fo peventg tanient condition on the output voltage of the fuel cell, the ule bae of the FLC mut be deigned coectly. The contol tuctue fo the fuel cell ytem ha been hown Fig. 6. Table 4. Fuzzy Rule Bae fo the Hydogen Mola Flow of the Fuel Cell e Δq H-ef N Z P S NL Z PS M NS Z PS L NS PS PL e q U = q (8) K f opt I demand I H demand =, U f, opt K H A typical ange of U f i 80-90% ([]), which enue that the opeational limit mentioned above ae obeved. The coepondg limitation fo the demand cuent i then: 0.8q K H H 0.9q = I fc _ m I fc _ ef I fc _ max = (9) K Unde thee condition, the cell output powe i diectly Fig. 6. Fuel Cell Contolle 4. Simulation Reult The topology ued thi tudy fo the fuel cell ytem, powe condition unit, and utility gid i hown Fig. 7. The pefomance of the popoed tuctue i aeed by a compute imulation that ue MATLAB Softwae. The paamete of the ytem unde tudy ae given Table 5.

7 Am Hajizadeh and Maoud Aliakba Golka 49 Fig. 7. Block diagam of popoed model The cae tudy i dedicated to tet the dynamic pefomance of the popoed tuctue. In a fuel cell DG ytem, a ceta amount of powe may be cheduled to be deliveed to a load cente fom the utility gid with the et to be upplied by the fuel cell ytem. In thi cae tudy the fuel cell powe i et to 00 kw ( p.u.). Voltage ag will be ued to exame the dynamical pefomance of the algoithm. It i aumed that the thee phae voltage wee balanced until a ditubance Table 5. Fuel Cell Ditibuted Geneation Sytem Paamete Fuel Cell Paamete Faaday contant (F) [C/kmol] Hydogen time contant (t H ) 6. [ec] Hydogen valve mola contant(k H ) k Contant=N 0 /4F No Load Voltage (E 0 ) 0.6 [V] Numbe of Cell (N 0 ) 384 Oxygen time contant (t O ).9[ec] Oxygen valve mola contant (K O ) FC tenal eitance () FC abolute tempeatue (T) 0.6 [Ω] 343 [K] Univeal ga contant (R) [J/(kmol K)] Utilization Facto (U f ) 0.8 Wate time contant (t HO ) 78.3 [ec] Wate valve mola contant (K HO ) Rated voltage (V) Reitance (R) Capacitance (C) Inducto (L) Rated Voltage (V) Rated Powe (W) R (Ω) L (H) f (Hz) DC/DC Convete Paamete 00V/540V.3 [Ω].5 [mf] 45 [μh] DC/AC Convete Paamete 540V dc/0v ac 00KW 0.9(mΩ) 0.0(mH) 50(Hz) ha occued the ytem at 0.5 econd. The ditubance caue a voltage ag the thee voltage, a hown Fig. 8. Befoe the ditubance, the ytem wa balanced and, theefoe, the negative component vanihe. The voltage at the PCC i equal to.0 pu dug nomal opeation. At t=0.05 ec, the ditibuted enegy ouce i witched on to coect the voltage pofile. At 0.5 econd, the voltage ag i itiated and the popoed algoithm ucceed to detect the ditubance le than half of a cycle. The ignal of voltage pedicted by the ADALINE tuctue ha been peented Fig. 9. A hown Fig. 9, The ADALINE algoithm poee a high tackg capability. Fig. 0 demontate that the popoed contol tuctue baed on Fuzzy Logic Contol ucceed egulatg the PCC voltage at.0 pu, even when the load ditubance occu at 0.5ec and 0.5ec with fat dynamic and mimum ovehoot. Thi eult exame the ditubance ejection capabilitie of the popoed FLC. It quickly etun the voltage at the PCC to it ettg value. Fig. (a) dicate that the active powe upplied fom the fuel cell DG i almot contant, and i equal to it put Fig. 8. Thee-phae Supply Voltage Dug a Sag Fig. 9. Pedicted Voltage Sag by ADALINE

8 50 Powe Flow Contol of Gid-Connected Fuel Cell Ditibuted Geneation Sytem command value (pu) fom the contol cicuit. Fally, Fig. (b) how the jected eactive powe fom the FCDG ytem to compenate fo the voltage. It i clea fom Fig. (a) and (b) that the contol of the active and eactive powe i dependent of each othe. Fig. how the output voltage change of the fuel cell. A depicted thi ame figue, the voltage deceae when the active powe ceae. The fuel cell voltage ha not been affected dug the voltage ag. 5. Concluion Thi pape peent a new appoach fo active powe contol and powe quality impovement a fuel cell ditibuted geneation ytem. Modelg, contol, and imulation tudy of a SOFC DG ytem ae vetigated thi pape. A validated SOFC dynamic model i ued to model the fuel cell powe plant. The tate pace model fo the boot DC/DC convete and the thee-phae vete ae alo dicued. Then, by deigng pope telligent contolle, the capability of FCGD fo active powe contol and voltage ditubance mitigation ha been demontated. The popoed contol method i enitive to the paamete vaiation of the ditibution ytem, becaue it i adaptive natue. Thi i an abolute neceity ditibution ytem, ce thee i no dependence on the paamete of the electical netwok. Refeence Fig. 0. Regulated Voltage (pu) at PCC Fig.. Poduced Active and Reactive Powe by FCDG Fig.. Fuel Cell Voltage Dug Voltage Sag [] I. El-Samahy, Ehab El-Saadany, The Effect of DG on Powe Quality a Deegulated Envionment, Powe Engeeg Society Geneal Meetg, June 005, IEEE. [] Sh.Hoezadeh, M.A.Golka, Sh.Shoki, A.Hajizadeh, RELIABILITY IMPROVEMENT AND LOSS REDUCTION OF DISTRIBUTION SYSTEM WITH DISTRIBUTED GENERATION, Intenational Powe Sytem Confeence (PSC006), 3-5 Nov. 006, Tehan-Ian. [3] P.R. Khati, Membe, V.S. Jape, N.M. Lokhande, B.S. Motlg, Impovg Powe Quality by Ditibuted Geneation, The 7th Intenational Powe Engeeg Confeence (IPEC), DEC [4] Cutom Powe Technology Development, 999. IEEE P409 Ditibution Cutom Powe Tak Foce. [5] Kwang Y. Lee, The Effect of DG Ug Fuel Cell unde Deegulated Electicity Enegy Maket, IEEE 006. [6] Rahman S.: Fuel cell a a ditibuted geneation technology. In Poceedg of IEEE powe engeeg ociety umme meetg, 00. p. 55. [7] Z. Miao, M. A. Choudhy, R. L. Kle, and L. Fan, Study of a fuel cell powe plant powe ditibution ytem Pat I: Dynamic model, Poc. IEEE PES Geneal Meetg, Denve, CO, Jun [8] C. J. Hatziadoniu, A. A. Lobo, F. Pouboghat, M. Danehdoot, A Simplified Dynamic Model of Gid- Connected Fuel-Cell Geneato, IEEE TRANSACTIONS ON POWER DELIVERY, VOL. 7, NO., APRIL 00. [9] Kouoh Sedghiigachi, Ali Feliachi, Dynamic and

9 Am Hajizadeh and Maoud Aliakba Golka 5 Tanient Analyi of Powe Ditibution Sytem with Fuel Cell Pat II: Contol and Stability Enhancement, IEEE TRANSACTIONS ON ENERGY CONVERSION, VOL. 9, NO., JUNE 004. [0] Valey Knyazk, Lennat S ode Claudio Canizae, Contol Challenge of Fuel Cell-Diven Ditibuted Geneation, Pape accepted fo peentation at 003 IEEE Bologna PoweTech Confeence, June 3-6, Bologna, Italy. [] B. Delfo, F. Fonai, Modelg and Contol of an Integated Fuel Cell-Wd Tube Sytem, Pape accepted fo peentation at 003 IEEE Bologna PoweTech Confeence, June 3-6, Bologna, Italy [] Kouoh Sedghiigachi,Ali Feliachi, Impact of Fuel Cell on Load-Fequency Contol Powe Ditibution Sytem, IEEE TRANSACTIONS ON ENERGY CONVERSION 006. [3] Rekha T. Jagadui, Ghadi Radman, Modelg and contol of ditibuted geneation ytem cludg PEM fuel cell and ga tube, Electic Powe Sytem Reeach 77 (007) [4] A. Hajizadeh, M.A. Golka, A. Feliachi, POWER MANAGEMENT STRATEGY OF A HYBRID DISTRIBUTED GENERATION SYSTEM, Intenational Jounal of Ditibuted Enegy Reouce, Vol. 3, No., Apil-June 007. [5] M.A. Golka, A. Hajizadeh, Fuzzy-Baed Mitigation of Voltage Sag and Active Powe Contol Ditibution Sytem Ug Fuel Cell Ditibuted Geneation, Intenational Powe Sytem Confeence (PSC006), 3-5 Nov. 006, Tehan-Ian. [6] Yoon-Ho Kim, Sang-Sun Kim, An Electical Modelg and Fuzzy Logic Contol of a Fuel Cell Geneation Sytem, IEEE Tanaction on Enegy Conveion, Vol. 4, No., June 999. [7] J. Padull e, G. W. Ault, and J. R. McDonald, An tegated SOFC plant dynamic model fo powe ytem imulation, J. Powe Souce, pp , 000. [8] J.H. Lee, T.R. Lalk, and A.J. Appleby.: Modelg electochemical pefomance lage cale poton exchange membane fuel cell tack. Jounal of Powe Souce, 998, pp [9] Z. Yang, C. Shen, L. Zhang, M.L. Cow, and S.Atcitty, "Integation of a StatCom and Battey Enegy Stoage." IEEE Tanaction on Powe Sytem, Vol. 6, No., May 00, pp [0] Qian Ai, Yuguang Zhou, Weihua Xu, Adale and it application powe quality ditubance detection and fequency tackg, Electic Powe Sytem Reeach (006). [] T.K. Abdel-Galil, E.F. El-Saadany, M.M.A. Salama, Powe quality event detection ug adale, J. Elect. Powe Syt. Re. 64 () (003) [] Y. Zhu, K. Tomovic, «Development of model fo analyzg the load-pefomance of micotube and fuel cell», Electic Powe Sytem Reeach 6 (00) -. Am Hajizadeh He eceived hi B.S. degee Electical Engeeg fom Fedowi Univeity of Mahad, Ian 00, hi M.S degee Electical Engeeg fom the K.N. Tooi Univeity of Technology, Tehan, Ian 005, whee he i cuently puug hi Ph.D. degee. Hi cuent eeach teet clude telligent contol of ditibuted enegy eouce, optimization of hybid powe ytem, and ditibuted geneation. Maoud Aliakba Golka He wa bon Tehan, Ian 954. He eceived hi BSc degee fom Shaif Univeity of Technology, Tehan, Ian 977, hi MSc fom Oklahoma State Univeity, USA 979, and hi PhD degee fom the Impeial College of Science, Technology, and Medice (The Univeity of London, UK) 986, all Electical Engeeg (Powe Sytem). Hi employment expeience clude wokg a an Aociate Pofeo at The K.N. Tooi Univeity, Tehan, Advio to the Tehan Electicity Boad, and Head of Reeach at the Electic Powe Reeach Cente Tehan. Now he i an Aociate Pofeo at K.N. Tooi Univeity of Technology Tehan, Ian.