Distributed Renewable Energy under the Guidance of Price Autonomous Operation Technology

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1 Smar Grd and Renewable Energy, 2017, 8, hp:// ISSN Onlne: ISSN Prn: X Dsrbued Renewable Energy under he Gudance of Prce Auonomous Operaon Technology Arslan Habb 1*, Adeel Arshad 2, Rafq Khan 3 1 School of Auomaon, Norhwesern Polyechncal Unversy, X an, Chna 2 Fluds & Thermal Engneerng (FLUTE) Research Group, Unversy of Nongham, UK 3 School of Elecrcal Engneerng, X an Jaoong Unversy, X an, Chna How o ce hs paper: Habb, A., Arshad, A. and Khan, R. (2017) Dsrbued Renewable Energy under he Gudance of Prce Auonomous Operaon Technology. Smar Grd and Renewable Energy, 8, hps://do.org/ /sgre Receved: Augus 16, 2017 Acceped: Ocober 10, 2017 Publshed: Ocober 13, 2017 Copyrgh 2017 by auhors and Scenfc Research Publshng Inc. Ths work s lcensed under he Creave Commons Arbuon Inernaonal Lcense (CC BY 4.0). hp://creavecommons.org/lcenses/by/4.0/ Open Access Absrac Peneraon of Dsrbued Renewable Energy n acve dsrbuon nework has ncreased year by year, and he dsrbued characerscs of acve dsrbuon nework has become ncreasngly promnen; s dffcul for radonal cenralzed energy schedulng o solve he coordnaon of random oupu of dsrbued energy and he communcaon pressure of a large number of dsrbued daa. In hs paper, we propose a Dsrbued Renewable Energy Coordnaon Sraegy based on prce gudance, hrough herarchcal mul-agen model. The coordnaon model of each agen s nroduced n deal, regonal arge, prce coordnaon response sraegy and regonal secury consrans, usng Agen s Dsrbued Auonomy and Global Collaboraon o realze he Energy Balance of Acve Dsrbuon Nework and promoe he Sorage of Dsrbued Renewable Energy; he coordnaon sraegy focuses on he mpac of prce adjusmen on energy sorage and flexble load response capacy o mprove he dsrbued renewable energy consumpon. Fnally, hrough he quanave analyss of he comprehensve performance of he ndex, he evaluaon resuls of he radonal sequenal smulaon mehod are compared, and he raonaly and valdy of he proposed mehod are verfed. Keywords Evaluaon Index, Mul Agen, Dsrbued Renewable Energy, Prce Coordnaon 1. Inroducon In he recen years, he dsrbued generaon (DG) has been ncreased n acve DOI: /sgre Oc. 13, Smar Grd and Renewable Energy

2 dsrbuon nework and hs s because of rapd developmen of nermen renewable energy generaon represened by wnd and phoovolacs. Acve componen ypes and quanes have been ncreasng, so acve dsrbuon srucure s sll becomng more and more complex, and he dsrbued characerscs are becomng more promnen. The new requremens for he auonomy, operably and conrol of sysem have been pu forward [1]. A he same me, here are a large number of conrollable dsrbued resources n acve dsrbuon nework such as energy sorage, flexble load and so on. Energy sorage has he ably o ransfer power and energy; herefore, has become an effecve way o solve he problem of renewable energy access. The nroducon of energy sorage sysem (ESS) n acve dsrbuon nework can effecvely compensae for he problem of power sysem flucuaon caused by dsrbued renewable energy [2] [3] [4]. Flexble load s one of he mos promsng neracve resources n acve dsrbuon nework due o s nave and conrol capably. Makng he full use of flexble load can effecvely mprove he mpac of DG on dsrbuon nework and mprove he adopably of acve dsrbuon nework. I s dffcul o fully collec real me daa of DG, energy sorage and flexble load by he exsng daa acquson sysem n acve dsrbuon nework. A he same me, he oupu of Dsrbued Renewable Energy DG has obvous randomness and volaly. The coordnaed response of energy sorage and flexble load ge decenralzed, and he radonal cenralzed conrol mehod has slow communcaon. Therefore, because of he large amoun of calculaon, s dffcul o realze he coordnaed conrol of decenralzed and me-varyng acve dsrbuon nework sysem. The Mul-Agen Sysem (MAS) reles on s good auonomy, adapably and coordnaon, can mee he real-me neracon of dfferen sakeholders and adap o he developmen rend of he acve dsrbuon nework. Wh he dsrbued characerscs and auonomous decson, models of MAS have obvous advanages n solvng he coordnaon and opmzaon of complex acve power dsrbuon neworks [5]-[11]; he ref. [1] s based on ncreased acvy and dsrbuon of acve dsrbuon nework, n order o ncrease he ducly of acve dsrbuon nework, a mul agen conrol sysem for a new ype of dsrbuon nework s proposed. Ref. [11] ams a he problem of low accuracy and schedulng rsk of wnd power forecasng, and pus forward he use of energy sorage sysem (ESS) o mprove he scale of wnd power nework, and evaluae s economc performance from wo aspecs of ESS operaon benef and ncome. In he ref. [12], a mul-agen sysem (MAS) conrol model wh mul-class load response s consruced, whch s based on he characerscs of hgh densy of commercal users. The coordnaed conrol of he commercal load s carred ou wh he goal of user s comfor; he dsrbued conrol of flexble load such as elecrc vehcle, ar condoner and waer heaer s dscussed, whch provdes he bass for coordnaed conrol of acve dsrbuon nework. In Ref. [13] based on MAS, a dsrbued energy opmzaon model for acve dsrbuon neworks, and conrol srucure for regonal DOI: /sgre Smar Grd and Renewable Energy

3 auonomy and global coordnaon s proposed. The conrol sraegy s suded from he global mproved objecve of he dsrbued energy and he acve dsrbuon nework, he valdy of he dsrbued conrol sysem o he acve dsrbuon nework s proved, whch mproves he versaly and robusness of he sysem opmzaon model. Therefore, based on he acve dsrbuon nework secury consrans, he marke prce gude, coordnaon of DG, energy sorage and load and oher benefs are mporan means o promoe he ulzaon rae of Dsrbued Renewable Energy. Based on he herarchcal conrol srucure of MAS, hs paper proposes a dsrbued renewable energy coordnaon sraegy based on prce gudance and MAS regonal agen arge and acve dsrbuon nework. I provdes an effecve mehod for he coordnaon of Dsrbued Renewable Energy consumpon. Fnally, he comprehensve performance of he proposed conrol sraegy s evaluaed by usng he runnng ndex, and he valdy of he MAS conrol model s verfed by comparng he resuls of he radonal conrol mehod. 2. MAS Herarchcal Conrol Framework Desgn 2.1. MAS Srucure MAS s a knd of arfcal nellgence compung mehod; s ndependen characerscs make possble for elecronc devces wh common or conflcng goals o coexs n complex power sysems. MAS based on JADE plaform for Agen nformaon neracve, dsrbued smulaon based on JADE smulaon plaform has become an mporan research drecon n recen years. JADE s o follow he FIPA specfcaon, o acheve neroperably beween Agens, whle smplfyng he process of MAS developng plaform, Agen s he mddleware o help Agen o acheve message encodng, message ransmsson, message resoluon and message parsng work [4]. In hs paper, he characerscs of MAS communcaon and decson ordnance are adoped. A mul-agen srucure for coordnaed conrol of DG, ESS and flexble loads n an acve dsrbuon nework s proposed. The conrol srucure s shown n Fgure 1. The MAS herarchcal srucure of mul-agen model s used o conrol he DG, energy sorage and load, and he herarchcal mul-agen model s shown n Fgure 2. 1) Lead Agen (DNO): Sarng from he global arge, coordnang regonal agens, seng up he regonal caalyc sgnal o acheve he overall goal maxmzaon; 2) Regon Agen (DG, ESS, FL): In response o he drvng sgnal of he Agen, he regonal auonomy s realzed accordng o he regonal arge; 3) Conrolled Agen: To acheve he DG, energy sorage devces, flexble load conrol, response o he regonal Agen nsrucons MAS Coordnaon Process Tradonal me seres smulaon belongs o a smple se of power flow calculaon DOI: /sgre Smar Grd and Renewable Energy

4 Load DNO Load ~ DG (Mcro gas urbne) Flexble load WT ~ Flexble load Power lne (ESS) Load Load ES ES Communcaon Lne Load Fgure 1. Mul-agen conrol srucure n acve dsrbuon nework. Dsrbuon nework DNO-Agen Regonal DG-Agen Regonal ESS-Agen Regonal FL-Agen DG1 DG2 DGn ESS1 ESS2 ESSn Load1 Load2 Loadn Fgure 2. MAS herarchcal mul-agen model. a each me pon; herefore, s dffcul o use he radonal sequenal smulaon mehod o hghlgh he nave of DG and energy sorage n acve dsrbuon nework, a he same me, s dffcul o reflec he neracon beween DG, ESS and flexble load. Compared wh he radonal conrol mehods, he decenralzed decson makng of MAS ncreases he uncerany of he acve dsrbuon sysem operaon, a he same me, he operaon sae of he sysem s opmzed by he muual nfluence and adjusmen sklls beween DG, energy sorage and flexble load. Ths paper focused on DG n acve dsrbuon nework, he coordnaed conrol of energy sorage and load s pu forward, and he scheme of nensve opmzaon and decenralzed conrol for MAS s proposed; DNO-Agen s manly responsble for coordnang he power balance of he whole dsrbuon nework sysem, he conrolled equpmen n he regonal Agen coordnaon area s adaped o he DNO opmzaon objecve. The coordnaon process s DOI: /sgre Smar Grd and Renewable Energy

5 shown n Fgure 3. DNO send elecrcy prce and dsrbuon nework nformaon o regonal Agen, regonal Agen acheves coordnaed response and feedback response scheme accordng o regonal auonomy goal, DNO collec regonal response plan, check sysem secury, and make plans o feedback area Agen; When he zone agen naes an acve reques o DNO, DNO coordnaes he oher regonal agens o develop he scheme ha mplemens he response o he regonal agen reques n case of sysem secury. 3. Prce Based Mul Agen Coordnaon Sraegy 3.1. DNO-Agen Model DNO-Agen s responsble for monorng and mananng he power balance and sysem power flow safey of he whole dsrbuon nework sysem. DNO send elecrcy prce and dsrbuon nework nformaon o regonal Agen; Based on ensurng of overall supply, demand balance, safe and sable operaon of he acve dsrbuon nework, DNO receve a reques from he area Agen or provde a response plan. DNO ams a mnmzng coordnaon coss. DG-Agen sends prce and oupu power requess based on crcumsances whn he regon DNO-Agen sends he elecrcy prce and dsrbuon nework relaed nformaon o regon Agen ESS-Agen selecs he work model based on he prce and he SOC saus The regon Agen selecs he operaon mode based on he receved nformaon and he saus whn regon FL-Agen provdes he response accordng o he elecrcy prce and he regonal load conrol saus Yes Send response scheme Regonal secury consrans DNO-Agen No Deny response No Yes Sysem power flow calbraon Denal of response Feedback regonal Agen ransacon plan; ransmsson prce and dsrbuon nework relaed nformaon Fgure 3. MAS coordnae conrol. DOI: /sgre Smar Grd and Renewable Energy

6 mn f = CP grd, + CP DG, + CP L, + CP ES, P + P = P + P (1) grd, DG, L, ES, Type: C s he prce of me; P grd, s he power generaon of he grd; P DG, s he DG response; P L, s he load response; P ES, s he energy sorage response, he charge s posve, and he dscharge s negave. Sysem secury consrans are as follows: 1) Acve power and reacve power flow consran Type: P and he oal number of nodes; G j and N ( θ θ ) P V V G cos + B sn = 0 j j j j j j= 1 N ( θ θ ) Q V V G sn + B cos = 0 j j j j j j= 1 Q respecvely for he node, acve and reacve power; N s V s he node volage; V j s he j node volage; B are j lne conducance and elecrcal accepance, respecvely. j 2) Node volage consrans Type:,mn,,max,mn,max (2) V V V (3) V V are node volage lower and upper lm, respecvely. 3) Branch power consrans P P (4) l,max Type: P l,max s he upper lm of he ransmsson power of lne L Regonal Agen Model DG-Agen DG-Agen acheves acve response o DG energy managemen and acve dsrbuon nework demand hrough coordnaed conrol of dsrbued generaon uns n acve dsrbuon nework. Dsrbued generaon ncludes conrollable power generaon and unconrollable power generaon, n whch unconrolled power generaon manly refers o dsrbued renewable energy power generaon. In he DG model, a conrollable mcro gas urbne and an unconrollable fan generaor are aken as examples. The wnd urbne s oupu model smulaes s oupu by usng Mone Carlo and wo-parameer Webull, oupu power s 0 V < V, V > V V V c P, = R Vc < V < Vs Vs Vc R Vs < V < Vf c f where: P, s he oupu power of he frs wnd urbne a ; V he wnd speed for he momen; V c s he cu n wnd speed; V f s he cu ou wnd speed; V s he raed wnd speed; R s he raed capacy of he frs wnd urbne. s (5) DOI: /sgre Smar Grd and Renewable Energy

7 The mcro urbne mees he power consran: P < P < P (6) MT,mn MT, MT,max where: P MT,mn s he mnmum oupu power of he gas urbne; P MT, are he acual oupu power of he gas urbne a, and P MT,max Maxmum oupu power for gas urbne. DG-Agen collecs and manages he oupu saus nformaon of he gas urbnes and wnd urbne n he area, and ensures he safe operaon of all he equpmen n he Agen. Among hem; he wnd urbne oupu s no conrollable, Agen should be conrolled o maxmze s absorpve capacy as he goal; he oupu of he gas urbne s conrollable, whch s manly used o mee he demand of he wnd urbne and he sored energy when he oupu power s no enough. The DG-Agen coordnaed conrol funcon s shown n Fgure 4. A he nal momen, DNO sends he grd prce and sysem load demand o DG-Agen, DG-Agen collecs he power generaon saus and oupu power of conrolled DG, Feedback o DNO for s own responsveness; DNO akes he sysem power balance as he consran, coordnaes he Agen response of each regon, deermnes he purchasng power and feedback DG-Agen; DG-Agen accep he remanng amoun of dsrbuon power of wnd machne for calculang purchasng power, maxmzes he mplemenaon of renewable energy generaon n he regon, smulae he acve dsrbuon nework sorage and load response effors. Accordng o he remanng power of wnd urbnes, DG-Agen adjus he prce of elecrcy, Inae he consumpve reques o DNO; DNO coordnaes oher regonal Agen o mee he demand response of DG-Agen, and feedback he coordnaon purchase plan o DG-Agen. The DG-Agen acceps he response scheme, and f he renewable energy s lef whn he secury consran, he consumer reques s naed agan. I s worh emphaszng ha, The DG-Agen coordnaon sraegy s based on he remanng power and marke prce of he wnd urbne, whch smulaes he DG-Agen 1. Collec he power generaon and power generaon saus of DG n hs area 2. Receve he purchase plan, he dsrbuon of wnd power machne calculaon of resdual power; adjus he prce accordng o he amoun of resdual, nae consumpve reques 3. The clean energy surplus n he area repeas sep 2, and on he conrary, he round ends wh coordnaon. Fgure 4. Coordnaon conrol of DG-Agen. Grd prce Oupu Power Purchase plan Tarff adjusmen Purchase plan DNO-Agen 1. Transmsson prce and load demand 2. Coordnae he Agen response; deermne he DG power generaon, and feedback 3. Recevng DG-Agen requess o oher regonal consumpve, Agen response, feedback and coordnaon scheme DOI: /sgre Smar Grd and Renewable Energy

8 energy sorage and flexble load n he acve dsrbuon nework o mprove s consumpon. When he wnd urbne oupu surplus, he DG-Agen acvely sends a power reques o he DNO, he ransmsson of nformaon ncludng wnd urbne power generaon, he remanng adjused prce, he prce adjusmen s as follows: p Cgrd 1, p = P 10P p P CWT = kc1cgrd 1, < p < P 10P 2 p P kc2cgrd 1,0< p 10P 2 where: C WT s wnd power prce; C grd s power grd arff; k c1 and k c2 are prce adjusmen facors; P s oal power wnd urbne for of me; p s resdual or remanng power of wnd urbne for me. (7) ESS-Agen ESS-Agen collecs and manages he saus nformaon of he energy sorage devces n he regon, and coordnaes he demand of he acve dsrbuon nework on he bass of ensurng he safe operaon of he energy sorage, maxmze he consumpon of wnd urbne power. Energy managemen s realzed n he ESS-Agen o maxmze he energy sorage revenue n he area. Energy sorage devces are generally lmed by he capacy and sorage charge saus, and o exend lfe of he energy sorage devce n he sysem, overcharge and over dscharge s no allowed. The sae funcon s SOC, + 1 = SOC, + ηchpch,, ηdspds,, (8) Resrcons: 0 Pch,, Pch,,max 0 Pds,, Pds,,max SOC SOC SOC,mn,,max where: SOC, for sorage devce a sae of charge (SOC); P ch,, and P ds,, respecvely n devce me chargng and dschargng power of he sorage; η ch and η ds he charge and dscharge effcency; P ch,,max and P ds,,max he charge and dscharge power sorage devce; for he duraon of he curren sae; SOC,mn and SOC,max are he mnmum and maxmum allowable energy sorage devces, Maxmum charge sae. A he nal momen, DNO sends he power grd prce o he ESS-Agen. Whn he scope of secury consrans, ESS-Agen deermnes he energy sorage, dscharge saus and capacy of he sored energy accordng o he sae of he energy sorage devce n he regon and he prce of he power grd, and feedback s response o he DNO; when DG-Agen nae he launch reques o DNO, DNO sends he wnd power adjusmen prce and he remanng power (9) DOI: /sgre Smar Grd and Renewable Energy

9 generaon o he ESS-Agen; ESS-Agen deermnes he sorage sae and power of sored energy accordng o he sae of energy sorage and he prce of wnd energy. In he ESS-Agen regonal conrol sraegy, he charge and dscharge behavor of he energy sorage devce s guded by he sae of sorage energy and he prce of elecrcy, he am of maxmzng consumpon of wnd power and ncreasng s own ncome. The workng sae of he energy sorage n he perod s deermned by consderng he dfference of he elecrcy prce n dfferen perods and he SOC sae of he energy sorage devce n he curren perod, and he selecon of he workng sraegy s shown n Table 1. ESS-Agen prce based on DNO and nformaon of acve dsrbuon nework, combned wh he sae of energy sorage o choose her own workng sae, a he peak load, he coordnaed energy sorage dscharge can no only allevae he sysem power supply pressure, bu also maxmze he energy sorage benefs; When he load s low, he energy sorage and chargng s coordnaed, whch realzes he consumpon of renewable energy, reduces he peak and valley load dfference of he acve dsrbuon sysem, and reduces he chargng cos. Ths sraegy ensures safe operaon of sored energy n he regon, and based on ncome, mprove he ably of he consumpve Dsrbued Renewable energy FL (Flexble Load) Agen The behavor of flexble load s nfluenced by user s preferences and envronmenal facors. I has srong conrollably and s easly guded by elecrcy prce and oher envronmenal facors; hrough he coordnaon of flexble load conrol can realze he acve power dsrbuon sysem peak, and conrbue o he consumpve renewable energy oupu. FL-Agen collecs and manages he saus nformaon of he flexble load n he area, n order o ensure he comfor of he users; he sysem conrols he flexble load o respond o he DNO demand. A he nal me, he DNO sends Table 1. Conrol of energy sorage. Tme perod Elecrcy prce Energy sorage SOC Energy sorage saus Valley/low me Grd prce 0.2 SOC < 0.5 Normal chargng = Grd prce 0.5 SOC < 0.85 Low power chargng = Wnd energy prce adjusmen 0.2 < SOC < 0.5 Lm charge 0.5 SOC < 0.85 Normal chargng Usual me Grd prce / Sop workng = Peak me = Wnd energy prce adjusmen Grd prce Wnd energy prce adjusmen 0.2 SOC < 0.5 Normal chargng 0.5 SOC < 0.85 Lm dscharge 0.2 SOC < 0.5 Normal dscharge / Sop workng DOI: /sgre Smar Grd and Renewable Energy

10 he power grd prce o he FL-Agen, and he FL-Agen sends he response o he DNO accordng o he load demand n he area; When DG-Agen launched he consumpve requess o DNO, DNO send he wnd power arff adjusmen and surplus generaon o FL-Agen; FL-Agen responds he load response accordng o he sae of he flexble loads and he safey consrans n he area. The response model of he flexble load n he model s P C C = ε P (10) C L, Load, C T = P T Load, P C Load, (11) where: P L, are he response quanes of flexble loads a momens; P Load, s he oal amoun of flexble load n FL-Agen a me ; ε s he overall prce elascy coeffcen of he flexble load; C for he comprehensve prce; T s he whole work cycle; C s he curren grd prce Prce Based Inerregonal Coordnaon When he acve energy dsrbuon nework requess canno be acheved whn he DG Agen area dsrbued renewable energy consumpon, he DG-Agen neracs wh he DNO-Agen hrough he proocol mechansm o acheve he neracve proocol o realze he consumpon of regonal dsrbued renewable energy. There are wo dffcules n he sorage of renewable energy: 1) Hard mode: regonal renewable energy consumpve s dffcul, acve dsrbuon nework energy coordnaon of renewable energy power surplus for p 0.5P. In order o acheve he dsrbued renewable energy consumpon, reduce he abandoned wnd, renewable energy should seek new response o he consumpve surplus. In he dffcul mode, he amoun of renewable energy power generaon s large, Negave energy sorage n he sysem, Flexble load agan respond o he pressure of large consumpon, DG-Agen sgnfcanly reduce he elecrcy prce, The prce adjusmen Formula (7), hope o lower prces o smulae and mprove he sysem response effors o promoe renewable energy consumpon. 2) Easy mode: regonal renewable energy consumpve s easy, acve dsrbuon nework energy coordnaon of renewable energy power surplus for p < 0.5P. In an easy way, renewable energy generaes less power, he pressure of load and energy sorage s less, and DG-Agen reduces he prce of elecrcy properly. The prce adjusmen s shown n ype (7), n he promoon of renewable energy consumpon whle ensurng he economc benefs of DG agens. When renewables generae elecrcy, he DG-Agen adjuss he elecrcy prce, DNO-Agen requess power consumpon; DNO-Agen sends a reques for renewable energy o oher regonal agens; ESS-Agen deermnes he workng sae of he energy sorage accordng o he elecrcy prce and he charged sae of he sored energy n he regon; FL-Agen deermnes he response of he re- DOI: /sgre Smar Grd and Renewable Energy

11 gonal load accordng o he change of elecrcy prce; DNO receves he energy sorage charge and he load response feedback, Check sysem flow, If he secury reurns DNO-Agen accommodaon scheme, On he conrary, he DG-Agen refused o accep he reques, requrng he wnd. 4. Operaonal Level Evaluaon Operaonal level evaluaon ncludes performance evaluaon of acve dsrbuon nework n erms of operang volage level, sysem load and componen economy. The comparson and analyss of dfferen conrol mehods no only need o compare wh he ndex, bu also analyze he whole performance. However, he dmenson and naure of he evaluaon ndexes of acve dsrbuon nework are dfferen, and no all he ndexes can be analyzed drecly. Fuzzy Herarchy Process, FAHP o acheve he complex mul-facor co-scale analyss, he subjecve nfluence of he decson maker s even lower Fuzzy Comprehensve Analyss FAHP s a combnaon of quanave and qualave analyss, and s suable for mul-objecve decson-makng, I can analyze he non-sequenal relaons among mulple objecves, and avod he bas caused by he subjecve lmaons of he analyc herarchy process; esablshes he fuzzy conssency judgmen marx hrough he comparson of he nfluencng facors, he non-correlaon qualave relaon beween he ndexes of dsrbuon nework s changed no quanave wegh relaon, and reduce he nfluence of subjecve defnon wegh value on he analyss resul. In hs paper, a fuzzy conssen judgmen marx s esablshed by comparng he 22 of he nfluencng facors [13], Quanave converson values for qualave relaonshps beween ndcaors are shown n Table 2. The wegh value of he ndex s calculaed by usng relaon scale beween ndexes ω = M r j= 1 j 1 M M r M = 1 j= 1 j (12) Table 2. Relaonshps beween elemens. Scalng r Defnon Descrpon (compared he wo elemens) 0.5 Equally mporan Equally mporan 0.6 Slghly mporan An elemen s a lle more mporan han anoher 0.7 Obvously mporan One elemen s more mporan han anoher 0.8 very mporan One elemen s very mporan han anoher elemen 0.9 Exremely mporan One elemen s more mporan han he oher 0.1, 0.2, 0.3, 0.4 Inverse comparson If he elemen a, a s compared o j r j, Then he elemen a, a s compared o r = 1 r j j j DOI: /sgre Smar Grd and Renewable Energy

12 where: ω s he ndex wegh value; M s he oal number of evaluaon ndexes; r s he scalng relaon beween wo ndexes. j Conver all ndex resuls o non-dmensonal and mpacful values. The comprehensve evaluaon score of he operaon sraegy s obaned by usng he wegh coeffcen and he effecve value of he ndex, he formula s M = 1 S = 100 ω X (13) where: V Var volage varance; Z j lne mpedance; Q lne j ermnal reacve load; V lne j frs ermnal volage; X j Lne j Reacance; n Number of load nodes; D( ) Sysem node load value; b ( ) Sored energy oupu power; K Energy consumpve capacy; m Toal energy sorage devce; L Toal load rough; P, DG, Wnd energy charge; B 1 Energy arbrage gans; Cch,, C ds, Charge (dscharge prce); Pds,, P ch, Charge (dscharge power) Volage Operang Level Volage operang level ncludes sysem volage devaon, Reacve sably. I s he man ndex o measure he qualy of he power supply of he mul ype energy n he acve dsrbuon nework. The guaranee volage excurson s he basc ask of acve power dsrbuon sysem operaon adjusmen [14]. The uncerany of clean energy oupu and load flucuaon exacerbaes he flucuaon of grd volage largely [15]. In acual operaon, adjusmen of operang mode, DG and load mng flucuaons wll lead o node volage offse, he volage devaon has a negave effec on he equpmen n he sysem. In addon, he reacve load wll also affec he sably of he sysem volage, and s change wll lead o sudden abrup change n volage Operang Peak Valley Dfference The nroducon of renewable energy no he acve dsrbuon nework s a problem ha he power sysem has been ryng o solve. The effecve conrol of energy sorage and load n acve dsrbuon nework can reduce he negave Table 3. Evaluaon ndcaors. Index Formula Sgnfcance N N Volage 1 1 V = 2 Var V V devaon N = 1 N j= 1 Reflec he degree of flucuaon of node volage Reacve power sably 2 4ZQ j j VSI = VX j Measurng sysem reacve sably n N n = 1 n j= 1 Load ransfer f= D ( ) + b ( ) D( j) + b( j) Energy sorage benefs Wnd energy consumpon K m L = 1 = m = 1 P R, DG, B = C P C P 1 ds, ds, ch, ch, T T Measure he smoohness of a load curve When he low load can reflec he absorpve capacy of he energy sorage devce Evaluae he economy of he energy sorage sysem DOI: /sgre Smar Grd and Renewable Energy

13 mpac of nermen energy and promoe he permeably of dsrbued renewable energy n power grd. On he oher hand, he sysem can effecvely adjus he peak and valley load dfference, and allevae he power supply pressure a he peak load of he dsrbuon nework. Clampng peak fllng s an mporan ask of acve dsrbuon nework opmzaon, whch s an mporan ndex o measure he sably and relably of dsrbuon nework. Peak dayme load, The energy sorage dscharge can effecvely allevae he load generaon pressure on he generaor and avod he full load operaon of he generaor whle reducng he sysem load sheddng rae; When he ngh load s low, he randomness of wnd power generaon and he capacy of he sysem load are reduced. When he ngh load s low, he randomness of wnd power generaon and he reduced capacy of he sysem load are caused by he wnd blows. The energy sorage charge plays he role of load, whch consumes excess wnd energy and mproves he ulzaon rae of wnd energy, and for he dayme load peak energy sorage dscharge energy savngs. For he power sysem, reducng he peak load dfference can effecvely delay he upgradng of power equpmen capacy, mprove equpmen ulzaon, and reduce sysem cos. Furhermore, evaluaon ndexes and s sgnfcances are shown n Table Energy Sorage Arbrage Because of he randomness and volaly of renewable energy sources, he presence of ESS s essenal; he nroducon of energy sorage n acve dsrbuon nework can ncrease he ulzaon rae of renewable energy and smooh load curve, and s an effecve means o adjus he volage and frequency of he sysem [16]. The hgh cos lms he large-scale applcaon of energy sorage n dsrbuon nework, and he maxmzaon of prof wh lmed capacy s he goal of energy managemen opmzaon of acve dsrbuon nework. I s also an mporan ndex o evaluae he energy sorage economy sysemacally. 5. Case Sudy 5.1. Smulaon Condon In hs paper, an acve dsrbuon nework sysem wh IEEE33 nodes s used. The valdy and effecveness of mul-agen operaon conrol model and sraegy for acve power dsrbuon nework are analyzed and verfed, he srucure of he acve dsrbuon nework s shown n Fgure 5, and he nsallaon nformaon of DG and energy sorage s shown n Table 4. In order o prolong he servce lfe of he energy sorage devce, se SOC,mn = 0.2, SOC,max = 0.85, The nal sae of sored energy s SOC,0 = Smulaon of Coordnaed Conrol Based on MAS In hs paper, he peak prce s adoped as he example, and he elecrcy prce s shown n Table 5. In he model, DG, energy sorage and load are based on he prce o gude he formulaon of Agen coordnaed conrol sraegy. DOI: /sgre Smar Grd and Renewable Energy

14 Fgure 5. Acve dsrbuon nework (AND) srucure. Table 4. The nsallaon nformaon of DG and ES. Insallaon node Insallaon ype Capacy/MW 14 Mcro Gas Turbne WT ES ES 0.1 Table 5. Elecrcy prce of grd, kwh. Valley Peaceme Peak me 06:00 ~ 07:00 08:00 ~ 14:00 23:00 ~ 05:00 15:00 ~ 19:00 20:00 ~ 22: The smulaon process of herarchcal conrol model for acve dsrbuon nework s as follows: A he begnnng of each perod, he DNO-Agen naes he reques behavor n he MAS sysem and sends he prce and he dsrbuon nework demand o he JADE servce plaform; DG-Agen collecs he avalable elecrcy of he wnd generaor n he area, and makes he bddng sraegy accordng o he elecrcy prce and he elecrcy quany, and feedback o servce plaform, and afer he end of he sngle round bddng sale, f he remanng power, accordng o he remanng amoun of elecrcy o modfy he quoaon, re apply o he DNO, o develop a new round of plans; ESS-Agen collecs he saus nformaon of all he energy sorage n he regon, and develops he bddng scheme accordng o he curren prce and he energy sorage sae; FL Agen responds o he marke prce and he oal conrollable load a ha me. The specfc coordnaon process s shown n Fgure 6. I s worh emphaszng ha, despe he adjused schedule, DNO-Agen calculaon s generaed, and he sysem power flow secury check s also generaed by DNO, However, hs s based on he operaon daa, daa and coordnaon scheme provded by Agen n dfferen regons. Compared wh he cenralzed DOI: /sgre Smar Grd and Renewable Energy

15 Fgure 6. Realzaon of coordnaed conrol for acve dsrbuon nework. conrol, he cenralzed o decenralzed model adoped n hs paper can dsperse he complex opmzaon process, a he same me, he processng speed of he sysem s faser and he operaon dffculy s reduced Tradonal Operaon Model In radonal operaon model, he nsallaon node, capacy and elecrovalence of DG and energy sorage, he wnd urbne oupu model and he nal energy sorage sae are conssen wh he model proposed n hs paper. Each me perod, he wnd urbne and he mcro gas urbne delver he power generaon o he dsrbuon nework, hen he dsrbuon nework mus force s oupu, DG oupu and consumpon whou prce adjusmen; he energy sorage workng sae s relaed o he curren sorage energy, SOC and he power grd prce, bu sored energy can only be operaed a one me. The oupu of dsrbued renewable energy sources does no have acve regulaon capably; n addon, he sysem does no have a flexble load under acve managemen Resuls and Analyss The load peak and valley dfference of he acve dsrbuon nework sysem leads o he ncrease of he nvesmen cos and he decrease of he operaon DOI: /sgre Smar Grd and Renewable Energy

16 safey and sably. As can be seen from Fgure 7, he peak load dfference of he dsrbuon sysem s abou 9.57 MW n he radonal model, he sysem load peak and valley dfference of he MAS conrol model menoned n hs paper s only 7.4 MW, compared o he radonal model of he peak load s reduced by 22%, herefore, hs paper proposed a dsrbued conrol sraegy s effecve n regulang he sysem load han he radonal conrol sraegy. Fgure 8 s he energy sorage based on he ESS-Agen conrol model chargng and dschargng behavor and energy prce, as can be seen from he dagram, he sellng prce of he wnd power s dfferen from he prce of he power grd Fgure 7. Sysemac load comparson of dfferen conrol measures. Fgure 8. Energy sorage coordnaon process n MAS. DOI: /sgre Smar Grd and Renewable Energy

17 a dfferen mes, When he power grd s a peak me, he wnd urbne oupu s large, he energy sorage dscharge s flexble and he load response s flexble. In order o mprove he amoun of wnd energy consumpon, wnd energy prces and grd prce dfference as hgh as 0.03 US$/kWh; When he power grd s n he valley, he elecrcy prce, A he same me, consumpon of energy sorage and load, he prce dfference beween wnd energy and power grd s only 0.01 US$/kWh; Compared o he sorage and dscharge sae of sngle energy sorage cenralzed conrol, shown n Fgure 9, MAS model of energy sorage n power grd and elecrcy by wnd power s composed of wo pars, drecly reflecs he sorage of renewable energy consumpon. In addon, he conrol sraegy adoped n hs paper ncreases he uncerany of energy sorage behavor, and fully explores he acve decson-makng ably of ESS-Agen o energy sorage behavor, makes he prce guded ESS-Agen decson model more economcal. In hs paper, he relaonshp beween he elemen scale and he ndex wegh s shown n Table 6. The operaon performance of he dsrbuon nework under wo conrol modes s evaluaed by usng he evaluaon ndex, and he resuls are shown n Table 7. As can be seen from Table 6, he volage operaon level accouns for he larges value of he wegh, and he economc value of he wegh s he smalles, whch conforms o he basc requremens of he safe operaon of he power sysem. Table 7, he load ransfer ndex based on MAS coordnaon s only 15.2% of he radonal conrol model. I shows ha he dsrbued conrol mehod has a sgnfcan effec on sablzng he load flucuaon, and can effecvely smooh he load curve; In addon, he volage devaon ndex s 41.7% of he radonal conrol model, and he proposed mehod s more effecve n conrollng he Fgure 9. Energy sorage coordnaon process of radonal model. DOI: /sgre Smar Grd and Renewable Energy

18 Table 6. Relaonshp beween evaluaon ndexes and ndex wegh. Volage level Peak load dfference Economy of energy sorage Volage Load Economc effcency Wegh value Table 7. Index analyss of dfferen conrol modes. Quanave ndex MAS model Tradonal model Volage devaon (max) Reacve power sably (max) Load ransfer (max) Wnd energy consumpon 0.35 / Energy sorage arbrage/us$ Compose score (100 Pon sysem) node volage of acve dsrbuon nework, and can effecvely adjus he dsrbued DG, The adverse effecs of load flucuaon on volage mprove he sably and power qualy of acve dsrbuon nework; From he sably ndex, he ndex values of all he nodes n he wo models are sable a abou 0.7, However, hs sraegy canno mprove he reacve power sably n he sysem. The nroducon of energy sorage has promoed he rapd developmen of mul ype power generaon n acve dsrbuon nework, and he core of energy sorage coordnaon conrol s o explore he sorage capacy and mprove he sorage economy. The comparson of energy sorage arbrage values from Fgure 8 and wo conrol mehods s based on he ESS-Agen energy sorage conrol sraegy, he energy sorage sysem s annual revenue was 14% hgher han he radonal model, we can see ha he economy of he MAS model of energy sorage n hgher; The model presened n hs paper can clearly monor he acual workng sae and energy sources of energy sorage devces, and reflec he promoon of energy sorage o mprove he permeably of Dsrbued Renewable Energy sources. In addon, he use of Fuzzy Analycal Herarchy Process (FAHP) o calculae he comprehensve score of wo models, pons hgher han he radonal MAS model, s proved ha he proposed conrol sraegy of MAS based on acve dsrbuon nework operaon conrol s beer han he radonal model conrol sraegy. 6. Concluson In hs paper, a prce gudance coordnaon conrol sraegy based on MAS s proposed. Consderng he oupu characerscs of DG and he response cha- DOI: /sgre Smar Grd and Renewable Energy

19 racerscs of energy sorage and load, a regonal mul-agen model s esablshed, and he energy managemen opmzaon of acve dsrbuon nework s realzed under he marke mechansm; Furhermore, he performance of acve dsrbuon nework s analyzed by usng ndex. Compared o he radonal cenralzed conrol mehod, hs model uses mul-agen nformaon exchange characerscs, and ncreases he acve dsrbuon nework operaon uncerany, makng he smulaon run process closer o he acual sae; a he same me, he prce facor s used o gude he coordnaon of he energy n he acve dsrbuon nework, whch hghlghs he acve response capably of he energy sorage and load, and ncreases he cooperaon beween he componens. In addon, he evaluaon ndexes quanfy he dfference beween he dsrbued conrol mehod and he radonal cenralzed conrol mehod, and provdes a ran of hough for he subsequen research o choose he mers of dfferen plannng schemes. References [1] Prosejovsky, A., Merdan, M. and Scher, G. (2013) Demonsraon of a Mul-Agen-Based Conrol Sysem for Acve Elecrc Power Dsrbuon Grds. IEEE Inernaonal Workshop on Inellgen Energy Sysems, 14 November [2] Sh, T., Zhang, B., Chao, Q., e al. (2016) Economc Sorage Rao and Opmal Conrol of Hybrd Energy Capacy Combnng Sablzed Wnd Power Flucuaons wh Compensaed Predcve errors. Power Sysem Technology, 40, [3] Awa, Y.M. and El-Saadany, E.F. (2000) Opmal Allocaon of ESS n Dsrbuon Sysems wh a Hgh Peneraon of Wnd Energy. IEEE Transacon on Power Sysem, 25, hps://do.org/ /tpwrs [4] Yan, G., Lu, J., Cu, Y., e al. (2013) Economc Evaluaon of Improvng he Wnd Power Schedulng Scale by Energy Sorage Sysem. Proceedngs of he CSEE, 33, [5] Logenhran, T., Srnvasan, D., Khambadkone, A.M., e al. (2012) Mul Agen Sysem for Real-Tme Operaon of Amcrogrd n Real-Tme Dgal Smulaor. IEEE Trans Smar Grd, 3, hps://do.org/ /tsg [6] L, J., Song, X. and Meng, X. (2015) Herarchcal Conrol Model of Smar Dsrbuon Nework Based on Self-Organzng Mul-Agen Sysem. In: Inernaonal Conference on Renewable Power Generaon, Norh Chna Elecrc Power Unversy Press, Bejng, 1-6. [7] Bellfemne, F., Pogg, A. and Rmassa, G. (1999) JADE A FIPA-Complan Agen Framework. C Sel Inernal, 31, [8] Dmeas, A.L. and Hazargyrou, N.D. (2005) Operaon of a Mul Agen Sysem for M Crogrd Conrol. IEEE Transacons on Power Sysems, 20, hps://do.org/ /tpwrs [9] Jang, R., Qu, X. and L, D. (2014) Mul-Agen Sysem Based Dynamc Game Model of Smar Dsrbuon Nework Conanng Mul-Mcrogrd. Power Sysem Technology, 38, [10] Hao, Y., Wu, Z., Dou, X., e al. (2012) Applcaon of Mul-Agen Sysems o he DC Mcrogrd Sably Conrol. Proceedngs of he CSEE, 32, [11] Yuan, T., Chen, J., Lu, P., e al. (2014) Sraegy of Improvng Large-Scale Wnd DOI: /sgre Smar Grd and Renewable Energy

20 Farm Oupu Flucuaon Based on Energy Sorage Sysem. Power Sysem Proecon and Conrol, 42, [12] Yu, N., Yu, L. and L, G. (2015) Conrollable Load Managemen Sraegy for Commercal Users Based on Mul-Agen n Smar Grd Envronmen. Auomaon of Elecrc Power Sysems, 39, [13] Pu, T., Lu, K., L, Y., e al. (2015) Mul-Agen Sysem Based Smulaon Verfcaon for Auonomy-Cooperave Opmzaon Conrol on Acve Dsrbuon Nework. Proceedngs of he CSEE, 35, [14] Lan, J., Xu, Y., Huo, L., e al. (2006) Research on he Prores of Fuzzy Analycal Herarchy Process. Sysems Engneerng-Theory & Pracce, No. 9, [15] Chen, F., Lu, D. and Chen, Y. (2015) Herarchcally Dsrbued Volage Conrol Sraegy for Acve Dsrbuon Nework. Auomaon of Elecrc Power Sysems, 39, [16] Wang, C., Sun, W., Y, T., e al. (2013) Revew on Energy Sorage Applcaon Plannng and Benef Evaluaon Mehods n Smar Grd. Proceedngs of he CSEE, 33, DOI: /sgre Smar Grd and Renewable Energy