Modeling of Energy Management Systems for Commercial Parks with Thermodynamic Equipment

Transcription

1 IOP Conference Seres: Earh and Envronmenal Scence PAPER OPEN ACCESS Modelng of Energy Managemen Sysems for Commercal Parks wh Thermodynamc Equpmen To ce hs arcle: Sh Shanshan e al 2017 IOP Conf. Ser.: Earh Envron. Sc Relaed conen - Exper assessmen of he curren sae of he energy managemen sysem n he company Anna Mnnullna and Ras Abdrazakov - Tool eaches elecrcy conceps Solomon Fscher and Paul Gluck - Energy effcency monorng and economc analyss for energy savng poenal n UNITEN M Reyasudn Basr Khan Razal Jdn Jagadeesh Pasupule e al. Vew he arcle onlne for updaes and enhancemens. Ths conen was downloaded from IP address on 10/02/2018 a 11:29

2 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ Modelng of Energy Managemen Sysems for Commercal Parks wh Thermodynamc Equpmen Sh Shanshan 1 a Zhang Yu 1 b Fan Luyang 2 c and Luo Tan 2d 1 Sae Grd Shangha Elecrc Power Research Insue Chna 2 Shangha Jaoong Unversy Chna a shshsh@sh.sgcc.com.cn b zhangyu@sh.sgcc.com.cn c @qq.com d pans1993@qq.com.cn Absrac. Commercal park energy managemen sysems (CPEMS) can reasonably plan applances schedule of commercal enans (CT) and lower her elecrcy purchasng cos. However n he exsng models hermodynamc equpmen lke ar condoners and waer heaers are no precse enough falng o reflec he acual operang characerscs of he equpmen. Ths paper presens an energy managemen sysem model ncludng hermodynamc equpmen. By coordnang he elecrcy consumpon schedule of mulple CTs CPEMS can reduce CTs elecrcy purchase coss. In he demonsraon example elecrcy purchase coss of CTs are reduced and operaors of CPEMS gan prof provng he feasbly of he model. 1. Inroducon A commercal park (CP) has a funcon combnng eang accommodaon ransporaon shoppng and eneranmen. Wh he developmen of Chna's economy CPs elecrcy consumpon grow rapdly. On he one hand varous smar applances usually conrolled by smar devces lke smar phones are beng used gradually. On he oher hand wh he developmen of phoovolac and oher dsrbued power echnology ogeher wh cos reducon more and more dsrbued phoovolac power used by CTs (lke resaurans hoels ec.) apply for access o he grd[1]. The mporance of nellgen CP power consumpon and demand sde response echnology are arousng scholars aenon. In radonal power sysems user sde s usually deemed as a smple power consumer. However afer he energy crss n he 1970s Europe and he Uned Saes launched a varey of elecrcy prce sysems and began a research abou demand sde managemen (DSM)[2-5]. As he power demand grows many scholars sar o sudy energy managemen sysem (EMS)[6-10]. Through monorng and collecng users power consumng nformaon EMS can analyse users consumpon habs and add overall managemen and opmzaon o her power consumpon. A user s load opmzaon model based on consumpon effcency was proposed n [6] whch analysed he nfluence of dfferen consumpon habs n he model. Under he background of day-ahead and real-me power markes a knd of mxed neger programmng algorhm was proposed n [7] whch focused on chargng modes of elecromoble wh energy sorng devces. The general model of EMS wh changng elecrcy prces s dscussed n [8] whch compares he effecs of solvng hgh-dmensonal opmzaon problems usng heursc algorhm and Q-learnng algorhm respecvely. The power s connuy and dscreeness ransferably and nransferably nerrupbly and non-nerrupbly of applances Conen from hs work may be used under he erms of he Creave Commons Arbuon 3.0 lcence. Any furher dsrbuon of hs work mus manan arbuon o he auhor(s) and he le of he work journal caon and DOI. Publshed under lcence by IOP Publshng Ld 1

3 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ are analysed n [10] whch suded he modelng and opmzaon of EMS ncludng applances such as PVs energy sorng devces and elecromobles. Papers above concluded ha hrough opmzng users power consumpon he peak-valley dfference of power sysems can be reduced effecvely and so does users power coss. The exsng researches acheved he modelng of CT applances bu s focused on elecrcal applances (elecromobles sorage baeres PV baeres ec.). Acually he behavour of he hermodynamc equpmen such as ar condoners and waer heaers has played an mporan role n he whole CP's elecrcy consumpon characerscs. More dealed model research should be carred ou. Ths paper presens an energy managemen model wh mulple CTs n a CP. Models of he ransferable applances; energy sorage devces and hermodynamc equpmen n CTs are bul. The model s appled o a four-ct demonsraon example whch shows ha he model can acheve an opmal managemen of CT load and he valdy and feasbly of he model are verfed. 2. Energy Managemen Model for Commercal Parks 2.1. Classfcaons and Characerscs of Applances n Commercal Parks Accordng o he operang characerscs of CTs applances and conrol mehods CT applances can be dvded no four caegores. Non-ransferable Applances: When he user gves a work order he unconrollable applances mus respond mmedaely whou delay. Such applances sar/sop and operang power are no conrolled by he CPEMS. Such applances are mosly lghng and eneranmen applances whose sar/sop has a srong randomness varyng wh user s habs. Typcal represenaves are ncandescen lamps elevsons and so on. Transferable Elecrcal Applances: Users can se he workng me of such elecrcal applances n advance. In he me range se by he user he CPEMS can be free o arrange he workng me of elecrcal applances. Furher such applances can be dvded no wo caegores as nerrupble and unnerrupble. The dfference beween hese wo caegores s wheher he applance can be nerruped when s workng. For example he dshwasher can be se o work n a perod of me beween 19:00 and 22:00 bu once he dshwasher sars o work canno be nerruped unl he dshwasher complees he job. On he conrary ake elecromobles for example he user can se o fnsh he chargng beween 20:00 and 7:00 and he chargng process can be nerruped for many mes. Energy Sorage Devces: Because he peak-valley hours and peak-valley generaon amoun of dsrbued power s dfferen o ha of CPs load clens can buy energy sorage devces whch wll sore or release elecrc power o ake full advanage of dsrbued power. For CTs consderng ha he ypcal peak value of CTs load s of kw level usually lhum baeres and lead baeres can be used as energy sorage devces Thermodynamc Equpmen: I can be seemed as a specal knd of ransferable applances. Because of hermodynamc equpmen lke refrgeraor ar condoner and waer heaer has a emperaure propery he change of nernal and exernal emperaure should be aken no consderaon whle modelng and hea exchange process should be modeled. To ensure users comfor hermodynamc equpmen s ofen se o work n a emperaure range whch s usually se by users and vared wh dfferen lvng habs of users Modelng of CPEMS In CPEMS applances operaon consran condons should be concluded accordng o dfferen ypes of applances operaon characerscs. The objec s o mnmze he cos of elecrcy purchase and he opmal operaon schedule of CTs applances should be made. In hs paper he me nerval of CTs applances workng schedule s 15 mnues. 2

4 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ Dsrbued generaor. For CTs renewable energy sources lke small sze wnd drven generaors PVs and bomass power generaon can be used. Acually PVs wh solar panels are he mos popular used clean energy. So n hs paper PV s modelled as an example of dsrbued generaon. Consran condon of PV s: pv pvmax 0 p p (1) p Among he equaon above p pvmax pv s he h solar panel s power of generaon n he h me nerval. s he h solar panel s maxmum power of generaon n he h me nerval whch can be obaned by makng he solar panel work n Maxmum Power Pon Trackng (MPPT) mode. When CTs smar grd and power grd operae ogeher SEMS can le PVs work n MPPT mode sellng exra elecrcy generaed by PVs o power grd o gan more prof Non-ransferable applance. Non-ransferable applances are of srong randomness grealy nfluenced by dfferen users lvng habs. They re he drec resul of users elecrcy consumpon modes. Based on users hsory elecrcy consumpon nformaon ypcal load curves of nonransferable applances can be obaned hrough cluserng algorhm n [11]. Le he h CT s ypcal power of non-ransferable applances n he h nc me nerval be EL. h h Transferable applance. Le he ransferable applance s workng condon n me c c nerval be u. u s a bnary varable. A value of 0 sands for shudown saus and value of 1 sands for operang saus. Consran condon of Transferable applance s: c s e u 0 or (2) end c u D (3) 0 c c c on u u 1 uk 0 k T 1 (4) s Among he equaon above s he earles sar me of he h e ransferable applance and s he laes shudown me of. D s he me ha he h ransferable applance needs o fnsh workng. 0 and end respecvely sands for SEMS s sar me and end me for plannng. s mnmum workng me afer ransferable applance boong. Equaon (2) ndcaes ha ransferable applance can only complee s work whn he me perod specfed by he user. and s specfed by he user accordng o hs or her own habs and he user s e can change hem a any me accordng o he need. For example he user can ake he washng machne as a ransferable applance whch s opened o he operaors of CPEMS and specfy he me ha he washng machne can work beween 18:00 o 22:00 every day. Ths schedule s nformed o he CPEMS operaor a he plannng sage before day. One day he user needs o complee he laundry work beween 10:00 o 12:00 for some reason. Then he needs o nofy he CPEMS operaors a realme adjusmen sage. The CPEMS operaors wll adjus he work plan o mee he user's demand for elecrcy. Equaon (3) ndcaes ha he sar-up me of he ransferable applance n one day s equal o he me requred o complee he work hus ensurng he compleon of he ask. The value of D s deermned by he applance self. Equaon (4) s consraned by he mnmum operang me of he ransferred elecrcal applance. As for unnerrupble loads T on on T D ensurng ha elecrcal applances canno be sopped unl s fnshed afer boong. As for nerrupble loads T on D 3

5 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ whch means ha he applance can be sared and sopped several mes. elecrcal characerscs of he applance self. on T s decded by he Energy Sorage Devce. Energy sorage devce s no a general sense of applances and can be seen as he specal equpmen whch can mnmze he cos of power purchasng. Therefore sar and shudown of energy sorage devces wh her power should be conrolled by he CPEMS operaors. Consran condon of Energy sorage devce s: ch ds p ch p soc soc 1 (5) C mn max soc end soc soc soc (6) (7) p p (8) ds ch 0 Among he equaon above soc s he sae of charge (SOC) of he h energy sorage devce n he h ch ds me nerval. p and p s chargng power and dscharge power of he h energy sorage h devce n he me nerval respecvely. ch s energy converson effcency of energy sorage h h devce. C s he volume of he energy sorage devce. s he energy sorage devce s mn max mnmum SOC a he end of he plannng perod. soc and soc sands for mnmum and maxmum charge sae respecvely of h energy sorage devce. Equaon (6) s a consran on he charge sae of he energy sorage sysem. For chemcal baery ype energy sorage sysems he larger he deph of dscharge wll generally shoren he baery lfe whch s parcularly evden for lhum-on baeres. Therefore he general baery ype energy sorage sysem usually se he maxmum and mnmum sae of charge o proec he baery. soc / max soc wll be provded by he energy sorage sysem manufacurer. Equaon (7) ensures ha a he end of he opmzaon perod he energy sorage devce manans a ceran amoun of energy o ensure he ably o adjus for he nex opmzaon perod. Equaon (8) consrans ha a sysem wh mulple energy sorage sysems canno be n a sae of charge and dscharge a he same me. If par of he energy sorage devce s n he chargng sae and he oher par of he energy sorage devce s also n he dscharge equpmen hs s also a behavor of energy wasng. However he formula (8) s essenally a quadrac consran wh mulple cross erms. Ths ype of consran wll desroy he convexy of he problem and cause he problem o be dffcul o solve. To solve hs problem flag ch ch varables f s se. f ndcaes wheher he energy sorage devce can be recharged n he h me perod. A value of 0 means ha can be recharged whle value of 1 means no. Equaon (8) can be re-expressed as: ch ch chmax 0 p f p (9) ch ch dsmax 0 p 1 f p Thermodynamc Equpmen. The key o he modellng of hermodynamc equpmen s how o descrbe he hea exchange process. Take ar condonng as an example assume ha he nernal r ou emperaure of he room s T (gnorng he room emperaure dfference) oudoor emperaure st. The hea change n he room s caused by he hea exchange beween he ar condoner and he room as well as he hea exchange beween he room and he ousde. The whole process can be descrbed as: mn 4

6 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ d M ar c d d HVAC loss (10) dq co co he he p p d (11) r dt dq dq HVAC r ou dq T T (12) d R loss eq Among he equaon above M s he qualy of he ar n he room. c s hea capacy per un mass of ar a sandard pressure. equpmen. / he co ar p / he co p h s he heang/coolng power of he hermodynamc s he heang/coolng effcency of he h hermodynamc equpmen. dq equvalen hermal ressance of he room a ha me. d HVAC Req s he s he hea exchange beween he dq ar condoner and he ndoor un per un me. s he hea exchange beween he d loss oudoor un and ndoor un per un me. I should be noed ha c s a hermodynamc consan. M ar s relaed o he sze of he room. For a CT M ar can be regarded as consan. Req s relaed o he h ou curren room ype and venlaon sae. Assume ha p and T s a consan over a perod of me. Solvng he equaons (10)-(12) and dscrezng he resuls a formula can be obaned: r he co he he r ou T 1 R 1 eq Kh p p T K h 1 Kh T (13) Among he equaon above Kh exp (14) M ar cr eq Smlar resuls have been repored n [9] [10] bu hey do no dsngush he heang and coolng power of ar-condonng equpmen whch lms he applcaon of he model. Generally n order o ensure he comfor of he user he user can se he upper and lower lms of he ndoor emperaure he CPEMS operaor wll keep he ndoor emperaure whn he range: rmn r rmax T T T (15) 2.3. Operaonal Sraegy of CPEMS The user's dsrbued power generaon sysem wll mee he user's own needs of elecrcy preferenally and he exra elecrcy can be sellng o he power grd o gan more prof. If he PVs equpmen and energy sorage devces are no suffcen o mee he CT elecrcy demand users need o purchase elecrcy from he grd. CPEMS operaors need o ensure he power balance of CTs smar grd by sellng and buyng elecrcy from he grd. Consran condon of can be descrbed as: buy sell nc c c co he ch ds pv p p EL u p p p p p p (16) Among he equaon above p / p s he elecrc power ha CPEMS buys or sells o he grd n buy sell he h me nerval. Ths elecrc power s he sum of he power purchased and sold by he CTs and power grd who s responsble for he CPEMS operaor. As a resul he CPEMS operaor canno 5

7 Power (kw) 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ smulaneously purchase and sell elecrcy. So Le be purchased or no n h me nerval. Consran condon of f s: g Among he equaon above g f be a varable o show wheher elecrcy can buy g buymax sell g sell max p f p p f p (17) buymax p s he CPEMS operaor s maxmum purchase power sellmax deermned by he dsrbuon nework power supply capacy. p s he CPEMS operaor s maxmum sold power deermned by he capacy of he CTs smar grd s oule nverer. CPEMS operaor's operang goal s o acheve he lowes cos of elecrcy purchase under he premse ha meeng he needs of mulple CTs elecrcy demand. I can be descrbed as: buy buy sell sell mn p c p c (18) Among he equaon above buy c / c s he real-me prce a whch he CPEMS operaor buys / sell h sells elecrcy o he grd n he me nerval. Equaons (1)-(17) are he consrans of he opmzaon problem. As a whole he problem can be expressed as a mxed neger lnear programmng problem. 3. Demonsraon Examples 3.1. Parameer Sengs The daa presened n hs paper s from a commercal park of a smar grd demonsraon projec. Four CTs n he commercal park are seleced as model CTs wh solar panels and energy sorage devces nsalled. Accordng o he proposed CPEMS model hsorcal daa of power consumpon should be colleced frs durng pre-research phases. Afer hen oban he ypcal elecrcy consumpon paern of unconrollable applances by calculaon. Such curves of he four CTs are shown n fgure 1. The ransferable load parameers energy sorage devces parameers and hermodynamc equpmen parameers of he four CTs are shown n Table 1-3 of appendx CT A CT B CT C CT D Power of PVs Ousde emperaure Tme (h) Fgure1. The ypcal elecrcy consumpon paern of unconrollable applances Fgure 2. The ousde emperaure and solar power oupu Exposed o he sunlgh solar panel s generaon daa and oudoor emperaure condons s shown n Fgure 2. The oudoor emperaure can be obaned from he local meeorologcal bureau and he PV power can be calculaed from he daylghng condon daa. The elecrcy purchasng prce s dfferen n peak and valley hours. The me beween 6:00 and 22:00 s peak hours and he prce s 0.56 Yuan/kWh. The me beween 22:00 o 6:00 of he nex day s valley perod and he prce s 0.28 Yuan/kWh. 6

8 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ The demonsraon examples use MATLAB 2014a and YALMIP [12] o complee he calculaons where he soluon for mxed neger programmng s done usng IBM ILOG CPLEX All calculaons are done on a personal lapop wh a 2.6G clock speed and 8G of memory wh a processor model M. 4. Resul Analyss In order o verfy he effecveness of he proposed energy managemen model he followng wo suaons are demonsraed and compared. Suaon 1: No CPEMS parcpaes. All he ransferable load can begn o work a allowed workng me. When he PV power s suppled o he user he excess elecrcy s sold o he power grd. The elecrcy prce s 0.3 Yuan/kWh for peak hours and 0.15 Yuan/kWh for valley perod. Suaon 2: The users make an agreemen wh he CPEMS operaors and he operaors wll arrange he ransferable load s and energy sorage devces operaon. On he bass of purchasng power and sellng elecrcy he operaors can reduce 7% of he elecrcy purchasng cos and gve a subsdy of 7% of he elecrcy sales o he users and subsdze he users' energy sorage capacy accordng o 0.02 Yuan/(kWh day). In he wo suaons he CTs elecrcy coss are shown n Table 1. The operaon of CPEMS n suaon 2 s shown n Table 2. Table1. Elecrcy coss n dfferen suaon (n Yuan) Clens Suaon 1 Suaon 2 CT A CT C CT C CT D Toal Table 2. The prof able of CPEMS operaors (n Yuan) Elecrc prce whou subsdy Elecrcy purchasng subsdy Subsdy Elecrcy sellng subsdy Energy sorng subsdy Elecrc prce wh subsdy Elecrcy Purchasng prce from I can be seen ha n Suaon 2 where he CPEMS parcpaes mos of he users' elecrcy purchasng coss are sgnfcanly lower han ha n Suaon 1 due o he subsdy gven by he CPEMS operaor. In hs case CTs are wllng o sgn agreemen wh he CPEMS operaor o oban he subsdy. Also n hs suaon he CPEMS can reduce he oal cos of purchasng power by opmzng he elecrcy plan of he four CTs n spe ha subsdzng he user ncreases he operang coss. Generally speakng CPEMS s profable. Ths shows ha he operang mode n hs paper can help users and CPEMS acheve a wn-wn suaon. 5. Conclusons Ths paper presens a mul-ct energy managemen model wh hermodynamc equpmen. The demonsraon examples resul shows ha under CPEMS mechansm more PV power wll be grd Prof 7

9 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ consumed locally and users coss are reduced. A he same me he CPEMS operaor gans prof achevng a wn-wn suaon. In hs model he effec of he uncerany of he renewable energy s no aken no accoun. Usng he mahemac ools such as robus opmzaon and sochasc programmng o quanavely consder he nfluence of PV forecas error on he specfed elecrcy plan and mprovng he robusness of he elecrcy plan s he drecon of nex research. 6. Acknowledgmens We hank he suppor by Sae Grd Technology Program ( F). 7. Appendx Appendx Table 1. Parameers of Transferable Applances Number CT Applance name Workng me duraon Earles workng Laes workng Mnmum workng me Power (mn) hour hour duraon(mn) (kw) 1 A dehumdfer 40 09:00 19: A dsnfecon cabne 30 18:00 20: B elecrc bcycle 45 1:00 8: B dryer 70 1:00 7: B dsh-washng machne 45 18:00 22: B sweepng robo 50 9:00 17: C washng machne 60 11:00 23: C elecromoble 200 1:00 8: C dsh-washng machne 45 8:00 18: C dehumdfer 85 09:00 19: D washng machne 35 16:00 23: D elecromoble 250 1:00 9: Appendx Table 2. Parameers of Energy Sorage Devces Number CT Maxmum chargng power (kw) Maxmum dschargng power (kw) Chargng effcency Capacy (kwh) Mnmum sae of charge Maxmum sae of charge Inal sae of charge 1 A B C D Appendx Table 3. Parameers of Thermodynamc Equpmen Number CT Equvalen hermal ressance Inal emperaure Mnmum seng emperaure Maxmum seng emperaure Maxmum coolng power (kw) Maxmum heang power (kw) 1 A B C D References [1] TONG Humng DENG Lan PAN Shuangshuang. Inroducon of Zhejang homes dsrbued phoovolac power generaon projecs nework managemen and echncal nnovaon [A]. Chna Elecrcy Councl of Scence and Technology Developmen Servce Cener. [2] YAAGOUBI N MOUFTAH H T. User-aware game heorec approach for demand managemen[j]. Smar Grd IEEE Transacons on (2): [3] STEPHENS E R SMITH D B MAHANTI A. Game heorec model predcve conrol for dsrbued energy demand-sde managemen[j]. Smar Grd IEEE Transacons on (3): [4] ESTHER B P KUMAR K S. A survey on resdenal Demand Sde Managemen archecure approaches opmzaon models and mehods[j]. Renewable & Susanable Energy Revews : [5] GHASEMI A SHAYEGHI H MORADZADEH M e al. A novel hybrd algorhm for elecrcy prce and load forecasng n smar grds wh demand-sde managemen[j]. IEEE Transacons on Power Sysems [6] JINGHUAN M CHEN H H LINGYANG S e al. Resdenal load schedulng n smar grd: A cos effcency perspecve [J]. IEEE Transacons on Smar Grd (2):

10 2017 Inernaonal Conference on Envronmenal and Energy Engneerng (IC3E 2017) IOP Publshng IOP Conf. Seres: Earh and Envronmenal Scence (2017) do : / /63/1/ [7] JIN C TANG J GHOSH P. Opmzng elecrc vehcle chargng wh energy sorage n he elecrcy marke[j]. Smar Grd IEEE Transacons on (1): [8] LIANG Y HE L CAO X e al. Sochasc conrol for smar grd users wh flexble demand [J]. Smar Grd IEEE Transacons on (4): [9] HUBERT T GRIJALVA S. Modelng for resdenal elecrcy opmzaon n dynamc prcng envronmens [J]. Smar Grd IEEE Transacons on (4): [10] ZHOU L Modelng and opmal dspach for resdenal load based on home energy managemen sysem under me-of-use prcng[j] Power Sysem Technology (39): [11] HINO H SHEN H MURATA N e al. A versale cluserng mehod for elecrcy consumpon paern analyss n homes [J]. Smar Grd IEEE Transacons on (2): [12] LÖFBERG J. YALMIP: A oolbox for modelng and op-mzaon n MATLAB[C]//Compuer Aded Conrol Sys-ems Desgn 2004 IEEE Inernaonal Symposum on. IEEE 2004: