V.G.Umalem 1, S.B.Warkad 2 1 Department of Electrical Engineering Priyadarshini College of Engineering Nagpur, Maharashtra, India ABSTRACT

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1 2017 IJSRSET Volume 3 Issue 8 Prnt ISSN: Onlne ISSN : Themed Secton : Engneerng and Technology Comparson of Locatonal Margnal Transmsson Prcng V.G.Umalem 1, S.B.Warkad 2 1 Department of Electrcal Engneerng Pryadarshn College of Engneerng Nagpur, Maharashtra, Inda 2 Department of Electrcal Engneerng, P. R. Pote College of Engneerng Amaravt, Maharashtra, Inda ABSTRACT Locatonal margnal prce s requred n restructured power system.it s requre creatng an effectve prcng scheme that to provde the useful nformaton to generaton, transmsson secton and customers. These transmsson prcng depends on generator, load levels and transmsson lne constrants. Transmsson lne constrants result s varatons n energy prces throughout the network. The proposed approach s based on AC optmal power flow model wth consderng of losses. Resultng optmzaton problem s solved by lnear programg approach. Locatonal Margnal Prcng methodology s used to detere the energy prce for transacted power and to manage the network congeston and margnal losses. Varaton of LMP values wth transmsson constrant condtons also studed. Smulaton s carred out on 220kV, 400Kv & 765kV MSETCL system of Maharashtra transmsson lne for real data bus system and the results are presented. Keywords: Locatonal Margnal Prcng, Optmal Flow, transmsson prcng I. INTRODUCTION By Tradton, power ndustry s vertcally ntegrated, n whch the generaton, Transmsson and dstrbuton are arranged collectvely as a sngle utlty to serve ts customers. Due to central operaton of transmsson and dstrbuton system t wll reman n a monopoly mode. Under the deregulated electrcty `market envronment, transmsson networks play a vtal role n supportng the transacton between producers and consumers. Due to Transmsson Open Access (TOA the power flow n the lnes reach the power transfer lmt and so t wll leads to a condton known as congeston [1-2]. The congeston may be caused due to a mxture of reasons, such as transmsson lne outages, generator outages and change n energy demand. Transmsson congeston has mpact on the entre system as well as on the ndvdual market partcpants.e. sellers and buyers. Wthout congeston low cost GENCOs are used to meet the load demand but f congeston s present n the transmsson network then t prevents the demand to be met by the lowest-prced resources due to mentoned transmsson constrants and ths leads to the allocaton of hgher prce. There are two types of prcng methods are avalable n practce for congeston management [10]. They are unform and non-unform prcng structure. In ths paper congeston s managed by means of Locatonal Margnal Prcng (LMP.e. non-unform prcng structure. The LMP at a locaton s defned as the margnal cost to supply an addtonal MW ncrement of power at the locaton wthout volatng any system securty lmts [1]. Ths prce reflects not only the margnal cost of energy producton, but also ts delvery. Because of the effects of both transmsson losses and transmsson system congestons, LMP can vary sgnfcantly from one locaton to another. If the lowest prced electrcty s allocated for all Locaton LMP values at all nodes wll be same. If congeston present n the system lowest cost energy cannot reach all locaton, more expensve generators wll allocated to reach out the demand. In ths stuaton LMP values wll be dffer from one locaton to another. ISO deteres the generaton and demand schedule as well as LMPs based on ncreased socal welfare mzaton, subject to system operatonal. LMP = generaton margnal cost + congeston cost +margnal loss cost LMP s obtaned from the result of Optmal Flow (OPF. Ether AC-OPF or DC-OPF s used to detere IJSRSET Receved : 20 Nov 2017 Accepted : 13 Dec 2017 November-December-2017 [(3 8 : ] 109

2 the LMP [7]. To reduce the complexty n the calculaton n ths paper DC-OPF s used. In DC-OPF only real power flow s consdered [6]. Dfferent types of optmzaton models are used for LMP calculatons lke LP and Lagrangan. Among these n ths paper quadratng programg s used to solve the optmzaton problem. To reduce the gap between transmsson capacty and electrcty demand, trend s now to ncorporate HVDC transmsson n the exstng AC networks to gan techno-economcal advantages of the nvestment. II. REAL TIME- ENERGY MARKETS Restructured power market conssts of dfferent types of market. An energy market s a place where the fnancal tradng of electrcty takes place. It naturally conssts of a day-ahead market and real-tme market, whle the ancllary servce markets are able to provde servces such as synchronzed reserve, regulaton and relable operaton of transmsson system. The day-ahead market s a type of forward market and runs on the day before the functonng day [1-2]. Generaton offers, demand bds, and blateral transactons are accepted by the Day- Ahead market n the regulated market tmelne. Vrtual offers and bds are also receved to ncrease the market lqudty. Load forecastng tool s used to predct the load n the submtted bds. As a result of runnng the optmzaton model the generaton dspatch and electrcty prces for each hour of the operatng day was calculated. The man objectve of ths problem s mzaton of total cost subjected to energy balance constrant and transmsson constrant. flow s obtaned by ACOPF model wth consderng of losses. In ths OPF reactve power s gnored and the voltage magntudes are assumed to be unty [12]. III. OPTIMAL SOLUTION (A AC System Equatons For n bus system, let P ( p1,..., pn and Q ( q 1,..., qn and reactve power demands of bus-, where p and q be actve, respectvely. The varables n power system operaton defned as X,...,.e. real and magnary parts of ( x 1 xm each bus voltage. Then the problem of a power system for gven load ( P, Q can be formulated as OPF problem. Mnmze f ( X, Q for X (Objectve functon subject to S ( X, Q 0 constrants T ( X, Q 0 Internatonal Journal of Scentfc Research n Scence, Engneerng and Technology (jsrset.com (Equalty (Inequalty constrants T where S ( X ( s1( X, Q,..., sn1 ( X, Q and T ( X ( t1( X, Q,..., tn2 ( X, Q have T n1and n 2 equatons, and are column vectors. A T s the transpose of vector A. f ( X, Q s a scalar, generator cost functon f F (P g F 1 havng cost characterstcs represented by, ( a P 1 2 g b P g c system constrants.e. T ( X, Q 0 to be satsfed are- (1 Vector of equalty constrant.e. power flow balance s, P P P P g Qg d dc Qd Qdc QL Here suffx d represents the demand, g s the generaton, dc represents dc teral and L stransmsson loss. (2 Vector of nequalty constrant as ( mum and mum lmts on real and reactve power generatons s Pg Pg Pg ( 1, 2,..., Qg Qg Qg L ( 1, 2,..., ( mum and mum lmts on bus voltage magntudes s, V V V ( NV 1, NV 2,..., (8 ( lmts on transmsson lne power flow (MVA lmts s, P f P f P f ( f 1, 2,..., Noele (B Electrcty Spot Prce Equatons The real and reactve power cost at bus ' s the Lagrange multpler functon of the equalty and nequalty constrants calculated by solvng frst order condton of the Lagrangan, partal dervatves of the Lagrangan wth respect to every varable concerned. So 578

3 the Lagrange functon of equatons are defned as a cost,the real and reactve cost at bus s the Lagrange multpler functon of the equalty and nequalty constrants calculated by solvng the frst order condton of the Lagrangan, partal dervatve of the Lagrangan wth respect to every varable concered. So the Lagrange functon of equaton s defned as a cost functon L ( 2 a Pg b PG c p ( Pd Pg Pdc PL q ( Qd Qg Qdc QL NV 1 p ( ( l Pg Pg pu Pg Pg ql ( Qg Qg qu ( Qg Qg ( ( vl V V vu V V ( l u ( Noele Noele p ( fl P f fu ( P f P p P f f where, l and u are lower and upper lmts; λ= (λ 1,,λ n s the vector of Lagrange multplers concernng equalty constrants; ρ = (ρ 1,,ρ n are the Lagrange multplers concernng nequalty constrants. Then at an optmal soluton ( X,, for a set of gven ( P, Q, Spot prce of real and reactve power for bus s expressed for 1,..., n are, L ( X,,, Q p, p L ( X,,, Q q, = q = f S T p p p (21 f S T q q q The dfference ( p, - p, j represents real transmsson charges from bus-j to bus-. The system margnal cost created by an ncrement of real and reactve power load at bus respectvely. Ths methodology has been smulated n MATLAB software and results are obtaned for several condtons and constrants tested over software 220kV, 400kV& 765kV MSETCL network. IV. RESULTS FOR MSETCL SYSTEM Ths paper consdered for 220kV, 400kV & 765kV of Maharashtra transmsson lne bus system Locatonal Margnal Prcng s computed by mplementng AC-DC OPF based methodology. The electrcty LMPs are computed s shown n Table-I, Table-II & Table-III here we calculated locatonal margnal prces on each node, the prces are change accordng to load varaton. Table 1. Locatonal Margnal Prces for 200kV (Volts (p.u. Reactve (p.u. Spot Prce (Rs./kWh Table 1. Locatonal Margnal Prces for 400kV (Volts (p.u. Reactve (p.u. Spot Prce (Rs./kWh Internatonal Journal of Scentfc Research n Scence, Engneerng and Technology (jsrset.com 579

24 1.01 0.02 0.00 0.00 2.87 25 0.96 0.05 1.50 0.04 2.76 26 0.97 0.01 0.13 0.46 2.88 27 1.02 0.04 0.08 0.06 2.74 Table 3. Locatonal Margnal Prces for 765kV (Volts (p.u. Reactve (p.u. Spot Prce (Rs.

4 Table 3. Locatonal Margnal Prces for 765kV (Volts (p.u. Reactve (p.u. Spot Prce (Rs./kWh Graph 1. Comparson of 200kV/400kV/765kV MSETCL Network V. CONCLUSION Ths paper also presented and mplemented the relatve electrcal dstance based allocaton methodology of transmsson tarff for a real 220kV, 400kV & 765kV of Maharashtra transmsson lne system. The method s nherent advantages, t has farly allocated power transactons based on relatve electrcal dstance between njecton node and drawal node. The numercal results are shown n Table I, Table II & Table III ndcate the locatonal margnal prces at dfferent buses. Transmsson nvestments are needed to reduce electrcty prces as well as to releve congeston n an mportant transmsson lnes. In ths context, AC-DC OPF based electrcty nodal prces are evaluated for MSETCL system. The prces are varaton n Graph I Ths paper s evaluated wth reference to hourly varatons n bus voltage behavor, electrcty nodal prces, generaton behavor and ther payments and transmsson utlty s revenues n terms of transmsson congeston charges. VI. REFERENCES [1]. A.J.Conejo,M.Carron,J.M.Morales,Decson Makng Under Uncertanty n Electrcty Markets,New York,NY USA:Sprnger,2010. [2]. Wllams J.,Ghanadan R.,"Electrcty reform n developng and transton countres:a reapprasal",energy 31,pp ,2006. [3]. Zhang Y.F.,Parker D.,and Krkpatrck C.,"Electrcty Sector Reform n Developng Countres:an econometrc assessment of the effects of prvatzaton,competton and regulaton",workng paper no.31,aston ness School Research Insttute,Aston Unversty,Brgham B4 7ET,November [4]. Bacon,R.W.and J.Besant-Jones,"Global Electrc Reform,Prvatzaton and Lberalsaton of the Electrc Industry n Developng Countres",Annual Revew of Energy & the Envronment,no.26,pp ,2001. [5]. F.C.Schweppe,M.C.Carams,R.D.Tabors,R.E.Boh n,spot Prcng of Electrcty,Kluwer Academc Publshers,Boston,p.384,1988. [6]. M.Rver and I.J.Perez-Araga,"Computaton and decomposton of spot prce far transmsson prcng," n 11th PSC conference,avgnon,franca Agosto,pp.39-46,1993. [7]. D.Fnney, H.A.Othman, and W.L.Rutz, "Evaluatng transmsson congeston constrants n system plannng," IEEE Transactons on Systems,vol.12,no.3,pp , August [8]. P.D.C.Wjayatunga, B.J.Cory and M.J.Short,"Securty and revenue reconclaton n optmal transmsson prcng", IEE Proc.- Generaton, Transmsson, Dstrbuton, vol.146,no.4,pp ,july Internatonal Journal of Scentfc Research n Scence, Engneerng and Technology (jsrset.com 580

5 [9]. Ka Xe,Yong-Hua Song, John Stonham,Erkeng Yu,and Guangy Lu, "Decomposton Model and Interor Pont Methods for Optmal Spot Prcng of Electrcty n Deregulaton Envronments", IEEE Transactons on Systems,vol.1,no.1,pp.39-50,February [10]. G.Ward,N.R.Watson,C.P.Arnold,A.J.Turner,and B.J.Rng,"Inverson of Tme Spot Prces n the Drecton of Flow n a Transmsson Lne",IEEE Transactons on Systems,vol.15,no.4,pp ,November [11]. S.B.Warkad,Dr.M.K.Khedkar,Dr.G.M.Dhole, "Optmal Electrcty Nodal Prcng n a Restructured Electrcty Market", Journal of The Insttuton of Engneers (Inda, Volume 91,pp.29-35,June 18,2010. [12]. Cervgn, G., & Perekhodtsev, D.(2013."Wholesale Electrcty Markets",In P.Rnc & G.Cervgn (Eds., The Economcs of Electrcty Markets:Theory and Polcy.Edward Elgar.2013, Retreved from Internatonal Journal of Scentfc Research n Scence, Engneerng and Technology (jsrset.com 581

Proceedings of the 10th WSEAS International Confenrence on APPLIED MATHEMATICS, Dallas, Texas, USA, November 1-3,

Proceedings of the 10th WSEAS International Confenrence on APPLIED MATHEMATICS, Dallas, Texas, USA, November 1-3, roceedngs of the 0th WSEAS Internatonal Confenrence on ALIED MATHEMATICS, Dallas, Texas, USA, November -3, 2006 365 Impact of Statc Load Modelng on Industral Load Nodal rces G. REZA YOUSEFI M. MOHSEN EDRAM