Nodal Market Power Detecton under Locatonal Margnal Prcng A. Soabad* and A. Akbar Foroud* (C.A.) Abstract: Ths paper proposes an ndex for nodal market power detecton n power market under Locatonal Margnal Prcng (LMP). Ths ndex s an ex-ante technque to detect the market power. More precsely, ths crteron detects the potental exercsng market power regardless detectng the actual market power. Also t s obvous that prcng and market clearng method affect the potental exercsng market power. Dfferent potental market power exsts n dfferent prcng methods. Ths ndex has been analyzed under LMP method whch seems to be a desrable envronment to exercse market power. In LMP method by load growth, n some determned load levels whch s called Crtcal Levels (), locatonal margnal prces have step change. Ths step change n locatonal margnal prces causes step change n revenue and beneft s. So t s sgnfcant to detect the behavor s n the. The proposed crteron has been tested on constant system load and for two test system. Keywords: Locatonal Margnal Prcng, Market Power Detecton, Nodal Market Power. 1 Introducton1 Market power detecton s a complex ssue n restructured power market. Technques that have been appled to detect market power are prmarly classfed to two categores [1]: 1-ex-ante technque, whch are appled to detect the potental for market power and 2- ex-post technques, whch are appled to detect the actual market power. The most usual ndex for ex-ante technques s HHI ndex [2]. Ths ndex representng the number market partcpants and ther market shares n power market. The HHI s calculatng through a sum the squares market share market partcpants. Ths ndex has been formulated as below: HHI = N S = 1 2 (1) where N s a number market partcpants and S s the th market partcpant share. If the HHI s greater than 1 n percentage, the market power exsts n power market. Ths ndex express that as much as the number power market partcpants decrease and ther market share ncrease the potental power market exercsng ncrease. Ths ndex s not a comprehensve ndex snce n some cases a market partcpant wth a small share market could prtably change the prce especally n Iranan Journal Electrcal & Electronc Engneerng, 214. Paper frst receved 1 June 213 and n revsed form 1 Sep. 213. * The Authors are wth the Department Electrcal Engneerng, Semnan Unversty, Semnan, Iran. E-mals: Soal8@gmal.com and aakbar@semnan.ac.r. the stuaton that demand s close to the system generaton capacty. Also ths ndex does not consder the transmsson constrant and also load varaton. Another technque n market power detecton from the vew pont load elastcty s Lerner Index (LI) [3, 4]. Ths ndex has been formulated as below: ρ mc 1 LI = = (2) ρ ε d where ρ denotes the market clearng prce and mc s margnal cost at the frm prt-maxmzng output and the term ε denotes the elastcty demand seen by the d frm. Ths crteron vares from 1 to. When the market s completely compettve the LI s zero snce ρ mc denotes that margnal cost unt s equal to the market prce. The major dffculty wth ths ndex s determnng margnal cost generaton unts. Another market power detecton ndex s called NMRS whch s the abbrevaton Nodal Must Run Share [5]. Based on ths ndex the potental exercsng market power by every n the system s proporton to the mnmum delvered power a generator at each node system ( must P gk, ). The NMRS for generators A at the bus system have been formulated as below: must P k A gk, NMRS A, =, = 1,2,..., N. (3) p d Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214 45
The above ndex doesn t consder the load varaton and generaton cost s. The generaton cost a and n another word, how ths s effcent n comparson to the other s n the power market determnes ts power generaton through OPF problem. So OPF problem determnes the generaton commtments n the system and consderng the mnmum delvered power a generator at each node system can't comprehensvely express the effcency and real stuaton a n power market especally when the market has abundant s. To probe further about the defects ths ndex, consder the smple 3 bus system [6] whch has been depcted n Fg. 1. The detal data ths system s avalable n chapter 6 [6]. The nodal market power each based on [5] ndex has been depcted n Table 1. Based on the above ndex s A, C and D has no potental exercsng market power snce wthout each these s the system load and other system constrantt accordng to the optmzaton problem [5] can be satsfed and the mnmum delvered power these s to each system bus s zero (accordng to the proposed ndex [5]). So s A, C and D have no potental exercsng market power accordng to ths ndex. Only B has the potental exercsng market power snce wthout ths the system load can't be met and other system constrant n proposed optmzaton problem n [5] can't be satsfed. So ths ndex that consders the mnmum delvered power s to each bus system may be equated to zero for s whch has small share n system load supply as above example. But durng the perod whch demand s closed to generaton capacty (peak tme) a wth small share n system load supply, can exercse market power. Also a wth low generaton cost that has small share n system load supply can have more potental exercsng market power n comparson to a wth hgh generaton cost that has major share n system load supply [7]. Also n ths ndex the load assumed to be constant and load varaton and system have not been consdered n ths ndex. Fg. 1 Three bus system wth generaton and load data. Table 1 The nodal market power each n each bus system based on [ 5] ndex. NMRS ndex A B C D BUS1.41 BUS2 BUS3.16.21 From another aspect n dfferent prcng and market clearng mechansm, dfferent potental power market exsts [7-9]. In the LMP method, after the bds submtted by the generators, the ISO wll run OPF and f there s no system constrant volaton the prce prle s unform n all system buses, but f a system constrant volates ts lmt, the ISO wll re dspatch the generaton so as the constrant volaton removed [6]. One the desrable prcng envronments for market power seems to be LMP system snce the system constrant volaton encourages s to exercsee market power [1-13]. Investgatng and montorng the potental exercsng market power under LMP system s necessary and sgnfcant snce LMP opens the door for exercsng market power under certan condton system. In another word LMP does not guaranteee compettve markets, nor does t prevent the market power exercsng. Some features LMP system whchh may ncrease market power exercsng are [6, 14]: 1- If a generator capacty s fully dspatched, the locatonal prce at ths generator bus wll be determnedd by the bds other generators and wll be greater than or equal to the generator s energy bd for that capacty segment. 2- In most stuatons, but not all, the locatonall margnal prces at most locatons wll be determned by the bds generators at other locatons. From another vew, load varaton n LMP system can ncrease the potental exercsng market power. growth causes the step change n locatonall margnal prces due to the system constrant volatons [15]. In the determned load level whch s called Crtcal Level () the OPF constrantss volaton cause the step change n locatonal margnal prces. The step change locatonal margnal prces at each bus s a golden opportunty for each to ncrease ts benefts. So the possblty exercsng market power between market partcpants ncrease n. So detectng the market power n the dfferent load levels a system s vtal for each market operator. LMP system s a vulnerable prcng system due to ts dependency on the structure system. So the nodal prces are dependng on the structure the system. Ths dependency has been shown n detal n secton 4-2. So t s vtal to propose an ndex to detect the structural potental market power under LMP system whch has 46 Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214
been done n ths research. Also the load varaton n LMP system based on the structural stuaton system can ncreasee the structural potental exercsng market power n some buses system or decrease the structural potental exercsng market power n the same buses system for a specal. So t s vtal for system operator to dentfy the s potental exercsng market power n dfferent load levels and montor the behavors s wth great potental exercsng market power. In ths paper an ndex has been proposed to detect the nodal potental market power s n LMP system. Ths ndex has been studed n two condtons, frst n constant load and the then n system to consder the load varaton system. By calculatng ths ndex the market operator can montor the s wth hgh potental exercsng market power. In secton 2 some bascs has been explaned to defne proposed ndex. In secton 3 the proposed ndex has been ntroduced and then the proposed ndex has been studed n secton 4 for two test system n two condtons. The proposed ndex has been concludedd n secton 5. 2 Nodal Supplyng Power a Generator By runnng DCOPF the generaton vector generator has been obtaned (pg). To calculate the delvered power a generator to each bus as [5] the below equatons have been appled to the generaton vector pg. Accordng to the Fg. 2 whch represents the nflow power, outflow power, load (pd ) and generaton (pg ) at the bus system, the below equaton can be obtaned: PI = pl j + pg (4) j Ns where pi s the total power nflow nto the bus. The pl j denotes the nflow power from bus j to bus and the number nflows to bus s Ns. The above equaton can be wrtten as below for N node system. pl j PI ( * PI j ) = pg, = 1,2,... N (5) j Ns PI j The matrx form above equaton can be wrtten as: M * PI = Pg (6) 1 j = pl j mj = j Ns (7) PI j otherwse PI = M 1 * Pg (8) where PI s nodal power nflow vector, Pg s nodal generaton vector and M s dstrbuton matrx whch the mth element ths matrx s defned as the above equaton. Fg. 2 A general node n the system. The -th element PI can be wrtten as: 1 PI = [ M ] j * Pgj (9) j Ns The above equaton represent that the contrbuton each system generator n power nflow to bus. The load n bus can be wrtten as below, consderng the Eq. (9). pd pd pd = * PI = 1 pd * [ M ] j * 1 Pg PI PI j N j = *[ M ] j j * Pgj NPI pd 1 = 1 *([ M ] 1 * Pg 1 +... + [ M ] k * Pg k +...) PI (1) Ultmately the k-th element above equaton whchh denotes the each generator contrbuton n load bus can be wrtten as below: pd 1 P gk, = [ M ] k, * P (11) gk PI After runnng DCOPF, the generator delveredd power to each node s load can be obtaned through the above equatons. 3 The Proposed Index to Detect the Potental Market Power under LMP In ths secton an ndex has been ntroduced to detectt the potental Nodal Market Power (NMP) n LMP system. It should be noted that ths ndex detect only the structural potental exercsng market power by a but n real power market a may apply the market power wth ts bd strategy or may not apply market power. It s obvous that a possblty exercsng market power by a wth great potental exercsng market power s hgh. So t s sgnfcant for ISO to dentfy and montor the behavor s wth great potental exercsng market power. The proposed ndex to detect the potental exercsng market power by k at bus system s formulated as below: k kuncons, k p p NMP = (12) d Soabad & Akbar Foroud: Nodal Market Power Detecton under Locatonal Margnal Prcng 47
k where NMP denotes the nodal potental exercsng k market power by k n the bus system. p denotes the generator delvered power at each node after kunc, cons runnng the DCOPF (Eqs. (13)-(17)), and p denotes the generator delvered power at each node after runnng unconstraned DCOPF wthoutt the transmsson constrant. Based on ths ndex the potental nodal market power for k at bus s proporton to the dfference between the generator delvered power to each node between DCOPF and unconstraned DCOPF. Accordng to ths crteron the market power potental exsts f the NMP s greater than zero. More precsely, ths ndex express that the market power potental exst when the generaton ncreasee n ordnary DCOPF n comparson to unconstraned DCOPF. In another word the structural stuaton lke transmsson power lmt cause that the more costly s generaton ncreases. It should be noted thatt t has been assumed that ISO wll know the approxmaton margnal cost generaton unts accordng to ther types and wll run DCOPF by margnal cost unts before real market clearng whch submttng ther bds to ISO. So ths ndex s an ex-antee ndex and more precsely structural ex-antfor market power, whereas behavoral ndces typcally lookng for actual evdence the exercse market power [1]. ndex whch look to fnd the potental Below equaton represent the DCOPF formulaton. Eqs. (16) and (17) n ths ndex denotes that generaton capacty each and transmsson constrant has been consdered ndrectly n proposed ndex trough DCOPF problem. DCOPF problem: GC( P )= a * P + b * P ^2 PG, δ G { mn ( GC ( ))} P G Subject to: PG-PD=P(δ) )=B.*δ Low PG PG P Up G -Tmax H.* *δ Tmax G G (13) ( 14) (15) (16) (17) As expressed prevously n LMP system by ncreasee load, the bus prces at buses have a step change. In snce the step change prces, the opportunty and potental exercsng power market ncrease. So t s sgnfcant for market operator to antcpate the potental market power each s n and montor the behavor s n. The selected test cases to study are PJM 5 bus and 3 bus test case. Fg. 3 showss the dagram PJM 5 bus test case wth generaton and transmsson lmt data. Ths test case has 6 lnes, 3 load buses and 4s at each generaton bus, t means that the two generators at bus 1 consder as a unt. The detal data about ths test case s avalable n [16]. 4.1 Fve Bus Test Case n Condton A In ths condton a system wth the constant load has been analyzed. The DCOPF has been appled to obtan the proposed ndex n secton 3.By runnng DCOPF and unconstraned DCOPF the contrbuton each generator n supplyng power each node has been calculated through Eqs. (4)-(11) for DCOPF and unconstraned DCOPF. Below matrx equaton denotes the contrbuton each system generator n power nflow to node by runnng DCOPF. M 1 * Pg = PI 1..5189 21.5776 1..1676.128.369.327 1..765.6 323.4279 1..7844 1. 466 452.697 318.6853 = 358.3559 455.781 466. The quantty each element M -1 share each generator n power nflow bus. (18) 1 denotes the f each system 4 Studes In ths paper the potental market power studedd n two condtons on two test cases to study the proposed ndex comprehensvely n dfferent condton. The two condtons are: 1- The frst condtonn s analyzng the proposed ndex when load s constant at each bus system. 2- The second condton s detectng market power n dfferent load level system whchh causes the step change n locatonal margnal prces. Fg. 3 The fve bus test system dagram. 48 Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214
The number one n M -1 denotes that the whole generaton a delvers to a determned bus. Followng the above equaton, accordng to Eq. (11) each contrbuton n load supplyng each bus has been calculated and depcted n Table 2. Now the system has been analyzed under unconstraned DCOPF (wthout transmsson constrant). The below matrx equaton denotes the contrbuton each system generator n power nflow to node by runnng unconstraned DCOPF. M 1 * Pg PI = 1..616 21.625 1..3625.1558.554 1..38.277 19.3975 1..8136 1. 6 57.9832 344.53 (19) = 385.122 571.6267 6. Followng the above equaton, accordng to Eq. (11) each contrbuton n load supplyng each bus has been calculated and depcted n Table 3 for unconstraned DCOPF (wthout transmsson constrant). Ultmately by applyng Eq. (12) the nodal market power has been calculated for each at each bus system as depcted n Table 4. Table 2 The share each n load supplyng each bus n DCOPF n 5 bus test case. Nodal supplyng power s A C D E SUM BUS2 112.4 52.9 134.7 3 BUS3 5.7 27.8 23.5 3 BUS4 93 37 4 Table 3 The share each n load supplyng each bus n unconstraned DCOPF n 5 bus test case. Nodal supplyng power s A C D E SUM BUS2 11.4 189.6 3 BUS3 25.4 19 84.5 3 BUS4 74.1 325.9 4 Table 4 The nodal market power (NMP) for each at each system bus n 5 bus test case. NMP NMP2 NMP3 NMP4 A.67-6.57 4.73 C 17.63 26.93 D E -18.3-2.33-4.72 The NMPs whch are greater than zero denote the potental exercsng nodal market power can be exst. Accordng to the results the potental market power exercsng by D s zero n all system buses snce ths generator doesn t partcpate n market n both DCOPF and unconstraned DCOPF. The maxmum NMP belongs to C at bus 3. Ths means C at bus 3 has the great potental exercsng market power. Also E has negatve NMP n all buses and ths has no potental to exercse market power n system. A could have the potental exercsng market power at bus 2, 4 especally at bus 4. 4.2 Fve Bus Test Case n Condton B In ths condton the potental exercsng market power analyzed n the system. Snce n the bus prces have a step change and so the revenues a s have a step change too, t s sgnfcant to detect and montor the behavor s. In ths case the system load change s assumed to be dstrbuted to all bus loads n proporton to ther base case load. Table 5 depcts the fve bus system that cause step change n bus prces. Table 5 The crtcal load levels and the locatonal margnal prces at each bus n 5 bus test case. load (MW) Locatonal Margnal Prces at each system bus [$/h] A B C D E 6 14 14 14 14 14 676.8 14 19.38 21.44 27.13 1 75.2 15 21.72 24.31 31.42 1 717.4 16.98 26.38 3 39.93 1 1171.7 17 26.42 3.4 4 1 14 17 26.42 3.4 4 1 Soabad & Akbar Foroud: Nodal Market Power Detecton under Locatonal Margnal Prcng 49
By runnng DCOPF and unconstraned DCOPF the contrbuton each generator n supplyng power each node has been calculated as Eqs. (4)-(11) n each system. Accordng to case A, the s A & C have the potental exercsng market power n ths system, so n ths case A behavor has been analyzed n the. Results (Table 6) demonstrate that potental market power exercsng changes consderably wth system load varaton. So load varaton n detecton market power can't be neglected. For A the potental market power exercsng at frst ncreases and after a specal load level ths potental decreases, so the load ncrease sometmes decreasess the potental market power exercsng. Also there s a harmony n the NMP all bus system, n another word the NMP buses ncrease together and decrease together. The maxmum potental market power for A occurs when the system load ncreases up to 718 MW at bus 2. As depcted n Fg. 4 between three NMPs, the NMP2 s above all NMPs n most, so the A can exercse market power at bus 2 more than the other system buses. 4.3 3 Bus Test Case n Condton A In ths condton the IEEE 3-Bus test system (Fg. 5) has been analyzed on the constant load at each bus. Ths test case has 6 generators at 6 buses (as depctedd n Table 7) and here each generator consdered as a one and also ths test system has 41 branches. The detal data about ths test case s avalable n [15]. The dagram ths test case has been depcted n Fg. 5. Table 6 The potental nodal market power (NMP) A n n 5 bus test case. A NMP2 NMP3 NMP4 CLL = 677.46.5.12 CLL = 76 15.26 8.2 5.96 CLLL = 718 21.811 11.85 8.76 CLL = 1173.67-6.57 4.73 Fg. 4 The potental nodal market power for A n crtcal load level system (). Fg. 5 The dagram IEEE 3-Bus test system. Table 7 The s locaton n IEEE 3-Bus test system. no 1 2 3 4 5 6 locaton Bus1 Bus2 Bus3 Bus4 Bus5 Bus6 For ths condton the system load s typcallyy equated to 189.2 MW and n ths condton no congeston exsts n the system, so no nodal prce exstss n the system and all buses have the unform prce 3.789 [$/h]. Therefore the proposed ndex to detect the potental market power under nodal prcng has no meanng n ths condton and equated to zero for alll s. 4.4 3 Bus Test Case n Condton B In ths condton the potental exercsng market power analyzed n the the IEEEE 3-Bus testt system. For ths test case the system and nodal prce n each CLL have been depcted n Table A.1 n appendx A. As Table A.1 demonstrates when system load rase from the CLL 253 to CLLL 259, the maxmum change occurs n nodal prces. It should be noted that fve CLL system has been consdered and also n ths condton the system load change s assumed to be dstrbutedd to all bus loads n proporton to ther base case load. By runnng DCOPF and unconstraned DCOPF the contrbuton each generator n supplyng power each node has been calculated by Eqs. (4)-(11) n each IEEE 3-Bus test system. For ths test case the fnal result for CLL 259MW has been depcted n Table 8 and other results for other have been depcted n appendx (Tables A.2-A.4). 5 Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214
Table 8 The potental nodal market power (NMP) s n CLLL 259 MW n IEEE 3-Bus test system. 1 2 3 4 5 6 NMP bus2.6 -.8 bus3 -.2 bus4.6 -.7 bus7.16 -.41.23 bus8. 1 -.21.9 bus1 -. 126 -.163.317.12 -.41 bus12 -.249 -.141.389 bus14 -. 141 -.8.29 -.71 bus15 -.68 -.38.161 -.57 bus16 -.249 -.141.389 bus17 -. 162 -.173.212.169.6 -.54 bus18 -.68 -.38.161 -.57 bus19 -. 19 -.115.11.11.47 -.37 bus2 -. 126 -.163.317.12 -.41 bus21.116.3 -.12 bus23 -.2 bus24.89 -.91 bus26 -.2 bus29 -.2 bus3 -.2 The CLLL 259MW has been chosen because the maxmum nodal prces change occurs n ths CLL. The omtted buses n Table 8 have no load or havng the equal share s n DCOPF and unconstraned DCOPF. In ths test case because greater network and more s, the structural condton system can face the proposed ndex to more challenges and so more conclusons have been obtaned. The postve NMPs n Table 8 denote the exstence potental exercsng nodal market power. As result demonstratess n Table 8, a can have a potental exercsng market power n specal buses. These buses are buses whch are close to a. For nstance 3 can have the potental market power n bus 12 and 14-19 whch are close to 3. Although the vcnty buses to s cause that a have the potental exercsng market power on those buses, but the structure system and also the quantty generaton a n DCOPF problem can create the potental exercsng market power on far buses from a. For nstance 1 and Geco6 have the potental exercsng market power n bus7 whch s almost far away from these s. Ths s due to hgh quantty generaton n 1 and 6 and also the structure power system ncludng the transmsson capacty, load and generaton locaton so on. To analyze the Table 8 n detal, the resultss demonstrate that the NMP for 2 s negatve or zero n all buses (column2) whch denote that ths has no potental to exercse market power n ths system n CLL 259MW. 1 lke 2 has the negatve or zero NMP n most buses system except buses number 2, 4, 7 and 8 (column1). The maxmumm NMP between s belong to 3 n bus 12 and 16 system whch are close to 3, also 3 has the postve NMP n most system buses. 4 lke 3 has the postve NMP n most system busess and the maxmum NMP for ths s seen n busess 1 and 2. s 5and 6 have the postve NMP n some buses and negatve or zero NMP n some other buses but 6 has the negatve NMP n most system buses. Now to study the potental exercsng market power n varous for a, the NMP 3 n varous has been depcted n Fg. 6. 3 has the maxmum NMP between the other s n the CLL 259MW. So ths has been chosen between other s to study the potental exercsng market power n varous. Fg. 6 denotes that n whch CLL the Geco3 can have the more potental exercsng market power. The CLL 261MW and 259MW are desrable load levels for 3 to exercse market power accordng to Fg. 6. Also n the 223 MW, 3 has no potental exercsng market power. From another aspect the Fg. 6 denotes that n whchh buses the Geco3 can have the more potental exercsng market power. In bus1 up to bus1 ths has negatve or zero potental exercsng market power because these buses are approxmately far from ths. In bus12 and 16 n CLLL 261MW 3 has the maxmumm potental exercsng market power whereas n the same busess n 223MW ths has no potental exercsng market power. Fg. 6 The NMP 3 n dfferent system. Soabad & Akbar Foroud: Nodal Market Power Detecton under Locatonal Margnal Prcng 51
Appendx: Table A.1 The crtcal load levels and the locatonal margnal prces at IEEE 3-bus test system. bus1 bus2 LMP @ bus3 bus4 bus5 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.1 4.1 4.1 4.1 4.1 252MW 4.2 4.2 4.21 4.21 4.2 259MW 3.87 3.85 3.91 3.92 3.82 261MW 3.86 3.84 3.9 3.91 3.8 LMP @ bus1 bus2 bus3 bus4 bus5 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.1 4.1 4.1 4.1 4.1 252MW 4.19 4.19 5.88 4.29 4.34 259MW 3.78 3.79 23.49 4.49 4.86 261MW 3.76 3.78 24.65 4.51 4.91 LMP @ bus1 bus2 bus3 bus4 bus5 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.1 4.1 4.1 4.1 4.1 252MW 4.29 4.34 4.34 4.36 4.38 259MW 4.49 4.99 4.99 5.24 5.44 261MW 4.51 5.5 5.5 5.32 5.53 LMP @ bus1 bus2 bus3 bus4 bus5 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.1 4.1 4.1 4.1 4.1 252MW 4.34 4.34 4.37 4.36 4.35 259MW 4.94 4.88 5.24 5.12 5.5 261MW 4.99 4.93 5.31 5.18 5.12 bus1 bus2 LMP @ bus3 bus4 bus5 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.1 4.1 4.1 4.2 4.2 252MW 4.37 4.38 4.35 4.5 4.9 259MW 5.4 5.9 4.4 5.83 8.95 261MW 5.1 5.15 4.39 5.93 9.23 bus26 bus27 bus28 bus29 bus3 19MW 3.79 3.79 3.79 3.79 3.79 223MW 4.2 4 4.1 4 4 252MW 4.9 4.4 4.52 4.4 4.4 259MW 8.95 4.12 7.89 4.12 4.12 261MW 9.23 4.12 8.12 4.12 4.12 Table A.2 The nodal market power s n CLL 223MW n IEEE 3-Bus test system. NMP s n IEEE 3-Bus test system n CLL 223 MW NMP@ bus3 bus4 bus5 bus8 bus9 1 -.4 -.126 -.83 -.39 -.7 2 -.85 -.43 -.58 -.4 3 4 5 6 -.28 -.115 Resumpton NMP s n IEEE 3-Bus test system n CLL 223 MW NMP@ bus11 bus13 bus15 bus16 bus17 1 -.5 -.9.5.6 -.9 2 -.3 -.3.4.4 -.3 3 -.114 -.49 -.19 -.114 4 -.25 5 -.4 -.86 -.116 6 -.88 Resumpton NMP s n IEEE 3-Bus test system n CLL 223 MW NMP@ bus18 bus19 bus2 bus21 bus22 1 -.7.6.4 -.5 2 -.1.4.7 -.3 3 -.27 -.19 -.13 4 -.16 -.5 -.25 -.6 5 -.3 -.116 -.72 -.4 -.9 6 -.71 -.45 -.88 -.111 Resumpton NMP s n IEEE 3-Bus test system n CLL 223 MW NMP@ bus24 bus25 bus27 bus3 1 2 3 4 5 -.126 -.3 6 -.122 -.126 -.126 52 Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214
Table A.3 The nodal market power s n CLL 251 MW n IEEE 3-Bus test system. NMP s n IEEE 3-Bus test system n CLL 251 MW NMP@ 1 2 3 bus2.1 -.1 bus4.1 -.1 bus7.13.16 bus8.51.53 bus1.25.24 bus12 -.38 -.22.6 bus14 -.28 -.16.2 bus15 -.15 -.9.5 bus16 -.38 -.22.6 bus17.15.9.4 bus18 -.15 -.9.5 bus19 -.6 -.9.14 bus2.25.24 bus21 bus24 NMP s n IEEE 3-Bus test system n CLL 251 MW NMP@ 4 5 6 bus2 bus4 bus7 -.29 bus8 -.14 bus1.32.4 -.85 bus12 bus14.24 bus15.2 bus16 bus17.1.3 -.76 bus18.2 bus19 -.6.63 -.56 bus2.32.4 -.85 bus21.92.11 -.13 bus24.91 -.91 5 Concluson In ths paper an ndex has been ntroduced to detect the potental nodal market power exercsng under LMP system. LMP s the result system constrant volaton lke transmsson lmts. So under LMP system the structural stuaton system provde an envronment to exercse market power. Especally n LMP system n some determned load levels, prces buses have a step change. These load levels called. Detectng and montorng the behavor a under s sgnfcant snce the step change bus prces caused step change n revenue n. In ths paper after ntroducng an ndex, ths ndex has been appled n two condtons to two test systems wth small and large network to face the proposed ndex to more challenges and so more conclusons obtaned. In the frst condton the load system s constant and the potental exercsng market power market has been detected for each system. In the second condton the potental market power has been analyzed n crtcal load levels system. Table A.4 The nodal market power s n CLL 261 MW n IEEE 3-Bus test system. NMP s n IEEE 3-Bus test system n CLL 261MW NMP@ 1 2 3 bus2.7 -.7 bus4.7 -.7 bus7.17 -.44 bus8.9 -.24 bus1 -.135 -.172 bus12 -.257 -.145.42 bus14 -.146 -.83.33 bus15 -.7 -.4.169 bus16 -.257 -.145.42 bus17 -.169 -.18.215 bus18 -.7 -.4.169 bus19 -.113 -.12.113 bus2 -.135 -.172 bus21 bus24 NMP@ 4 5 6 bus2 bus4 bus7.27 bus8.16 bus1.339.11 -.43 bus12 bus14 -.74 bus15 -.59 bus16 bus17.183.6 -.55 bus18 -.59 bus19.113.44 -.37 bus2.339.11 -.43 bus21.123.1 -.124 bus24.87 -.87 Soabad & Akbar Foroud: Nodal Market Power Detecton under Locatonal Margnal Prcng 53
Based on results, the structural stuaton system affects the potental market power exercsng. Results demonstrate that the potental market power exercsng consderably vares wth load varaton. Also the load ncrease n system sometmes decreases the potental exercsng market power. References [1] P. Twomey, R. Green, K. Neuhf and D. Newbery, A revew the montorng market power the possble roles TSOs n montorng for market power ssues n congested transmsson systems, Journal Energy Lterature, Vol. 2, pp. 1-56, 25. [2] J. Trole, The Theory Industral Organzaton, Cambrdge, MA: MIT, 1988. [3] W. M. Landes and R. A. Posner, Market Power n Anttrust Cases, Harvard Law Revew, Vol. 94, No. 5, pp. 937-996, 1981. [4] P. Vsudhphan and M. D. Ilc, Dependence Generaton Market Power on the Demand/supply Rato: Analyss and Modelng, Power Engneerng Socety Wnter Meetng Sngapore, Vol. 2, pp.1115-1122, Jan. 2. [5] P. Wang, Y. Xao and Y. Dng, Nodal Market Power Assessment n Electrcty Markets, IEEE Trans. on Power s, Vol. 19, No. 3, pp. 1373-1379, Aug. 24. [6] D. Krschen and G. Strbac, Fundamentals Power Economcs, J. Wley & Sons, Ltd. ISBN: -47-84572-4, 24. [7] S. Salarkhel and A. Akbar Foroud, Market Power Assessment n Electrcty Markets: Supply Functon Equlbrum-based Model, Int. Trans. on Electrcal Energy s, Vol. 23, No. 4, pp. 553-569, May 213. [8] A. Badr, S. Jadd and M. Parsa-Moghaddam, Impact Partcpants market power and Transmsson Constrants on GenCos Nash Equlbrum Pont, Iranan Journal Electrcal and Electronc Engneerng, Vol. 3, No. 1, pp. 1-9, 27. [9] S. Salarkhel, A. Akbar Foroud and R. Keypour, Analyzng Capacty Wthholdng n Olgopoly Electrcty Markets Consderng Forward Contracts and Demand Elastcty, Iranan Journal Electrcal and Electronc Engneerng, Vol. 7, No. 4, pp. 292-31, 211. [1] E. Bompard, T. Huang and W. Lu Market Power Analyss n the Olgopoly Electrcty Markets under Network Constrants. IET Generaton, Transmsson & Dstrbuton, Vol. 4, No. 2, pp. 244-256, 21. [11] G. Bautsta and V. H. Quntanl, Screenng and Mtgaton Exacerbated Market Power due to Fnancal Transmsson Rghts, IEEE Transactons on Power s, Vol. 2, No. 1, pp. 213-222, 25. [12] A. K. Davd and W. Fushuan, Market Power n Electrcty Supply, IEEE Trans. on Energy Converson, Vol. 16, No. 4, pp. 352-36, 21. [13] K. Atkns, J. Chen, V. S. A. Kumar, M. Macauley and A. Marathe, Locatonal Market Power n Network Constraned Markets, Journal Economc Behavor & Organzaton, Vol. 7, No. 1, pp. 416-43, 29. [14] M. R. Baghaypour and A. Akbar Fourod, A New Market Clearng Mechansm, Based on Comprehensve Welfare Allocaton, Consderng Partcpants Optmalty, Effcency and Extent Transmsson Use, Int. Trans. on Electrcal Energy s, Vol. 23, No. 8, pp. 1335-1364, November 213. [15] F. L, Contnues Locatonal Margnal Prce (CLMP), IEEE Trans. on Power s, Vol. 22, No. 4, pp. 1638-1646, 27. [16] PJM Tranng Materals (LMP 11), PJM. [17] M. Alomoush, auctonable Fxed Transmsson Rghts for Congeston Management, Ph.D. Dssertaton, Dept. Elect. Comput. Eng., Inst. Technol., Chcago, IL, May 2. restructurng. Alreza Soabad was born n Tehran, Iran n 1989. He receved BSc degree and M.Sc. degree n electrcal engneerng faculty from Semnan Unversty, Semnan, Iran. Hs research nterests nclude power market and relablty n power system. Asghar Akbar Foroud was born n Hamadan, Iran n 1972. He receved B.Sc. degree from Tehran Unversty and M.Sc. and Ph.D. degrees from Tarbat-modares Unversty, Tehran, Iran. Hs research nterests nclude power system dynamcs, operaton and 54 Iranan Journal Electrcal & Electronc Engneerng, Vol. 1, No. 1, March 214