A Basic Power System Analysis by Using LabVIEW

Transcription

1 38 ACTA ELECTROTEHNCA A Bai Power Sytem Analyi by Uing LabVEW F. BENHAMDA, A. AYAD, A. BENDAOUED and A. BENTAALLAH Abtrat: Thi paper will preent a projet whih i a virtual intrument (V) of everal power ytem analye by uing LabVEW verion 8.5. LabVEW ha been hoen a the main platform of thi projet beaue it i a uer friendly programming language and eay to be learnt by new programmer. Thi projet i deigned to onurrently familiarize the tudent with the ue of LabVEW and with eletrial power ytem. Thi paper will diu deign and development of interative intrutional virtual intrument (V) module to tudy (a) load analyi, (b) ingle phae iruit, () Three-phae eletrial power generation by Delta and Wye generator with ombination of Wye and Delta load. Both balaned and unbalaned load are imulated. Uing V module, a viual demontration ha been reated that how the reulting onequene of what our when balaned load beome unbalaned, (d) and finally modeling of tranmiion line (hort, medium and long model). Thi projet i hopefully an ait tudent and leturer in their learning and teahing. Keyword: Power ytem analyi, LabVEW oftware, virtual ntrument, eduational virtual laboratory. 1. NTRODUCTON Beaue of the reent advane in omputer and tehnologie, the omplexity in all area of the eletrial power indutry (generation, tranmiion, ditribution, ontrol, et.) ha inreaed, and the graduate of engineering and tehnology mut be welltrained to addre the need of the indutry. To addre thi need, mot of the engineering program and ome of the engineering tehnology program have introdued oure, program, and laboratorie in power ytem to provide the graduate with the theoretial and pratial knowledge, a well a experiene. The tudy of eletrial power ytem require a good bakground on advaned mathemati, and ine mot of the engineering tehnology program do not require advaned mathemati, it i diffiult to teah eletrial power ytem in thee program. To deal with thi ubjet, many text driven oftware program are urrently ued in univerity to deign and analyze different ytem. A good example of uh program i Matlab oftware. With the advent of objet-oriented programming, we have now program that are interative and uer-friendly. Uing uh omputer program allow tudent to pend le time writing the ode to olve a problem and pend more time undertanding the onept. A example of uh program i LabVEW oftware whih i a graphial programming environment and i baed on the onept of data flow programming. Originally deigned for tet and meaurement appliation, the program ha been modified over the lat 15 year to deign and analyze variou omplex ytem. t i Manuript reeived February 05, widely aepted by indutry, univerity, and reearh laboratorie around the world a a tandard for data aquiition (DAQ) and intrument ontrol oftware [1]. Uer of LabVEW an build intrumentation alled virtual intrument (V) uing oftware objet. With proper hardware, thee V an be ued for remote data aquiition, analyi, deign, and ditributed ontrol. The built-in library of LabVEW ha a number of V that an be ued to deign and develop any ytem. LabVEW an be ued to addre the need of variou oure in a tehnology and iene program [2] [3] [4] [5] [10] and [11]. The objetive of thi paper i to diu the appliation of built-in V in LabVEW to develop V module for ue in eletrial power ytem oure. 2. APPLCATON AREAS OF LABVEW LabVEW i extremely flexible and ome of the appliation area of LabVEW [5] are Simulation, Data Aquiition, and Data Proeing. The Data Proeing library inlude ignal generation, digital ignal proeing (DSP), meaurement, filter, window, urve fitting, probability and tatiti, linear algebra, numerial method, intrument ontrol, program development, ontrol ytem, and fuzzy logi. Thee feature of LabVEW will help provide an interdiiplinary, integrated teahing and learning experiene that integrate team-oriented, hand-on learning experiene throughout the engineering tehnology and iene program, engaging tudent in the deign and analyi proe beginning with their firt year. LabVEW an ommand DAQ board to read analog input ignal (A/D onverion), generate analog output ignal (D/A onverion), read and write digital 2011 Mediamira Siene Publiher. All right reerved.

2 Volume 52, Number 1, ignal, and manipulate the on-board ounter for frequeny meaurement, pule generation, et. The voltage data goe into the plug-in DAQ board in the omputer, whih end data into omputer memory for torage, proeing, or other manipulation. 3. SYSTEM LOAD ANALYSS Generally, the power ytem load an be divided into indutrial, ommerial and reidential. 'the greatet value of load during a 24-hour period i alled the peak or maximum demand'. The load fator whih i defined a the ratio of average load over a deignated period of time to the peak load ourring in that period ha been introdued in order to ae the uefulne of the generating plant. The load fator may be alulated for a day, a month or a year, o, in our analyi eah of thee three ettlement period ha been taken into aount for the analyi. Therefore, the name of the V for thi analyi ha been given a Sytem Load Analyi. The Sytem Load Analyi V ha been developed with everal feature of input and output. The front panel of the daily ytem load analyi V i hown in Fig SNGLE PHASE (V ) MODULE The tudy of eletri power ytem require a good undertanding of ingle phae and three phae iruit, and oure in eletri iruit and eletri mahine are uually the prerequiite oure, among other, for the introdutory power ytem oure. Almot every introdutory eletri power ytem text provide a brief overview of eletri iruit, and the intrutor pend one to two week of their leture time reviewing eletri iruit. Depending upon the tudent demographi, the intrutor may pend more time diuing thee topi. Ue of program to diplay waveform of voltage, urrent, and power are ommon in the tudy of eletri power ytem beaue their ue enhane the intrution proe and tudent omprehenion. The V module preented below are developed to ait tudent in thi proe Power in Single-Phae AC Ciruit The equation ued in thi V are the following: v( t) V o( t ) (1) m v i( t) o ( t ) (2) m i p( t) v( t) i( t) (3) Where: v(t) i the intantaneou voltage. V m = maximum value of the voltage, θ v = angle of voltage in degree, i(t) = intantaneou urrent, m = maximum value of the urrent, θ i = angle of urrent in degree and p(t) = intantaneou power. The other equation that are ued in thi V are equation to alulate the rm value of voltage and urrent, the maximum value of urrent from voltage and impedane information, and the real power (P), reative power (Q), total power (S) and the per unit quantitie. Vm m V, (4) 2 2 m Vm V Z Z (5) P V o, Q V in, S P jq (6) Where: V i the rm value of voltage and i the rm value of urrent. For the ytem per unit value the following equation are ued in thi V. V ( V ) / V (7) pu V V bae ( ) / (8) pu bae Z V V S (9) 2 bae bae / bae bae / bae S (( V ) / V ) (( ) / ) (10) pu S V bae bae The ubript pu indiate per-unit value. Fig. 1. Front panel and output waveform for the daily ytem load analyi V.

3 40 ACTA ELECTROTEHNCA The front panel of thi V onit of (a) the uer input (ontrol) uh a maximum voltage, angle of the voltage, voltage bae, MVA bae, impedane, angle of the impedane, frequeny and graph ontrol, (b) the diplay (indiator) uh a P, Q, S, and graph uh a v(t) and i(t), p(t) and phaor diagram in ytem per unit. Fig. 2.a. Uer nput of the ingle phae module. Thi V wa imulated with the input value from an example in [6], and the reult from the V mathed with the example reult. The front panel of thi V i hown in figure 2 (figure 2.a Uer nput, and figure 2.b V Output reult and phaor diagram). 5. THREE PHASE CRCUTS (V) MODULE V were developed uing the equation from [6] [7] and [8]. Thee are tandard three phae equation whih an be found in any eletri iruit and/or eletri power ytem book. Thi V imulated both the Delta and Star onnetion and alulated the line parameter and total power from the given phae parameter and how the phaor diagram of voltage and urrent of both ending and reeiving end. The Star/Delta V wa imulated with input value from example in [6] [7], and the reult mathed the example reult. The front panel of thi V onited of ontrol for uer input of phae parameter and load information and indiator to diplay alulated parameter. The diagram panel imulated variou equation through the ue of built-in arithmeti ion and other ion to deal with omplex notation. t onited of variou ae truture and tab ontrol to deide between the type of onnetion, the S or per unit ytem, the type of ytem (balaned or unbalaned) and to deide if the neutral i joined or not joined. The front panel of thi V indiating the imulation reult of the Star onnetion i hown. The three phae voltage V [8] i deigned to demontrate the voltage relationhip in Star/Star onnetion. The diagram panel of thi V i large and diffiult to fit on a tandard ize paper. A a reult, we are preenting the front panel of thi V in figure 3.a, 3.b et 3. below. To ondut variou analye, the oure and load mut be of ame type (Star/Star or Delta/Delta). However, ometime the oure and load may not be of the ame onnetion type, and a tranformation mut be arried out to onvert both the load and oure to the ame type uing tandard equation. figure 2.a preent the uer input (oure and load ontrol), the imulation reult are preented in figure 3.b, 3. and 3.d, figure 3.b preent the V output (voltage graph with ontrol), phaor diagram of oure and load urrent and Fig. 2.b. V Output reult and phaor diagram.

4 Volume 52, Number 1, analyi, a the parameter of the line (erie apaitane, hunt apaitane, indutane, and reitane) are uniformly ditributed over the length of the line. The exat analyi i ompliated and time onuming. Fortunately, depending on the length of the line, ome of thee parameter an be lumped, reulting in a implified model with reaonably aurate reult. Fig. 3.a. V uer input (oure and load ontrol) Short Tranmiion Line Model f the length of the line (l) i le than or equal to 80 km, then a hort tranmiion line model i ued for analyi [7] a hown in figure 3. n thi type of modeling, the apaitane have negligible effet, and they are ignored. The reitane and indutane are lumped and repreented by ingle unit. The per-phae model of the line i baially a erie iruit with a muh impler voltage, urrent, and power equation. figure 4 repreent the diagram of uh a line. Z V V S R Fig. 3.b. V output (phaor diagram of oure and load urrent and voltage). Fig. 3.. Front Panel reult of Balaned Three Phae (Star/Delta) Ciruit V. voltage are preented in figure 3., figure 3.d preent front panel reult of balaned three phae (Star/Delta) Ciruit. 6. TRANSMSSON LNE ( V) MODULE One of the requirement of the operation of any power ytem i the maintenane of the voltage within peified limit at variou point in the ytem [7]. Thi require undertanding the mathematial model of the tranmiion line and olution of variou equation ued to alulate voltage, urrent, and power at variou point of a tranmiion line. The exat analyi of the tranmiion line involve a ditributed parameter The line equation are a follow [6]: Z ( r jl) l R jx (11) S V (12) R R(3 ) /3 R VS VR Z R (13) S (14) R VR(%) ( ( V V ) / V ) 100 (15) S S (3 ) 3 VR R R( NL) R( FL) R( FL) (16) S S S (17) L(3 ) S(3 ) R(3 ) ( P / P ) 100 (18) R(3 ) S(3 ) Where: Z i the total line impedane, l i the line length, R i the reeiving end urrent, V i the voltage at the ending end, i the urrent at the reeiving end, VR(%) i the perentage voltage regulation, SL(3 i ) the ending end power, P jq, SL(3 ) i the total line lo and i the tranmiion line effiieny. The voltage and urrent equation of the hort tranmiion line model i a follow [7]: V AV B R R CV C R R or in matrix form Fig. 4. Short tranmiion line model. V A B VR V 1 Z VR C D R 0 1 R (19) (20)

5 42 ACTA ELECTROTEHNCA 6.2. Medium Tranmiion Line f the length of the line i greater than 80 km and le than or equal to 240 km, then a medium tranmiion line model i ued for analyi [7] a hown in figure 4. n thi type of modeling, the hunt admittane, uually pure apaitane, i inluded in the alulation. f the total hunt apaitane i divided into equal part plaed at the ending end and reeiving end of the line, the iruit i alled a nominal π. On the other hand, if all of the hunt admittane of the line i lumped in the hunt arm of the T and the erie impedane i divided equally between the two erie arm reult in the nominal T, the per-phae model of the line i baially a erie-parallel iruit with impler voltage, urrent, and power equation. Figure 5 repreent the nominal π model of uh a line. V The voltage and urrent equation of the nominal π model i a follow [7]: V (1 ZY / 2) V Z R R Y(1 ZY / 4) V (1 ZY / 2) R R Or in matrix form V A BVR C D R V (1 ZY / 2) Z VR Y (1 ZY / 4) (1 ZY / 2) R 6.3. Long Tranmiion Line Model (21) (22) The exat olution of any tranmiion line and one required for a high degree of auray in alulating of line more than approximately 240 km long mut onider the fat that the parameter of the line are not lumped but are ditributed uniformly throughout the line [6]. The per phae iruit of thi line i hown in figure 6. V S S The hyperboli form of voltage and urrent equation for thi line are [6]: Z Fig. 5. Nominal π model of a medium tranmiion line. Z Fig. 6. Long tranmiion line model. R R V R S R V R S R With: V A BVR C D R V (1 Z ' Y '/ 2) Z ' VR Y '(1 Z ' Y '/ 4) (1 Z ' Y '/ 2) R A oh l, B Z inh l C (1/ Z ) inh l, D oh l Z ' Z inh l Z(inh l) / ( l) Y '/ 2 (1 / Z ) tanh( l / 2) ( Y / 2)(tanh ( l 2)) / ( l 2) (23) (24) (25) Where: Z (= z l ) i the total erie impedane (Ω), Y(=yl ) i the total hunt admittane (Siemen), z i the erie impedane per length unit (Ω/m), y i the hunt admittane per length unit (Siemen/m). and: zy : propagation ontant (26) Z z / y : line harateriti impedane (27) A V i developed uing the previou equation for tranmiion line in one front panel. The hort tranmiion line i deteted automatially if the hunt admittane i equal to zero, ele the uer an deide between the medium or long tranmiion line uing a button from the front panel, whih i ahieved uing ae truture. The V were imulated with the input value from a medium tranmiion line example [9], and the reult from the V mathed with the example reult. The front panel for the medium tranmiion line imulation i hown in figure 7.a and figure 7.b, figure 7.a preent the uer input (line parameter and load ontrol), the imulation reult are preented in figure 7.b. 7. CONCLUSON n thi paper we have diued deign and development of interative intrutional virtual intrument (V) module for tudying (a) load analyi, (b) ingle phae iruit with leading and lagging power fator, () Three-phae eletrial power generation and (d) modeling of tranmiion line. The V module preented in thi paper are teted with the input value from variou example in textbook and reult mathed with the reult of the example. The module preented in thi paper are developed uing implified model. Although thi i uffiient for introduing the onept, elaborate model mut be inorporated into the module to addre the omplex real world ituation. LabVEW ha feature and built-in virtual intrument module idential to mot of the feature found in all thee oftware pakage. LabVEW provide a graphial environment to olve omplex problem. No or minimal programming knowledge i neeary to

6 Volume 52, Number 1, Fig. 7.a. The uer input front panel for the medium tranmiion line imulation V. Fig. 8.b. the imulation reult front panel for the medium tranmiion line imulation V. deign and develop the V module. LabVEW ha proviion to tranfer data between LabVEW, Exel, and MATLAB and all MATLAB and Exel from the LabVEW environment. Therefore, one an ue LabVEW to addre the need of variou oure. Thi will be benefiial for tudent and faulty and introdue tandardization aro the iene program. REFERENCES 1. M. Chugani, A. Samant and N. Cerna, LabVEW Signal Proeing, Prentie Hall, NJ 07458, J.A. Anderon, R.B. Korrapati, and N.K. Swain, Digital ignal proeing uing virtual intrumentation, Pro. of SPE, vol. 4052, Orlando, FL, USA, April 2000, pp

7 44 ACTA ELECTROTEHNCA 3. R.B. Korrapati and N.K. Swain, Study of Modulation Uing Virtual ntrument, Proeeding of Aademy of nformation and Management Siene, vol. 4, no. 1, National onferene on allied aademie, Spring N.K. Swain, J.A. Anderon and R.B. Korrapati, Computerbaed Virtual Engineering Laboratory (CBVEL) and Engineering Tehnology Eduation, annual ASEE onf. pro., New Orlean, Louiiana, USA, L. Well and J. Travi, LabVEW for Everyone, Graphial Programming Even Made Eaier, Prentie Hall, NJ 07458, H. Saadat, Power Sytem Analyi, Prentie Hall, NJ, W.D. Stevenon, Element of Power Sytem Analyi, MGraw-Hill, NY, N. Ertugrul, LabVEW for Eletri Ciruit, Mahine, Drive, and Laboratorie, Prentie Hall, NJ, A.R. Bergen, Power Sytem Analyi, Prentie Hall, NJ, R. Peen, M. Salim and A. Zora, A LabView Baed ntrumentation Sytem for a Wind-Solar Hybrid Power Station, Journal of ndutrial Tehnology, vol. 20, no. 3, pp. 2-8, June-Augut J. Viniiu and S. Ovaldo Uing LabVEW in a Mini Power Sytem Model Allowing Remote Ae and New mplementation, ntern. onf. on engin. Edu., Coimbra Portugal, 3 to 7 September 2007, pp F. Benhamida, A Hybrid Bietion-Hopfield Neural Network Approah to Eonomi Dipath problem with tranmiion loe, Advanement of modelling and imulation tehnique in enterprie, AMSE, Advane B -2007, vol. 50 no. 3, pp, 65-77, Frane, F. Benhamida, A. Bendaoud, A New Formulation of Dynami Eonomi Dipath uing a Hopfield Neural Network, Advanement of modelling and imulation tehnique in enterprie, AMSE, Modeling A -2009, vol. 82 no. 2, pp, 12-26, 2009, Frane. 14. F. Benhamida, A. Bendaoued, A. Bentaallah, A. Ayad, A Hopfield Approah to Eonomi Dipath inluding tranmiion loe Uing Labview Software, Advanement of modelling and imulation tehnique in enterprie, AMSE, Modeling 2D in pre, Frane. Ait.Prof. Farid BENHAMDA Ait.Prof. A. AYAD Ait.Prof. A. BENDAOUED Ait.Prof. A. BENTAALLAH RECOM Laboratory Department of Eletrial Engineering Univerity of Djillali Liabe 22000, Sidi Bel Abbe, Algeria. Phone: farid.benhamida@yahoo.fr F. Benhamida reeived the B.S. degree from Djilali Liabe Univerity, Sidi Bel Abbe, Algeria, in 1999, the M.S. degree from Univerity of tehnology, Bagdad, raq, in 2003, and the Ph.D. degree from Alexandria Univerity, Alexandria, Egypt, in 2006, all in eletrial engineering. Preently, he i an Aitant Profeor in the Eletrial Engineering Department and a Reearh Sientit in the RECOM laboratory (Laboratoire nteration réeaux életrique Convertieur Mahine). Field of interet: Power ytem analyi, Computer aided power ytem; unit ommitment, eonomi dipath. A. Abdelghani wa born in Sidi Bel- Abbe, Algeria. He reeived the B.S. and M.S. degree in eletrial engineering from the Univerity of Djillali Liabe, Sidi Bel-Abbe, in 1995 and 2003, repetively. He reeived hi Ph.D. degree in eletrial engineering from the Univerity of Djillali Liabe, Sidi Bel-Abbe in He i now an Aitant Profeor in the Department of Eletrial Engineering at the Univerity of Djillali Liabe. A. Bendaoud wa born in Oujda, Moroo, in He reeived the Eng.degree in Eletrial Engineering from Univerity of Siene and Tehnology, Oran Algeria, in 1982, the MS degree in 1999 and the Dotorate degree in 2004 from the Eletrial Engineering ntitute of Sidi Bel Abbe Univerity, Algeria. Sine 1994, he work a an Aitant Profeor at Eletrial Engineering Department, Univerity of Sidi Bel Abbe, Algeria. He i a member in RECOM Laboratory. A. Bentaallah: wa born in Sidi Bel- Abbe (Algeria) in 1965; He reeived hi BS degree in Eletrial ingeneering from Sidi Bel-Abbe Univerity (Algeria) in 1991, the MS degree from the ame Univerity in 2005 and the PhD degree from The Eletrial Engeneering ntitute of Univerity of Sidi Bel-Abbe (Algeria) in He i urrently an Aitant Profeor of eletrial engineering in thi Univerity. He i a member in (RECOM).