Performance Improvement of Harmonic Detection using Synchronous Reference Frame Method

Transcription

1 Latet Tren on rt, Sytem an Sgnal Performance Improvement of Harmonc Detecton ung Synchronou eference rame Metho P. Santprapan an K-L. Areerak* Abtract Th paper preent the performance mprovement of harmonc etecton ung a ynchronou reference frame metho S. Th metho ue wth hunt actve power flter to elmnate the harmonc n three-phae power ytem. The toff freuency tunng of low pa an hgh pa flter nclue n the proce of S metho. The hunt actve power flter moel can be repreente by the eal rrent ource. Th moel ue for tetng the performance of harmonc elmnaton. In th paper, the threephae oe rectfer behave a the nonlnear loa to generate the harmonc of the ytem. The mulaton reult an on are ecrbe n th paper. Keywor harmonc etecton, ynchronou reference frame, hunt actve power flter. N I. INTODUTION owaay, nonlnear loa are wely ue n nutre. Thee loa manly generate the harmonc nto the power ytem. Thee harmonc caue a lot of avantage uch a the erroneou meaurement of electrc meter []-[], protectve evce falure [], lo n tranmon lne an electrc evce, an hort-lfe electronc eupment [4]. Therefore, t erouly to mtgate or elmnate the harmonc n the ytem. The one of harmonc elmnaton metho the hunt actve power flter SAP a hown n g.. The SAP prove hgher effcency an more flexble compare wth a hunt pave power flter SAP. Moreover, the ue of SAP can avo the reonance conton n the ytem. In g., the three-phae brge rectfer wth the retve loa k Ω behave a a nonlnear loa n the power ytem. The ynchronou reference frame S metho [5] ue for a harmonc etecton to callate the reference rrent * * *,, for the SAP. The eal rrent ource ue to repreent the SAP to perfectly nject the compenatng The author are wth the Power Qualty eearch Unt, School of Electrcal Engneerng, Suranaree Unverty of Technology SUT, Nakhon atchama, Thalan. The fnancal upport from SUT an Offce of the Natonal eearch ouncl of Thalan are greatly acknowlege. orreponence: kongpol@ut.ac.th rrent,, nto the power ytem. The compenatng rrent are eual to the reference rrent becaue of ung the eal rrent ource moel for SAP. The man objectve n th paper the performance mprovement of the S metho to perfectly etect the harmonc n the ytem. The toff freuency tunng of the flter n the S harmonc etecton proce the man approach to mprove the performance. The performance nex of th approach %THD after compenate. The paper tructure a follow. The revew of the S harmonc etecton metho aree n ecton II. The performance mprovement of the S metho an the mulaton reult are fully preente n ecton III an ecton IV, repectvely. nally, ecton V the concluon of th paper. II. THE EVIEW O THE SYNHONOUS EEENE AME METHOD The harmonc etecton ung the ynchronou reference frame S metho ue to callate the reference rrent * * *,, for the SAP. The proceure of S callaton howe n g.. The g. how that there are four tep to callate the reference rrent for S metho. The frt tep, three phae harmonc rrent,, are tranforme Lu Lv Lw to the pace vector rrent on the frame by ung euaton n block number. After that n the econ tep, only the rrent on an axe are tranforme to the ynchronouly rotatng frame, by ung euaton n block number where ω the funamental freuency of the ytem. The rrent vector on frame are rotate wth ω angular pee a hown n g.. The an from the econ tep are eparate nto two part a hown n euaton an, repectvely. = + = + ISSN: ISBN:

2 Latet Tren on rt, Sytem an Sgnal u L Lu v L Lv w L Lw 8V - Phae L-L, 5Hz Lu Lv Lw * * * Lu g. The power ytem wth a three-phae oe rectfer repreentng a nonlnear loa Lv Lw o = * * * h h co ωt = n ωt = co ωt = n ωt h n ωt co ωt n ωt co ωt h Lu Lv Lw h h g. The block agram for S callaton v w ωt g. The rrent vector on frame The an are the rrent n a c component part, whle the an are the rrent n an ac component part. The c an ac component part mean that the funamental component an the harmonc component, repectvely. In th paper, the eparaton of the funamental component an the harmonc component ue the analog flter uch a low pa flter LP or hgh pa flter HP. In cae of HP, th flter raw the harmonc component out of the rrent on ax an ax a hown n g. 4. However, g. 5 how the ue of LP to raw the funamental component from the rrent on an. In LP cae, the harmonc component can be obtane from ubtractng between the total rrent, on ω u ax an the funamental component. After that, an are tranforme to the pace vector rrent h, h agan by ung euaton n block number. nally, h h an are tranforme to the three-phae reference * * * rrent,, for the SAP by ung euaton n block number 4. Thee reference rrent are ue for the SAP to generate the compenatng rrent nto the power ytem for harmonc elmnaton. ISSN: ISBN:

3 Latet Tren on rt, Sytem an Sgnal g. 4 The ue of HP for the S callaton III. THE PEOMANE IMPOVEMENT O THE S METHOD The toff freuency tunng of the HP an LP n the S callaton proce bae on the eal rrent ource SAP the man approach n th paper to mprove the performance of S harmonc etecton metho. The performance nex of the S mprovement %THD average %THD av, th value can be callate by euaton. k= u, v, w % THD % THD av = There are three type of HP. The frt, econ, an thr orer HP crt an tranfer functon are hown n Table I. k g. 5 The ue of LP for the S callaton TABLE I THE IUIT AND TANSE UNTION O HP The type of HP rt Tranfer functon H rt orer V H = + + Secon orer V H = Thr orer V H = ISSN: ISBN:

4 Latet Tren on rt, Sytem an Sgnal The toff freuency f of thee flter are tune from Hz to Hz an the f value can be callate by: 5 t orer n orer r orer f = 4 π The f tunng n the S proceure ue for tetng by mulaton. The ytem for mulaton hown n g.. The mulaton reult of the ytem n g. wth the tunng f of HP are epcte n g. 6. rom g. 6, the econ orer HP wth f eual to Hz can prove the mnmum %THD av.666%. It mean that th toff freuency value obtan the bet performance for HP. %THD av % toff freuency Hz g. 6 The performance mprovement reult ung HP Smlarly, there are three type of LP. The frt, econ, an thr orer LP crt an tranfer functon are epcte n Table II. TABLE II THE IUIT AND TANSE UNTION O LP The type of LP rt Tranfer functon L rt orer V L = + + Secon orer V L = Thr orer V L = ISSN: ISBN:

5 Latet Tren on rt, Sytem an Sgnal %THD av 5 5.6% t orer n orer r orer Hz hown n g. 8. The g. 9 how the mulaton reult of the ytem ung the thr orer LP wth the toff freuency eual to 56 Hz. rom g. 8 an 9, the compenatng rrent from SAP nject nto the ytem at t=.4. After that the ource rrent are nearly nuoal waveform. The %THD av of thee rrent are eual to.666% ung HP an.6% ung LP, whle %THD before compenaton 4.8%. Thee reult are hown n Table III toff freuency Hz g. 7 The performance mprovement reult ung LP The toff freuency tunng value an the euaton for callate th value the ame a the cae of HP. The mulaton reult of the ytem n g. ung LP are hown n g. 7. It can be een that the thr orer LP wth 56 Hz toff freuency can prove the bet performance %THD av =.6%. IV. SIMULATION ESULTS AND DISSUSSION The mulaton reult of the ytem n g. ung the econ orer HP wth fxe the toff freuency value to TABLE III %THD of the ource rrent before an after compenaton phae %THD of the ource rrent %THD before compenaton %THD after compenaton HP n orer, f c =Hz LP r orer, f c =56 Hz u v w %THD av V u Lu u tme g. 8 The mulaton reult ung HP phae u ISSN: ISBN:

6 Latet Tren on rt, Sytem an Sgnal 5 V u Lu u tme g. 9 The mulaton reult ung LP phae u rom the table III, %THD before compenaton not atfe uner IEEE St [4], whle %THD after compenaton for the both cae can follow on th tanar. Moreover, the ue of LP n the S proceure can prove the maller %THD compare wth the HP. Therefore, the thr orer LP wth fxe the toff freuency to 56 Hz electe for the S harmonc etecton callaton. [5] B. Zhang, The Metho bae on a eneralze k oornate Tranform for urrent Detecton of an Actve Power lter an Power Sytem, IEEE Power Electronc Specalt onference, 7, pp V. ONLUSION Th paper preent the ea for performance mprovement of the harmonc etecton metho calle the ynchronou reference frame S metho. The reult confrm that the ue of LP n the S proce can prove the goo performance for harmonc elmnaton. The LP the thr orer an the toff freuency et to 56 Hz. Moreover, %THD of the ource rrent after compenaton alo atfe uner IEEE St EEENES [] Inrajt P. an Paul J.S., Effect of Harmonc on Power Meaurement, IEEE Petroleum an hemcal Inutry onference, 989, pp. 9. [] Elham B.M., larence L.W., an Aly A.., A Harmonc Analy of the Inucton Watthour Meter egtraton Error, IEEE Tranacton on Power Delvery, vol. 7, no., 99, pp [] Ho J.M., Lu.., The Effect of Harmonc on Dfferental elay for a Tranformer, IEEE Internatonal onference an Exhbton on Electrcty Dtrbuton IED, vol.,. [4] IEEE St , IEEE ecommene practce an reurement for harmonc control n electrcal power ytem. ISSN: ISBN: