Ukhuseleko lomahluko weTransformer kunye nezinye iimveliso zokhuseleko lomahluko | CANWIN

Ukongeza, kukho iimeko ezininzi ezingaqhelekanga zokusebenza kwe-transformer, ikakhulu kuquka inqanaba eliphantsi leoyile, ubushushu okanye uxinzelelo lweoyile oluphezulu, i-voltage ephezulu ye-transformer engathathi cala, ukugqithisa, umbane ogqithisileyo, ukukhupha umoya kakhulu, njl.

Ukuze sijonge iimpazamo ezahlukeneyo okanye iimeko zokusebenza ezingaqhelekanga, simisele ukhuselo olwahlukeneyo, olwahlulwe lwaba lukhuselo oluphambili kunye nokhuselo olungasemva, kwaye ukhuselo oluphambili luneempawu zesenzo esikhawulezayo.

Icandelo 2: Ukhuseleko lokwahluka

Ukhuselo lomahluko olude lolunye lwezona zikhuselo ziphambili ze-transformer, kwaye ukhuseleko lusebenza ngoko nangoko ukuze luthintele iiswitshi kwicala ngalinye. Indawo yokhuseleko yinxalenye ephakathi kwee-transformers zangoku kwicala ngalinye lokhuseleko lomahluko, kubandakanya umzimba we-transformer, imigca yokuphuma phakathi kwe-transformer yangoku kunye ne-transformer. Ngo-2017, i-arrester kwicala le-35kV le-transformer ephambili yeNombolo 2 ye-substation ye-220kV yayine-AB phase flashover, kwaye i-chassis ye-arrester yaphulwa yi-discharge; kuba i-arrester ye-35kV yayiphakathi kwe-rheological transformer kunye ne-transformer ephambili kwicala eliphantsi le-transformer ephambili, yayingaphakathi koluhlu lokhuselo lomahluko olude. Iiseti ezimbini ze-main transformer protections zonke zisebenze ngokuchanekileyo, kwaye impazamo yahlukaniswa.

01

Ingqiqo esisiseko yokukhusela umahluko

Ukhuselo lokwahluka olude lwe-transformer olukhoyo lusebenzisa isixhobo sokukhusela i-microcomputer, kwaye umbane wesigaba ngasinye ungena kwisixhobo sokukhusela ngokwahlukeneyo, kwaye ukhuseleko lokwahluka olude luqatshelwa yi-algorithm yesoftware. Sithatha isigaba esinye njengomzekelo ukubonisa umgaqo osisiseko wokhuseleko lokwahluka olude.

I-differential current "felt" yisixhobo esikhuselayo yi-vector sum ye-secondary currents yee-coils ezimbini. Njengoko kubonisiwe kuMfanekiso 1, xa inkqubo isebenza ngokuqhelekileyo okanye i-short-circuit ngaphandle, i-secondary currents yee-coils ezimbini ziyafana ngobukhulu kwaye zichasene ne-polarity, kwaye i-differential current yi-0, kwaye ukhuseleko alusebenzi ngeli xesha. Njengoko kubonisiwe kuMfanekiso 2, xa kwenzeka impazamo yomhlaba ngaphakathi koluhlu lokhuseleko, i-secondary currents ilingana ngobukhulu kunye ne-polarity, kwaye i-differential current sisiphumo se-secondary currents. Xa ixabiso lokuqalisa umahluko lifikelelwe, ukhuseleko luyasebenza.

Ngokusekelwe kwindlela yokudibanisa i-rheological secondary coil engentla, ukhuselo lokwahlukana olude longeza uhlengahlengiso lwesigaba, ukucinywa kombane olandelanayo, kunye nokuguqulwa kwe-amplitude kwiivektha zangoku kumacala ahlukeneyo ukwenza indlela yokubala yombane ohlukileyo, uze emva koko ufake i-ratio braking characteristic curve. Yenza i-logic esisiseko yokukhusela.

Ukuthatha intambo ye-YN-d11 njengomzekelo, umzobo wentambo kunye nomzobo we-phasor wangoku uboniswe kuMfanekiso 3. Kuyabonakala ukuba ngenxa yokuba kukho umahluko we-angle ye-30° phakathi kwe-phasors esecaleni ephezulu nesezantsi, i-vector sum ye-currents ezimbini ayingo-0 ngexesha lokusebenza okuqhelekileyo, kwaye ukuguqulwa kwesigaba kuyadingeka kuqala. Emva kokuguqulwa, amacala aphezulu naphantsi esigaba esinye anesigaba esifanayo.

Kukho iindlela ezimbini zokuguqula isigaba, enye isekelwe kwicala le-Y, ukuze isigaba sangoku secala le-d sihambelane nesigaba sangoku secala le-Y, esibizwa ngokuba yi-"angle star", ukhuseleko lweenkwenkwezi zecala oluqhelekileyo yiNarui Jibao RCS-978 njl., ifomyula yokuguqula yile:

Enye isekelwe kwicala lika-d, ukuze isigaba sangoku secala lika-Y sihambelane neso secala lika-d, esibizwa ngokuba yi-"star rotation angle". Uninzi lwezixhobo zokukhusela ezikhoyo zisebenzisa indlela ye-star rotation angle, kwaye ifomyula yokuguqula yile:

Injongo yokususwa komsinga we-zero-sequence kukuthintela ukusetyenziswa gwenxa kokhuseleko lomahluko we-longitudinal. Kwi-YN-d wiring, xa kwenzeka impazamo yomhlaba ngaphandle kwecala le-high-voltage, umsinga we-zero-sequence uhamba kwicala le-Y elinombane ophezulu, kodwa akukho msinga we-zero-sequence kwicala le-low-voltage d, kwaye umsinga we-zero-sequence kumacala omabini awunakulinganiswa, ngoko ke ukhuseleko lomahluko aluyi kungasebenzi kakuhle. Kwimo yokuguqula "i-star rotation angle", umahluko phakathi kwemisinga emibini emva kokutshintsha kwesigaba kwicala le-Y ucofe umsinga we-zero, ngoko ke akukho manyathelo afunekayo okuthathwa. Kwimo yokuguqula "i-angle-to-star", imbuyekezo yomsinga we-zero-sequence yenziwa kwi-Y-side current vector, kwaye ifomula yembuyekezo yile:

Ngenxa yomahluko kumlinganiselo wotshintsho lwe-transformer kunye nomlinganiselo wotshintsho lwe-rheological kwicala ngalinye, i-amplitude yesibini yomsinga ohlukeneyo kwicala ngalinye le-transformer ayinakufana ngexesha lokusebenza okuqhelekileyo okanye isiphene sangaphandle. Ngeli xesha, kuyimfuneko ukwenza ukuguqulwa kwe-amplitude, uthathe ixabiso langoku kwelinye icala njengesalathiso, ubale i-balance coefficient kwelinye icala ngokwe-voltage kumacala omabini kunye ne-rheological ratio, kwaye uphindaphinde i-current kwelinye icala nge-balance coefficient, ukuze ukubalwa kwangaphakathi kwesixhobo Ukugeleza komahluko kube ngu-0.

Ukuze kuphuculwe ngakumbi uvakalelo lwesenzo kwimeko yeziphene zangaphakathi kwaye kuthintelwe ngokuthembekileyo umbane ongalinganiyo weziphene zangaphandle, ukhuselo lomahluko olude lusebenzisa into eyahlukileyo ene-curve echaza umlinganiselo wokubhuleka. I-axis ethe nkqo ye-curve yokubhuleka yomlinganiselo yi-current echaza umlinganiselo, i-axis ethe tye yi-current yokubhuleka, inxalenye ephezulu ye-curve yindawo yesenzo, kwaye inxalenye esezantsi yindawo yokubhuleka. Ii-curve ezikhoyo zahlulwe kakhulu zibe ziintlobo ezimbini: uhlobo oluqhekekileyo olunezigaba ezibini kunye nohlobo oluqhekekileyo olunezigaba ezintathu.

I-braking curve enamacandelo amabini e-broken-line ratio curve iboniswe kumfanekiso osekhohlo woMfanekiso 4. I-curve inokuba luhlobo lwe-ABC oludlula kwi-original, okanye uhlobo lwe-ABD olungadluli kwi-original. Uninzi lwezixhobo luhlobo lwe-ABC.

I-braking ratio curve enamacandelo amathathu iboniswe kumfanekiso osekunene kuMfanekiso 4, onokwahlulwahlulwa ube ziintlobo ezimbini, enye ngumgca othe tye wecandelo le-AB, kwaye enye ngumgca othe tyaba wecandelo le-AB. Izixhobo ezinomgca othe tyaba kwicandelo le-AB ziquka iGuodian Nanzi PST-1200U, i-ABB's RET-316, iXuji WBH-801 kunye ne-SEL-387, kwaye izixhobo ezinomgca othe tyaba kwicandelo le-AB ziquka iSifang CSC-326, iShenrui PRS-778 kunye neSouth Swiss RCS-978.

02

Indlela yokujonga ukhuseleko lokwahluka

Ukuqinisekiswa kokhuselo lokwahluka kobude obude kwenziwa ngokwe-ratio braking characteristic curve, ukhuseleko olungaphezulu kwe-curve luyasebenza, kwaye ukhuseleko olungaphantsi kwe-curve alusebenzi:

1) Khetha inqaku. Khetha amanqaku ama-3-5 ukuze uqinisekise ukhuselo lomahluko olude, inqaku lokuqala likhethwe kwi-axis ethe nkqo yoMfanekiso 4 ukuqinisekisa ubuncinci bomsinga osebenzayo i-Iop.min; amanqaku esibini nawesithathu akhethwe kwinqaku lokutshintsha ukuze kuqinisekiswe i-Ires yangoku yenqaku lokutshintsha; ukongeza, Khetha inqaku kwithambeka ngalinye ukuqinisekisa ithambeka.

2) Bala ixabiso. Bala ixabiso lokuqalisa, ibhalansi, kunye nebhalansi yecala ngalinye le-transformer; uze ubale ubungakanani bangoku kunye ne-engile yesigaba secala ngalinye lendawo yokujonga ngokwe-ratio braking curve yesixhobo.

3) Qinisekisa igophe. Sebenzisa indlela ye-fixed variable ukulungisa umbane omnye kwindawo yokujonga kwaye utshintshe ubungakanani bomnye umbane, ukuze uhambise indawo yokujonga phezulu nasezantsi kwindawo yesenzo nakwindawo yokuqhobosha ukuqinisekisa ukuba isixhobo sokukhusela sisebenza ngokuchanekileyo na.

03

Izixhobo ezincedisayo zokukhusela umahluko

Ukuze ukhuseleko lokwahluka luthembeke ngakumbi, ingqiqo yokhuseleko ikwabandakanya izinto ezifana nokuqala, ukuqhawuka ngokukhawuleza, kunye nokutshixa:

1) Into yokuqalisa: I-variable yokuqala ibandakanya ixabiso eliphezulu le-differential current yesigaba sesithathu, ubungakanani be-current mutation, njl. Xa i-original variable inkulu kunexabiso lokuqalisa, isixhobo sokukhusela sivula i-differential protection.

2) I-Differential quick-break element: Kwinqanaba eliphezulu le-short-circuit current, ngenxa yokugcwala kwe-current transformer, i-harmonic yesibini ivelisa i-braking torque enkulu kwaye i-differential element iyala ukuhamba. Ukuze kuthintelwe ukwala ukukhuselwa, i-differential quick-acting element ifakwa kwisixhobo. Xa i-short-circuit current ifikelela amaxesha angama-4 ~ 10 kune-rated current, i-quick-acting element ishukuma ngokukhawuleza iye kwindawo yokuphuma. Ukongeza, ukuze kuthintelwe isenzo esingalunganga sokukhuselwa ngenxa yokungangqinelani kweempawu ze-transient ze-current transformers kwicala ngalinye xa kukho i-short-circuit current enkulu, iimpawu ezifanelekileyo ze-current transformers kwicala ngalinye lokukhuselwa kokwahluka kwezixhobo eziphambili kuquka ii-transformers kufuneka zihambelane (Ii-Countermeasures ezilishumi elinesibhozo 15.1. 10). Icala le-high-voltage le-No. 2 main transformer ye-substation liqhagamshelwe kwi-string yesibini ye-2/3 wiring, kwaye le string iqhagamshelwe kwenye i-tie line; Ngowama-2017, kwenzeka impazamo yomhlaba wesigaba esinye kwisigaba B seswitshi kumtya, kunye neeseti ezimbini zokhuseleko lokwahluka komzimba wetransformer ephambili. Into ekhawulezayo isebenza ukusika iiswitshi kwicala ngalinye letransformer ephambili; ukhuselo lokwahluka lwangoku lwesigaba esiqhekekileyo kumacala omabini omgca wokuncamathela lunqumla isigaba B seswitshi esecaleni esihambelanayo, kwaye emva koko ukuphinda kusebenze kwesigaba esinye kuyaphumelela.

3) Into ebangela ukuvalwa kwe-inrush evuselelayo: Xa i-transformer ye-airdrop kunye ne-short circuit engaphandle kwendawo ye-transformer zinqunyulwe, kuya kuveliswa umsinga omkhulu ovuselelayo we-inrush. Ukuze kuthintelwe umsinga oguquguqukayo obangelwa ngumsinga ovuselelayo we-inrush ekubeni ubangele ukungasebenzi kakuhle kwesixhobo, into ebangela ukuvalwa kwe-inrush current imiselwe ukukhusela umahluko we-longitudinal, kusetyenziswa i-waveform distortion (i-waveform yangoku eguquguqukayo okanye engalinganiyo), ukuchongwa kwe-harmonic component (umxholo wesibini okanye wesithathu we-harmonic), ukuchongwa kwe-fuzzy identification ye-inrush current evuselelayo. Nangona kunjalo, xa i-transformer iphoswe emoyeni, ingakumbi kwi-airdrop yokuqala, ukhuseleko lwe-differential luya kuhlala lungasebenzi kakuhle ngenxa yokungoneli kokukhupha i-gauss yomzimba oyintloko, kwaye umxholo we-harmonic womsinga oguquguqukayo we-airdrop unokuba ngaphantsi komda wokuvala we-harmonic component. Ukuze kupheliswe ngokusisiseko impembelelo ye-residual magnetism kwi-transformer engenanto yokutshaja, singathatha amanyathelo okukhupha i-gauss kwaye senze enye i-charge engenanto, okanye sinciphise okwethutyana umda wesibini wokuvimba we-harmonic ukuqinisekisa ukusebenza okuqhelekileyo kwe-transformer ephambili.

4) Into yokuqhawula i-CT: Xa isigaba sesibini se-CT siqhawuliwe, umsinga womahluko ngumthwalo womthwalo wesigaba sokuqhawula, kwaye ukhuseleko lunokungasebenzi kakuhle. Ngeli xesha, umsinga we-zero-sequence, umsinga wesigaba uyatshintsha, ukuhla okungaqhelekanga kwe-voltage yesigaba, njl.njl. kunokusetyenziswa ukugweba ukuqhawula i-CT.

5) Isixhobo sokuthintela ukugcwala kwe-CT: Xa kuvela impazamo yangaphandle, ukugcwala kwe-CT kuya kubangela ukungasebenzi kakuhle kokhuseleko lokwahluka, ngoko ke isixhobo sokukhusela sixhotyiswe ngesixhobo sokufumanisa ukugcwala kwe-CT. Xa i-CT igcwele, umsinga wokwahluka uyenzeka emva kokuba i-CT igcwele ixesha elithile, ngoko ke isixhobo sisebenzisa ukuhambelana kwexesha komsinga wokubhuleka kunye nomsinga wokwahluka ukugweba ukuba i-CT igcwele na. Ukongeza, ukuze kuncitshiswe impembelelo yokugcwala kwe-CT kukhuseleko lokwahluka kwe-transformer longitudinal, ii-current transformers ezine-accurate limit factor (ALF) kunye ne-higher rated inflection point voltage (18 items countermeasures 15.1.12).

Icandelo 3: Intshayelelo kwezinye iindlela zokukhusela umahluko

1.

ukhuseleko lokwahluka kwecala elihlukanisiweyo

Ukhuselo lomahluko oluqhekekileyo lukhuselo lomahluko oluthatha ukujija kwe-Y-side ye-transformer njengento ekhuselweyo, kwaye lwenziwe yi-CT yokuqala neyokugqibela yee-windings kwicala ngalinye ngokwesigaba. Ukuthatha isigaba sokuzidibanisa A kuMfanekiso 5 njengomzekelo, ukhuseleko lwenziwe yi-TA1A, TA2a' kunye ne-TA3A. Ngokomthetho wangoku kaKirchhoff, akukho budlelwane bokudibanisa i-electromagnetic phakathi kwe-currents kuzo zombini iziphelo, ngoko ke ukhuseleko aludingi izinto zokuthintela i-inrush current, izinto ze-differential snap-action kunye nezinto zokuthintela i-over-excitation. Ukongeza, ixabiso elimiselweyo lombane osebenzayo wokhuseleko lomahluko oluqhekekileyo luphantsi, kwaye uvakalelo luphezulu kunolo lokhuseleko lomahluko olude. Kodwa ingxaki yolu khuseleko kukuba alunakukukhusela i-inter-turn short circuit.

2.

Ukhuseleko lokwahluka kwesigaba sokwahlulahlula

Ukhuselo lokwahluka kwesigaba lukhuselo lokwahluka oluthatha ukujija kwesigaba ngasinye se-transformer njengento ekhuselweyo, kwaye lwenziwe zii-CT kwicala ngalinye lokujija kwesigaba ngasinye. Umzekelo). Olu khuselo lunokubonakalisa zonke iimpazamo zesigaba esithile se-transformer ngaphandle kweentambo zecala ezine-voltage ephantsi, kodwa kufuneka into yokuvimba umsinga wokungena.

3.

Ukhuseleko lokwahluka kweeseli kwicala le-voltage ephantsi

Ekubeni ukhuselo lokwahlukana oluqhekeka ngesigaba lungenalo uluhlu lokhuseleko lweengcingo ze-lead kwicala le-voltage ephantsi, umahluko weseli ungeniswa njengesongezelelo kwi-differential yokwahlukana kwesigaba. Ukhuselo lokwahlukana koluntu olusecaleni lwe-voltage ephantsi lwenziwe yi-CT yangaphakathi ye-triangular two-phase winding kwicala le-voltage ephantsi kunye ne-CT ebonisa umsinga wokwahlukana we-two-phase winding. Into ethintela ukungena, kodwa ayiphenduli kwiimpazamo zokujika-ukujika.

4.

Ukhuseleko lokwahluka kolandelelwano olungenanto

Ukhuselo lomahluko we-zero-sequence luquka ii-transformers zangoku ze-zero-sequence kwicala elingathathi cala le-transformer kunye neesekethe ze-zero-sequence zee-transformers zangoku kwicala leenkwenkwezi ze-transformer. Imifanekiso 6 kunye ne-7 zii-current loops xa iimpazamo zomhlaba zenzeka ngaphandle kwendawo nangaphakathi kwendawo, ngokwahlukeneyo. Ngokufanayo, i-currents yesibini yolu khuselo ayinabo ubudlelwane be-electromagnetic coupling, ngoko ke isixhobo sokukhusela asidingi into yokuthintela i-inrush current blocking element okanye into yokuthintela i-over-excitation; kwangaxeshanye, sinovelwano ngakumbi kwi-grounding fault ye-transformer winding. Nangona kunjalo, ukhuseleko lomahluko we-zero-sequence lunokubonakalisa kuphela i-internal ground fault yecala le-voltage ephezulu nephakathi, kwaye alunakukhusela i-inter-turn short circuit.