Ukuhlaziywa Kokuvikelwa Kwe-Transformer Ekuvikelweni Kwe-Relay

1. Amaphutha avamile kanye nokukhubazeka kwama-transformer

Amaphutha e-transformer angahlukaniswa ngamaphutha angaphakathi kanye namaphutha angaphandle.

Amaphutha angaphakathi abhekisela kumaphutha ayenzeka ngaphakathi kwekesi, okuhlanganisa amaphutha okujikeleza kwesigaba kuya kwesigaba, amaphutha okujikeleza kwesigaba esisodwa phakathi kokujika, amaphutha okujikeleza kwesigaba esisodwa phakathi kokujika kanye nezinsimbi, kanye namaphutha okunqamula ama-winding.

Amaphutha angaphandle abhekisela kumaphutha ahlukahlukene okujikeleza okufushane kwesigaba kuya kwesigaba phakathi kwezintambo zomthofu zangaphandle ze-transformer, kanye namaphutha omhlaba wesigaba esisodwa ayenzeka lapho i-insulating bushing yezintambo zomthofu ikhanya ngegobolondo lebhokisi.

Ukwehluleka kwe-transformer kuyingozi kakhulu. Ikakhulukazi uma kwenzeka iphutha langaphakathi, i-arc yokushisa ephezulu ekhiqizwa ugesi we-short-circuit ngeke nje ishise i-insulation kanye ne-iron core ye-transformer winding, kodwa futhi ibangele ukuthi uwoyela we-transformer ubole futhi ukhiqize inani elikhulu legesi, okubangela ukuguqulwa noma ngisho nokuqhuma kwegobolondo le-transformer. Ngakho-ke, kumele inqunywe lapho i-transformer yehluleka.

Izimo ezingavamile ze-transformer zifaka phakathi ukugcwala ngokweqile, izinga eliphansi likawoyela, ugesi ongaphezulu obangelwa yi-external short circuit, izinga lokushisa eliphezulu likawoyela le-transformer esebenza, izinga lokushisa eliphezulu lokugoba, umfutho ophezulu we-transformer, kanye nokwehluleka kohlelo lokupholisa. Uma i-transformer isesimweni sokusebenza esingajwayelekile, kufanele kunikezwe isignali ye-alamu.

2. Ukucushwa kokuvikelwa kwe-transformer

Isivikelo esiyinhloko samaphutha e-short-circuit: ikakhulukazi isivikelo sokwehluka kwe-longitudinal, isivikelo segesi esindayo, njll.

Ukuvikelwa kwesipele kwamaphutha e-short-circuit: ikakhulukazi ukuvikelwa kokuvimbela i-voltage ehlanganisiwe ngokweqile, ukuvikelwa kokulandelana kwe-zero (isiqondiso) ngokweqile, ukuvikelwa kokuvimbela okuphansi, njll.

Ukuvikelwa kokusebenza okungajwayelekile: ikakhulukazi kufaka phakathi ukuvikelwa kokulayisha ngokweqile, ukuvikelwa kokuvusa ngokweqile, ukuvikelwa kwegesi elula, ukuvikelwa kwegebe lamaphuzu angathathi hlangothi, izinga likawoyela lokushisa kanye nokuvikelwa kokuhluleka kohlelo lokupholisa, njll.

3. Ukuvikelwa okungekona ugesi

Ukuvikelwa kwe-transformer kusetshenziswa ubuningi obungebona ugesi njengowoyela, igesi, kanye nokushisa kwe-transformer kubizwa ngokuthi ukuvikelwa okungebona ugesi. Ngokuyinhloko kuhlanganisa ukuvikelwa kwegesi, ukuvikelwa kwengcindezi, ukuvikelwa kokushisa, ukuvikelwa kwezinga likawoyela kanye nokuvikelwa kokuma okupholile. Ukuvikelwa okungebona ugesi kusebenza ekukhubekeni noma ekuthumeleni incwadi ngokwezidingo zesayithi.

(1) Ukuvikelwa kwegesi

Uma kwenzeka iphutha ngaphakathi kwe-transformer, ngenxa yesenzo samandla kagesi afushane kanye ne-arc endaweni ye-short-circuit, kuzokhiqizwa inani elikhulu legesi ngaphakathi kwe-transformer, futhi ijubane lokugeleza kukawoyela le-transformer lizosheshiswa. Ukuvikelwa okutholakala ngokusebenzisa ukugeleza kwegesi namafutha kubizwa ngokuthi ukuvikelwa kwegesi.

Ukuvikelwa kwegesi elincane: Uma kwenzeka iphutha elincane noma ukungahambi kahle ngaphakathi kwe-transformer, iphuzu lephutha liyashiswa ngokweqile, okwenza ingxenye kawoyela ikhule, igesi etholakala ku-oyili yakha amabhamuza bese ingena ku-relay yegesi, futhi ukuvikelwa kwegesi elikhanyayo kusebenza ukuthumela isignali yegesi elikhanyayo.

Ukuvikelwa kwegesi esindayo: Uma kwenzeka iphutha elikhulu ethangini likawoyela we-transformer, ugesi wephutha uba mkhulu, futhi i-arc ibangela ukuthi inani elikhulu likawoyela we-transformer libole, okubangela inani elikhulu legesi kanye nokugeleza kukawoyela. Ukuphazamiseka komthelela kwenza isivikelo sokudluliselwa kwegesi esindayo sisebenze, sithumele isignali yegesi esindayo bese siphazamisa ukuphuma. Susa i-transformer.

Ukuvikelwa kwegesi esindayo kuyisivikelo esiyinhloko samaphutha angaphakathi ethangi likawoyela, futhi kungabonakalisa amaphutha ahlukahlukene ngaphakathi kwe-transformer. Uma inani elincane lamasekethe amafushane aphakathi kokujika livela ku-transformer, yize ugesi wephutha mkhulu, ugesi we-differential okhiqizwa ekuvikelweni komehluko ungase ungabi mkhulu, futhi ukuvikelwa komehluko kungase kwenqabe ukusebenza. Ngakho-ke, ngephutha langaphakathi le-transformer, kuyadingeka ukuthembela ekuvikelweni kwegesi esindayo ukuze kususwe iphutha.

(2) Ukuvikelwa kwengcindezi

Ukuvikelwa kwengcindezi nakho kuyisivikelo esiyinhloko emaphutheni angaphakathi ethangini le-transformer. Kuqukethe ukukhululeka kwengcindezi kanye nokuvikelwa kokushintsha kwengcindezi ngokuzumayo, okusetshenziselwa ukuphendula ekucindezelweni kukawoyela we-transformer.

(3) Ukuvikelwa kwezinga lokushisa kanye namafutha

Uma izinga lokushisa le-transformer lenyuka lifinyelela enanini lesixwayiso, isivikelo sokushisa sizothumela isignali ye-alamu, bese siqala i-standby cooler.

Uma uwoyela we-transformer uvuza noma izinga likawoyela lehla ngenxa yezinye izizathu, ukuvikelwa kwezinga likawoyela kuzosebenza futhi kuthumele isignali ye-alamu.

(4) Ukuvikelwa kokuma okupholile

Uma i-transformer cooler esebenza imisiwe ngokuphelele, izinga lokushisa le-transformer lizokhuphuka. Uma ingaphathwa ngesikhathi, ingabangela umonakalo ekushiseni kwe-transformer winding. Ngakho-ke, lapho i-cooler imisiwe ngokuphelele ngesikhathi sokusebenza kwe-transformer, isivikelo sizothumela isignali ye-alamu bese sinqamula i-transformer ngemva kokulibala isikhathi eside.

4. Ukuvikelwa okuhlukile

Ukuvikelwa komehluko we-transformer kuyisivikelo esiyinhloko senani likagesi le-transformer, futhi ububanzi bayo bokuvikelwa buyingxenye ezungezwe ama-transformer amanje ohlangothini ngalunye. Uma kwenzeka amaphutha afana ne-phase-to-phase short-circuit kanye ne-inter-turn short-circuit yokujikeleza ngaphakathi kwalolu bubanzi, ukuvikelwa komehluko kumele kusebenze.

Ngokuphathelene nesimiso sokuvikelwa komehluko we-transformer, esixoxe ngakho ngokuningiliziwe ngaphambili, abangani abakudingayo bangabuyekeza okuqukethwe okufanele kumarekhodi omlando 6, 7, kanye no-8. Ngeke ngingene emininingwaneni ngalokhu, futhi lapha ngizomane ngengeze eminye imibono mayelana nomsinga wokungenisa umoya.

(1) Ugesi ophumayo we-transformer ovuselelayo

Ugesi wokuvuselela okhiqizwa lapho i-transformer ikhishwa emoyeni ubizwa ngokuthi ugesi wokuvuselela okhishwa emoyeni. Ubukhulu bogesi wokuvuselela okhishwa emoyeni buhlobene nesakhiwo se-transformer, i-engeli yokuvala, umthamo, i-magnetism eseleyo ngaphambi kokuvala nezinye izici. Ukulinganisa kukhombisa ukuthi lapho i-transformer ikhishwa emoyeni, ugesi wokuvuselela okhishwa emoyeni ngenxa yokugcwala kwe-iron core mkhulu kakhulu, ngokuvamile izikhathi ezimbili kuya kweziyisithupha zamandla alinganiselwe, futhi umkhawulo ungaba ngaphezu kwezikhathi ezingu-8. Njengoba ugesi wokuvuselela okhishwa emoyeni ugeleza kuphela ku-transformer ohlangothini lokushaja, ugesi omkhulu wokuhlukanisa uzokhiqizwa kusekethe yokuhlukanisa, okuholela ekungasebenzi kahle kokuvikelwa kokuhlukanisa.

Umsinga wokungenisa umoya unezici ezilandelayo: a. Inani lomsinga wokungenisa umoya likhulu kakhulu futhi liqukethe izingxenye ezisobala ezingezona ezezikhathi ezithile; b. I-waveform iqondile futhi ingama-interval; c. Iqukethe izingxenye ezisobala ze-harmonic ezisezingeni eliphezulu, ikakhulukazi ingxenye yesibili ye-harmonic. Ngokusobala; d, umsinga wokungenisa umoya uyancipha.

Ngokwezici ezingenhla zamandla okungena, ukuze kuvinjelwe ukusebenza kabi kokuvikelwa kokwehluka kwe-transformer okubangelwa amandla okungena, kusetshenziswa izimiso ezintathu kule phrojekthi: okuqukethwe okuphezulu kwesibili okuvumelanayo, i-waveform engalingani, kanye ne-angle enkulu yokungaqhubeki kwe-waveform ukuze kubonakale ukuvinjelwa kokuvikelwa kokwehluka.

(2) Isimiso sesibili sokubhuleka esivumelanayo

Ingqikithi yokubhuleka kwe-harmonic yesibili ukusebenzisa ingxenye yesibili ye-harmonic ku-differential current ukuze kuhlulelwe ukuthi i-differential current iyi-fault current noma i-inrush current ethokozisayo. Uma iphesenti le-harmonic component yesibili kanye ne-fundamental wave component inkulu kunenani elithile (ngokuvamile i-20%), kugwetshwa ukuthi i-differential current ibangelwa yi-excitation inrush current, futhi ukuvikelwa kwe-differential kuvinjiwe.

Ngakho-ke, uma isilinganiso sesibili sokubhuleka kwe-harmonic sikhulu, kulapho kuvunyelwa khona ugesi wesibili we-harmonic oqukethwe kugagasi eliyisisekelo, futhi umphumela wokubhuleka uzoba mubi kakhulu.

(3) Ukuvikelwa kokuphuka okusheshayo okuhlukile

Uma kwenzeka iphutha elikhulu ngaphakathi kwe-transformer futhi i-CT igcwele ngenxa yogesi omkhulu wephutha, ugesi wesibili we-CT nawo uqukethe inani elikhulu lezingxenye ze-harmonic. Ngokusho kwencazelo engenhla, lokhu kungenzeka kubangele ukuvikelwa komehluko ngenxa yokubopha kwesibili kwe-harmonic. Vimba noma libazise isenzo. Lokhu kuzolimaza kakhulu i-transformer. Ukuze kuxazululwe le nkinga, ukuvikelwa kokuphazamiseka okusheshayo komehluko kuvame ukusethwa.

Isici sokuqhekeka okusheshayo okuhlukile empeleni siyisici sokuqhekeka esinenani eliphezulu sokuvikela ukuhlukaniswa okude. Ngokungafani nezinto ezijwayelekile zokuhlukaniswa, sibonisa inani elisebenzayo lamanje okungafani. Kungakhathaliseki ukuthi i-waveform yamanje okungafani kanye nobukhulu bengxenye ye-harmonic, uma nje inani elisebenzayo lamanje okungafani lidlula inani lokusetha lokuqhekeka okusheshayo okuhlukile (ngokuvamile liphakeme kunenani lokusetha lokuvikela ukuhlukaniswa), sizosebenza ngokushesha ukusika i-transformer ngaphandle kokukhathazeka. Ukuvinjelwa kwezindlela ezifana namanje okungena.

Okulandelayo kwethula ukuvikelwa kokusekelayo kwe-transformer

Kunezinhlobo eziningi zokulungiswa kokuvikelwa kwesipele kwama-transformer. Le nkinga iveza kakhulu izinhlobo ezimbili zokuvikelwa kwesipele: ukuvikelwa kokuvimbela i-voltage okuyinkimbinkimbi kanye nokuvikelwa kokumisa phansi kwama-transformer.

1. Ukuvikelwa kokushisa ngokweqile kokukhiya ingcindezi okuyinkimbinkimbi

Ukuvikelwa kokusebenzisa amandla kagesi aqinile okuvimba amandla kagesi angaphezu kwamandla kagesi kuyisiqinisekiso sokusekela amaphutha amakhulu naphakathi e-transformer afushane esigaba kuya kwesigaba. Kufanelekela ama-transformer akhuphukayo, ama-transformer okuxhumana nohlelo kanye nama-transformer akhuphukayo ukuvikelwa kwawo okuphezulu kwamandla kagesi okungenakuhlangabezana nezidingo zokuzwela. I-voltage ehlanganisiwe eyakhiwe yi-voltage yokulandelana okungalungile kanye ne-voltage ephansi ingabonisa amaphutha ahlukahlukene ngaphakathi kobubanzi bokuvikela, okunciphisa inani lokusetha lokuvikelwa kwamandla kagesi angaphezu kwamandla kagesi futhi kuthuthukise ukuzwela.

Ukuvikelwa kokushisa okuphezulu kwamandla kagesi ahlanganisiwe kwakhiwe yi-composite voltage element, i-overcurrent element kanye ne-time element. I-input current yokuvikela i-secondary-phase current ye-CT ohlangothini lwe-transformer, kanti i-input voltage i-secondary-phase three-phase voltage ye-PT ohlangothini lwe-transformer noma kwezinye izinhlangothi. Ukuze kuvikelwe i-microcomputer, i-voltage yalolu hlangothi inganikezwa kwezinye izinhlangothi ngesofthiwe, ukuze kuqinisekiswe ukuthi ukuvikelwa kokushisa okuphezulu kwanoma yiluphi uhlangothi kusengasetshenziswa lapho i-PT kunoma yiluphi uhlangothi ilungiswa kabusha. I-action logic iboniswe esithombeni esingezansi.

2. Ukuvikelwa kokumisa phansi kwe-transformer

Ukuvikelwa kokusekelayo kwamaphutha okujikeleza okufushane kwesisekelo sama-transformer amakhulu naphakathi ngokuvamile kufaka phakathi: ukuvikelwa kokudlula komugqa we-zero-sequence, ukuvikelwa kokudlula komugqa we-zero-sequence, ukuvikelwa kwegebe, njll. Okulandelayo isingeniso esifushane esisekelwe ezindleleni ezintathu ezahlukene zokubeka phansi zephuzu elingathathi hlangothi.

(1) Iphuzu elingathathi hlangothi lisekelwe ngqo

Kuma-transformer ane-voltage engu-110kV nangaphezulu lapho iphuzu lawo elingathathi hlangothi lisekelwe ngqo, ukuvikelwa kwamanje okulandelana okungu-zero okuphendula emaphutheni omhlaba kufanele kufakwe ohlangothini lwesistimu yokumisa yamandla amakhulu. Kuma-transformer asekelwe ngqo ezinhlangothini zombili eziphakeme neziphakathi, ukuvikelwa kwamanje okulandelana okungu-zero kufanele kube nesiqondiso, futhi isiqondiso kufanele sibhekisele emabhakeni ebhasi ohlangothini ngalunye.

Isimiso sokuvikelwa kwamanje okulandelana kwezinga-zero sifana nesokuvikelwa komugqa olandelana kwezinga-zero, sicela ubheke udaba 30. Umugqa olandelana kwezinga-zero ungathathwa kusuka kumugqa wesibili we-CT yephuzu elingathathi hlangothi, noma ungadalwa ngokwawo ngumugqa wesibili wesigaba sesithathu se-CT ohlangothini lwendawo. Umugqa olandelana kwezinga-zero oxhunywe kwisici esiqondisayo ungathathwa ku-voltage evulekile kanxantathu we-PT ohlangothini lwendawo, noma ungadalwa ngokwawo yi-voltage yesibili yesigaba sesithathu ohlangothini lwendawo. Kudivayisi yokuvikela i-microcomputer, indlela ezikhiqiza yona iyasetshenziswa kakhulu.

Kuma-transformer amakhulu anama-twing amathathu, kungasetshenziswa ukuvikelwa kwamanje kwe-zero-sequence yesigaba sesithathu. Phakathi kwawo, iSigaba I kanye neSigaba II zineziqondiso, kanti iSigaba III asinazo iziqondiso. Ngokuvamile kunamazinga amabili okulibaziseka esigabeni ngasinye, futhi ububanzi bephutha buncishiswa ngokubambezeleka okufushane (ukugxuma i-bus coupler noma i-switch ohlangothini oluyinhloko lwebha), futhi i-transformer inqanyulwa ngokubambezeleka okude (ukugxuma i-switch yezinhlangothi ezintathu). Ukucushwa kokuvikelwa okuqondile kunqunywa ngokwesimo sangempela.

Njengoba kuboniswe esithombeni, ngemva kokusebenza kwesigaba I noma II sokuvikelwa kwamanje okuqondisayo okungu-zero-sequence, qala ngokugxuma i-bus coupler noma iswishi kulolu hlangothi ngemva kokulibaziseka okufushane t1 noma t3 ukuze unciphise ububanzi bephutha. Uma iphutha lisekhona, ngemva kwesikhathi eside, gxuma i-Libazisa t2 noma t4 iswishi enezinhlangothi ezintathu ukuze unqume i-transformer. Isigaba III asinasiqondiso, futhi i-transformer iyanqunywa ngqo ngemva kokulibaziseka.

(2) Iphuzu elingathathi hlangothi alisekelwe

Ugesi we-zero-sequence udlula endaweni engathathi hlangothi ye-transformer ukuze wakhe isekethe ye-zero-sequence. Kodwa-ke, uma amaphuzu angathathi hlangothi awo wonke ama-transformer egxilile, ugesi we-short-circuit endaweni yokumisa uzoxhunywa ku-transformer ngayinye, okuzonciphisa ukuzwela kokuvikelwa kogesi we-zero-sequence overcurrent. Ngakho-ke, ukuze kukhawulelwe ugesi we-zero-sequence ngaphakathi kobubanzi obuthile, kunemithethonqubo ngenani lama-transformer asebenza nephuzu elingathathi hlangothi eligxilile.

Kuma-transformer asebenza ngaphandle kokumisa isisekelo, kufanele kulungiselelwe ukuvikelwa kwe-voltage ye-zero-sequence ukuze kuvinjelwe umonakalo we-overvoltage ku-transformer obangelwa ama-gap arc ezindaweni zamaphutha ngesikhathi samaphutha omhlaba.

Ngenxa yezinga eliphezulu lokufakwa komoya endaweni engathathi hlangothi ye-transformer efakwe ugesi ngokugcwele, lapho kwenzeka iphutha lomhlabathi ohlelweni, ukuvikelwa kwamanje kwe-zero-sequence kuzoqala kunqume i-transformer lapho iphuzu elingathathi hlangothi lisekelwe, futhi uma iphutha lisakhona, kuzoba nokuvikelwa kwe-zero-sequence voltage ukuze kunqunywe iphuzu elingathathi hlangothi ngaphandle kokufaka i-transformer endaweni ethintekile.

(3) Iphuzu elingathathi hlangothi lisekelwe ngegebe lokukhipha

Ama-transformer e-voltage ephezulu kakhulu angama-transformer angenawo ugesi, futhi ugesi we-neutral point coil phansi ubuthakathaka kunowezinye izingxenye. Ugesi we-neutral point uvame ukuphuka. Ngakho-ke, ukuvikelwa kwegebe kudinga ukulungiswa.

Umsebenzi wokuvikela igebe ukuvikela ukuphepha kokufakwa kokushisa kwephuzu elingathathi hlangothi le-transformer engaphansi komhlaba enephuzu elingathathi hlangothi.

Faka igebe lokuqhekeka phakathi kwephuzu elingathathi hlangothi le-transformer nomhlabathi njengoba kuboniswe esithombeni. Lapho iswishi yokuhlukanisa umhlabathi ivaliwe, i-transformer ifakwa emhlabathini ngqo bese kusetshenziswa isivikelo sokulandelana kwe-zero-sequence overcurrent. Lapho iswishi yokuhlukanisa umhlabathi inqanyuliwe, i-transformer ifakwa emhlabathini ngegebe bese ifakwa ekuvikelweni kwegebe.

Ukuvikelwa kwegebe kutholakala ngokusebenzisa igebe lamanje elingu-3I0 eligeleza endaweni engathathi hlangothi ye-transformer kanye ne-voltage kanxantathu wokuvula webhasi engu-3U0 njengezindinganiso.

Uma iphuzu elingathathi hlangothi liphakanyiswa ngenxa yephutha, igebe liyaphuka bese kukhiqizwa ugesi omkhulu wegebe ongu-3I0. Ngalesi sikhathi, ukuvikelwa kwegebe kuyasebenza futhi i-transformer iyanqunywa ngemva kokulibaziseka. Ngaphezu kwalokho, lapho kwenzeka iphutha lokumisa isisekelo ohlelweni, ukuvikelwa kwe-zero-sequence kwe-transformer yokumisa isisekelo ye-neutral point kusebenza, futhi i-transformer yokumisa isisekelo ye-neutral point iyanqunywa kuqala. Ngemva kokuba uhlelo lulahlekelwe iphuzu lokumisa isisekelo, uma iphutha lisakhona, i-voltage evulekile engu-3U0 yebhasi i-PT izoba nkulu kakhulu, futhi ukuvikelwa kwegebe kuzosebenza ngalesi sikhathi.