Ukuvikelwa komehluko we-Transformer kanye neminye imikhiqizo yokuvikelwa komehluko | CANWIN

Ngaphezu kwalokho, kunezimo eziningana zokusebenza ezingajwayelekile ze-transformer, ikakhulukazi okuhlanganisa izinga eliphansi likawoyela, izinga lokushisa eliphezulu likawoyela noma ingcindezi, i-voltage ephezulu ye-transformer neutral point, ukugcwala ngokweqile, i-overcurrent, i-overexcitation, njll.

Ukuze siqaphe amaphutha ahlukene noma izimo zokusebenza ezingavamile, simise izivikelo ezahlukene, ezihlukaniswe ngokuvikelwa okuyinhloko kanye nokuvikelwa kokusekelayo, kanti isivikelo esiyinhloko sinezici zesenzo esisheshayo.

Ingxenye 2: Ukuvikelwa kokwehluka

Ukuvikelwa kokwehluka okude kungenye yezivikelo eziyinhloko ze-transformer, futhi ukuvikelwa kusebenza ngokushesha ukuze kukhubeke amaswishi ohlangothini ngalunye. Indawo yokuvikela yingxenye ephakathi kwama-transformer amanje ohlangothini ngalunye lokuvikelwa kokwehluka, kufaka phakathi umzimba we-transformer, imigqa yokuhola phakathi kwe-transformer yamanje kanye ne-transformer. Ngo-2017, i-arrester ohlangothini lwe-35kV lwe-transformer eyinhloko enguNombolo 2 yesiteshi esincane esingu-220kV yayine-flashover yesigaba se-AB, kanti i-chassis ye-arrester yaphulwa ngokukhishwa; ngoba i-arrester engu-35kV yayitholakala phakathi kwe-transformer ye-rheological kanye ne-transformer eyinhloko ohlangothini oluphansi lwe-transformer eyinhloko, yayingaphakathi kobubanzi bokuvikelwa kokwehluka okude. Amasethi amabili okuvikelwa kwe-transformer eyinhloko wonke asebenza kahle, futhi iphutha lahlukaniswa.

01

Umqondo oyisisekelo wokuvikelwa okuhlukile

Isivikelo sokwehluka kwe-transformer esikhona sisebenzisa idivayisi yokuvikela i-microcomputer, kanti ugesi wesigaba ngasinye ungena kudivayisi yokuvikela ngokulandelana, kanti isivikelo sokwehluka kwe-longitudinal siqashelwa yi-algorithm yesofthiwe. Sithatha isigaba esisodwa njengesibonelo ukuze sibonise isimiso esiyisisekelo sokuvikela ukuhluka kwe-longitudinal.

"I-felt" yamanje ehlukile yidivayisi evikelayo iyisamba se-vector se-secondary currents yama-coil amabili. Njengoba kuboniswe ku-Figure 1, lapho uhlelo lusebenza ngokujwayelekile noma lufinyelelwa ngaphandle, i-secondary currents yama-coil amabili iyafana ngobukhulu futhi iphambene ne-polarity, kanti i-differential current ingu-0, futhi isivikelo asisebenzi ngalesi sikhathi. Njengoba kuboniswe ku-Figure 2, lapho kwenzeka iphutha lomhlabathi ngaphakathi kobubanzi bokuvikela, i-secondary currents ilingana ngobukhulu kanye ne-polarity, kanti i-differential current iyisamba se-secondary currents. Lapho inani lokuqala lokuhlukanisa lifinyelelwa, isivikelo siyasebenza.

Ngokusekelwe endleleni yokuxhumanisa ikhoyili yesibili ye-rheological ngenhla, ukuvikelwa kokwehluka kwe-longitudinal kwenezela ukulungiswa kwesigaba, ukuqedwa kwamanje okulandelanayo okungu-zero, kanye nokuguqulwa kwe-amplitude kuma-vector wamanje ezinhlangothini ezahlukene ukuze kwakheke indlela yokubala yamanje okungafani, bese kwethula ijika elichaza ukubhuleka kwesilinganiso. Kwakha umqondo oyisisekelo wokuvikela.

Uma sithatha izintambo ze-YN-d11 njengesibonelo, umdwebo wezintambo kanye nomdwebo we-phasor wamanje kuboniswe kuMfanekiso 3. Kungabonakala ukuthi ngenxa yokuthi kukhona umehluko we-angle engu-30° phakathi kwama-phasor aseceleni aphezulu naphansi, isamba se-vector sama-currents amabili asiwona u-0 ngesikhathi sokusebenza okuvamile, futhi ukuguqulwa kwesigaba kuyadingeka kuqala. Ngemva kokuguqulwa, izinhlangothi eziphakeme neziphansi zesigaba esifanayo zinesigaba esifanayo.

Kunezindlela ezimbili zokuguqulwa kwesigaba, enye isekelwe ohlangothini lwe-Y, ukuze isigaba samanje se-d-side sihambisane nesigaba samanje se-Y-side, esibizwa ngokuthi "inkanyezi ye-angle", ukuvikelwa kwenkanyezi ye-angle okuvame kakhulu yi-Narui Jibao RCS-978 njll., ifomula yokuguqulwa yile:

Esinye sisekelwe ohlangothini luka-d, ukuze isigaba samanje sohlangothi luka-Y sihambisane nesohlangothi luka-d, olubizwa ngokuthi "i-angle yokujikeleza kwezinkanyezi". Iningi lamadivayisi okuvikela akhona asebenzisa indlela ye-angle yokujikeleza kwezinkanyezi, futhi ifomula yokuguqula yile:

Inhloso yokususwa kwamanje okulandelana kwe-zero ukuvimbela ukusetshenziswa kabi kokuvikelwa kokwehluka kwe-longitudinal. Ku-wiring ye-YN-d, lapho kwenzeka iphutha lomhlabathi ngaphandle kohlangothi lwe-high-voltage, ugesi olandelana kwe-zero ugeleza ohlangothini lwe-Y olune-voltage ephezulu, kodwa akukho ugesi olandelana kwe-zero ohlangothini lwe-low-voltage d, futhi ugesi olandelana kwe-zero ezinhlangothini zombili awukwazi ukulinganiswa, ngakho-ke ukuvikelwa kokwehluka kuzosebenza kabi. Kumodi yokuguqulwa kwe-"star rotation angle", umehluko phakathi kogesi omabili ngemuva kokushintsha kwesigaba ohlangothini lwe-Y uhlanze ugesi o-zero, ngakho-ke akukho zinyathelo okudingeka zithathwe. Kumodi yokuguqulwa kwe-"angle-to-star", isinxephezelo samanje se-zero-sequence senziwa ku-vector yamanje ye-Y, futhi ifomula yesinxephezelo yile:

Ngenxa yomehluko wesilinganiso sokuguqulwa kwe-transformer kanye nesilinganiso sokuguqulwa kwe-rheological sohlangothi ngalunye, i-amplitude yesibili yamanje ohlukile ohlangothini ngalunye lwe-transformer ayikwazi ukufana ngesikhathi sokusebenza okuvamile noma iphutha langaphandle. Ngalesi sikhathi, kuyadingeka ukwenza ukuguqulwa kwe-amplitude, ukuthatha inani lamanje ohlangothini olulodwa njengereferensi, ukubala i-balance coefficient kolunye uhlangothi ngokwe-voltage kuzo zombili izinhlangothi kanye ne-rheological ratio, bese uphinda-phinda i-current kolunye uhlangothi nge-balance coefficient, ukuze ukubalwa kwangaphakathi kwedivayisi Ukugeleza komehluko kube ngu-0.

Ukuze kuthuthukiswe ukuzwela kwesenzo uma kwenzeka amaphutha angaphakathi futhi kugwenywe ngokuthembekile ugesi ongalingani wamaphutha angaphandle, ukuvikelwa komehluko wesikhathi eside kusebenzisa isici somehluko esinejika elibonisa ukubhuleka kwesilinganiso. I-axis eqondile yejika elibonisa ukubhuleka kwesilinganiso ijika elibonisa ukuhlukahluka, i-axis evundlile ijika elibonisa ukubhuleka, ingxenye engenhla yejika iyindawo yesenzo, kanti ingxenye engezansi iyindawo yokubhuleka. Amajika akhona anezici ahlukaniswe kakhulu ngezinhlobo ezimbili: uhlobo lwemigqa ephukile enezigaba ezimbili kanye nohlobo lwemigqa ephukile enezigaba ezintathu.

Ijika lokubhuleka elinesilinganiso somugqa ophukile elinezigaba ezimbili liboniswe esithombeni sesobunxele seSithombe 4. Ijika lingaba uhlobo lwe-ABC oludlula endaweni yokuqala, noma uhlobo lwe-ABD olungadluli endaweni yokuqala. Amadivayisi amaningi aluhlobo lwe-ABC.

Ijika lokubhuleka elinemigqa ephukile elinezigaba ezintathu liboniswe esithombeni esifanele seSithombe 4, esingahlukaniswa sibe izinhlobo ezimbili, esinye umugqa ovundlile wesigaba se-AB, kanti esinye umugqa ovundlile wesigaba se-AB. Imishini enomugqa ovundlile esigabeni se-AB ifaka i-Guodian Nanzi PST-1200U, i-ABB's RET-316, i-Xuji WBH-801 kanye ne-SEL-387, kanti imishini enomugqa ovundlile esigabeni se-AB ifaka i-Sifang CSC-326, i-Shenrui PRS-778 kanye ne-South Swiss RCS-978.

02

Indlela yokuhlola ukuvikelwa komehluko

Ukuqinisekiswa kokuvikelwa kokwehluka kobude obude kwenziwa ngokuya ngesilinganiso sejika elibonisa ukubhuleka, ukuvikelwa okungaphezu kwejika kuyasebenza, kanti ukuvikelwa okungaphansi kwejika akusebenzi:

1) Khetha iphuzu. Khetha amaphuzu angu-3-5 ukuze kuqinisekiswe ukuvikelwa kokwehluka kwe-longitudinal, iphuzu lokuqala likhethwa ku-axis eqondile ye-Figure 4 ukuqinisekisa ubuncane bokusebenza kwamanje i-Iop.min; amaphuzu esibili nelesithathu akhethwa ku-inflection point ukuqinisekisa i-inflection point yamanje i-Ires; ngaphezu kwalokho, Khetha iphuzu ku-slope ngayinye ukuqinisekisa i-slope.

2) Bala inani. Bala inani lokuqalisa, i-balance coefficient, kanye nebhalansi yohlangothi ngalunye lwe-transformer; bese ubala ubukhulu bamanje kanye ne-phase angle yohlangothi ngalunye lwendawo yokuhlola ngokuya nge-ratio braking curve yedivayisi.

3) Qinisekisa ijika. Sebenzisa indlela yokuguquguquka okuhleliwe ukulungisa ugesi owodwa endaweni yokuhlola bese ushintsha usayizi wogesi omunye, ukuze uhambise indawo yokuhlola phezulu naphansi endaweni yesenzo kanye nendawo yokubhuleka ukuqinisekisa ukuthi idivayisi yokuvikela isebenza kahle yini.

03

Izingxenye ezisizayo zokuvikela umehluko

Ukuze kwenziwe ukuvikelwa kokwehluka kuthembeke kakhudlwana, umqondo wokuvikela uhlanganisa nezinto ezifana nokuqala, ukuphuka okusheshayo, kanye nokukhiya:

1) Isici sokuqala: I-variable yokuqala ifaka inani eliphezulu lamanje ohlukile wesigaba sesithathu, inani lokuguqulwa kwamanje, njll. Uma i-variable yokuqala inkulu kunanoma yiliphi inani lokuqala, idivayisi yokuvikela ivula i-differential protection.

2) Isici sokuphuka okusheshayo okuhlukile: Ezingeni eliphezulu lamandla kagesi omfushane, ngenxa yokugcwala kwe-transformer yamanje, i-harmonic yesibili ikhiqiza i-torque enkulu yokubhuleka futhi isici sokuhluka senqaba ukuhamba. Ukuze kugwenywe ukwenqatshwa kokuvikelwa, kufakwa isici sokusebenza okusheshayo okuhlukile kudivayisi. Lapho amandla kagesi omfushane efika izikhathi ezingu-4 ~ 10 zamandla kagesi alinganiselwe, isici sokusebenza okusheshayo sithuthela ngokushesha endaweni yokukhipha. Ngaphezu kwalokho, ukuze kuvinjelwe isenzo esingalungile sokuvikelwa ngenxa yokungahambisani kwezici zesikhashana zama-transformer amanje ohlangothini ngalunye lapho kukhona amandla kagesi omfushane amakhulu, izici ezifanele zama-transformer amanje ohlangothini ngalunye lokuvikelwa okuhlukile kwemishini eyinhloko kufaka phakathi ama-transformer kufanele zihambisane (Izilinganiso Eziyishumi Nesishiyagalombili 15.1. 10). Uhlangothi oluphezulu lwamandla kagesi lwe-transformer eyinhloko enguNombolo 2 yesiteshi esincane luxhunywe kuntambo yesibili yocingo lwe-2/3, futhi le ntambo ixhunywe komunye umugqa wokubopha; Ngo-2017, kwenzeka iphutha lomhlabathi lesigaba esisodwa esigabeni B seswishi entanjeni, kanye namasethi amabili okuvikela okuhlukile komzimba we-transformer eyinhloko. Isici esisheshayo sisebenza ukunquma amaswishi ohlangothini ngalunye lwe-transformer eyinhloko; ukuvikelwa kokuhlukana kwamanje kwesigaba esihlukanisiwe ezinhlangothini zombili zomugqa wokubopha kunquma isigaba B seswishi eseceleni ehambisanayo, bese ukubuyiselwa kwesigaba esisodwa kuphumelele.

3) Isici esivusa amadlingozi sokuvimba i-inrush: Lapho i-transformer ye-airdrop kanye ne-short circuit engaphandle kwendawo ye-transformer kunqanyulwa, kuzokhiqizwa ugesi omkhulu ovusa amadlingozi. Ukuze kuvinjelwe ugesi ohlukile obangelwa ugesi ovuselela amadlingozi ukuthi ungabangela ukuthi idivayisi ingasebenzi kahle, kulungiselelwa ugesi ovimbela amadlingozi wokuvikela umehluko wesikhathi eside, kusetshenziswa ukuphambuka kwesimo samagagasi (i-waveform yamanje ehlukanisayo engavamile noma engalingani), ukuhlonza ingxenye ye-harmonic (okuqukethwe kwesibili noma kwesithathu kwe-harmonic), ukuhlonza ukuhlonza okufiphele kogesi we-inrush ovusa amadlingozi. Kodwa-ke, lapho i-transformer idonswa emoyeni, ikakhulukazi kugesi wokuqala, ukuvikelwa komehluko kuzoqhubeka nokungasebenzi kahle ngenxa yokukhipha igesi okunganele emzimbeni oyinhloko, futhi okuqukethwe kwe-harmonic kogesi ohlukanisa amadlingozi womoya kungase kube ngaphansi kunomkhawulo wokuvimba ingxenye ye-harmonic. Ukuze siqede ngokuphelele ithonya le-magnetism eseleyo ekushajweni okungenalutho kwe-transformer, singathatha izinyathelo zokususa igesi futhi senze okunye ukushaja okungenalutho, noma sehlise okwesikhashana umkhawulo wesibili wokuvimba i-harmonic ukuqinisekisa ukusebenza okuvamile kwe-transformer eyinhloko.

4) Isici sokunqamula i-CT: Uma isigaba sesibili se-CT sinqamukile, ugesi ohlukile ungugesi womthwalo wesigaba sokunqamula, futhi ukuvikelwa kungase kungasebenzi kahle. Ngalesi sikhathi, ugesi wokulandelana okungu-zero, ugesi wesigaba uyashintsha, ugesi wesigaba ukwehla ngokuzumayo kwe-voltage yesigaba, njll. kungasetshenziswa ukwahlulela ugesi wokukhipha i-CT.

5) Isici sokuvimbela ukugcwala kwe-CT: Uma kwenzeka iphutha langaphandle, ukugcwala kwe-CT kuzobangela ukungasebenzi kahle kokuvikelwa kokwehluka, ngakho-ke idivayisi yokuvikela ifakwe isici sokuthola ukugcwala kwe-CT. Uma i-CT igcwele, ukugcwala kokwehluka kwenzeka ngemva kokuba i-CT igcwele isikhathi esithile, ngakho idivayisi isebenzisa ukuhambisana kwesikhathi kokubhuleka kanye nokugcwala kokwehluka ukuze yahlulele ukuthi i-CT igcwele yini. Ngaphezu kwalokho, ukuze kuncishiswe umthelela wokugcwala kwe-CT ekuvikelweni kokwehluka kwe-transformer longitudinal, ama-transformer amanje ane-accurate limit factor (ALF) kanye ne-higher rated inflection point voltage (izinto ezingu-18 countermeasures 15.1.12).

Ingxenye 3: Isingeniso kwezinye izivikelo zokwehlukanisa

1.

ukuvikelwa kokwehluka kwecala elihlukanisiwe

Ukuvikelwa kokwehluka kwezinhlangothi ezihlukanisiwe kuyisivikelo sokwehluka esithatha ukugoba kwe-Y-side kwe-transformer njengento evikelwe, futhi sakhiwe yi-CT yokuqala neyokugcina yama-winding ohlangothini ngalunye ngokwesigaba. Uma sithatha isigaba sokuzihlanganisa A kuMfanekiso 5 njengesibonelo, isivikelo sakhiwe yi-TA1A, TA2a' kanye ne-TA3A. Ngokomthetho wamanje kaKirchhoff, abukho ubudlelwano bokuxhumanisa be-electromagnetic phakathi kwama-current kuzo zombili izinhlangothi, ngakho-ke isivikelo asidingi izinto zokuvimba zamanje ezi-inrush, izinto ze-differential snap-action kanye nezinto zokuvimba ezi-over-excitation. Ngaphezu kwalokho, inani eliqinile lamanje osebenzayo lesivikelo sokwehluka kwezinhlangothi ezihlukanisiwe liphansi, futhi ukuzwela kuphakeme kunokuvikelwa kokwehluka kwe-longitudinal. Kodwa ububi balokhu kuvikelwa ukuthi akukwazi ukuvikela i-inter-turn short circuit.

2.

Ukuvikelwa kokwehluka kwesigaba esihlukanisiwe

Ukuvikelwa kokwehluka kwesigaba kuyisivikelo sokwehluka esithatha ukugoqa kwesigaba ngasinye se-transformer njengento evikelwe, futhi sakhiwe ngama-CT ohlangothini ngalunye lokugoqa kwesigaba ngasinye. isibonelo). Lokhu kuvikelwa kungabonisa wonke amaphutha esigaba esithile se-transformer ngaphandle kwama-lead ohlangothini olune-voltage ephansi, kodwa kudingeka isici sokuvimba ugesi wamanje.

3.

Ukuvikelwa kokwehluka kweseli ohlangothini lwe-voltage ephansi

Njengoba isivikelo sokwehluka kwesigaba singenalo ibanga lokuvikela izintambo zomthofu ohlangothini olune-voltage ephansi, ukwehluka kweseli kwethulwa njengesengezo sokwehluka kwesigaba. Ukuvikelwa kokwehluka komphakathi ohlangothini olune-voltage ephansi kwakhiwe yi-CT yangaphakathi yokujikeleza kwesigaba ezimbili okunxantathu ohlangothini olune-voltage ephansi kanye ne-CT ekhombisa ukugeleza kokwehluka kokujikeleza kwesigaba ezimbili. Into evimba ukungena, kodwa ayiphenduli emaphutheni okujika nokujika.

4.

Ukuvikelwa kokwehluka kwe-Zero sequence

Ukuvikelwa kokwehluka kwe-zero-sequence kuqukethe ama-transformer wamanje we-zero-sequence ohlangothini lwephuzu elingathathi hlangothi le-transformer kanye nama-circuits e-zero-sequence ama-transformer wamanje ohlangothini lwenkanyezi ye-transformer. Izibalo 6 no-7 ziyizihibe zamanje lapho amaphutha omhlaba evele ngaphandle kwendawo nangaphakathi kwendawo, ngokulandelana. Ngokufanayo, ama-current esibili alokhu kuvikelwa awanayo i-electromagnetic coupling relationship, ngakho-ke idivayisi yokuvikela ayidingi i-excitation inrush current blocking element noma i-over-excitation blocking element; ngesikhathi esifanayo, ibucayi kakhulu ephutheni lomhlabathi le-transformer winding. Kodwa-ke, ukuvikelwa kokwehluka kwe-zero-sequence kungabonisa kuphela iphutha langaphakathi lomhlabathi ohlangothini lwe-voltage ephezulu nephakathi, futhi akukwazi ukuvikela i-inter-turn short circuit.