Indlela Yokukhusela Iitransformer. Indlela eyiyo yokukhusela iitransformer ingahlala ixesha elide.

I-transformer sisixhobo esingashukumiyo esisebenza rhoqo, sisebenza ngokuthembekileyo ngakumbi, amathuba amancinci okusilela. Kodwa ngenxa yokuba uninzi lwee-transformer zifakelwe ngaphandle, kwaye zichaphazeleka ngumthwalo ngexesha lokusebenza kunye nempembelelo yesiphako sesekethe esifutshane senkqubo yamandla, iimpazamo ezahlukeneyo kunye neemeko ezingaqhelekanga azinakuphepheka kwinkqubo yokusebenza.

1. Iimpazamo eziqhelekileyo kunye nokungahambi kakuhle kwee-transformers

Iziphene zetransformer zinokwahlulwa zibe ziziphene zangaphakathi neziphene zangaphandle.

Iziphene zangaphakathi zibhekisa kwiziphene ezenzeka ngaphakathi kwekhava, ezifana neziphene ze-inter-phase short-circuit of windings, iziphene ze-inter-turn short-circuit of one-phase windings, iziphene ze-short-circuit phakathi kwe-windings kunye ne-iron core, kunye neziphene zokuqhawula i-windings, njl.

Iziphene zangaphandle zibhekisa kwiiphene ezahlukeneyo zesiphatho esifutshane phakathi kwemigca yangaphandle yeetransformer kunye neziphene zokumisa umhlaba zesigaba esinye ezenzeka xa i-insulation bush yelayini yelead idlula kwikhava.

Ukusilela kwetransformer kwenza umonakalo omkhulu. Ingakumbi xa kukho impazamo yangaphakathi, i-arc yobushushu obuphezulu eveliswa ngumsinga we-short-circuit ayizukutshisa kuphela i-insulation kunye ne-iron core ye-transformer winding, kodwa ikwabangela ukuba ioyile yetransformer ibole kwaye ivelise igesi eninzi, nto leyo ekhokelela ekuguqukeni kwegobolondo letransformer kunye nokuqhuma. Ke ngoko, xa itransformer ingaphumeleli, kufuneka isuswe.

Izinto ezingaqhelekanga kwi-transformer zibangelwa kukugqithiswa kakhulu, ukuncipha kwenqanaba leoyile, i-external short circuit ebangelwa yi-overcurrent, ubushushu be-transformer osebenzayo buphezulu kakhulu, ubushushu bokujika buphezulu kakhulu, uxinzelelo lwe-transformer luphezulu kakhulu, kunye nokungasebenzi kakuhle kwenkqubo yokupholisa. Xa i-transformer ingaqhelekanga, kufuneka kunikwe isignali yesilumkiso.

Ezimbini, uqwalaselo lokhuseleko lwe-transformer

Ukhuseleko oluphambili lwempazamo yesekethe emfutshane: ukhuseleko lokwahluka olude, ukhuseleko lwegesi enzima, njl.

Ukhuseleko olukhuselekileyo lwesiphako sesekethe esifutshane: ikakhulu ukhuseleko olugqithisileyo lwe-voltage evaliweyo, ukhuseleko olungaphezulu kolandelelwano (ulwalathiso) lwe-zero, ukhuseleko oluphantsi lwe-impedance, njl.

Ukhuseleko olungaqhelekanga lokusebenza: ikakhulu ukhuseleko lomthwalo ogqithisileyo, ukhuseleko lokuvuthela kakhulu, ukhuseleko lwegesi ekhanyayo, ukhuseleko lwesithuba esingathathi cala, inqanaba leoyile yobushushu kunye nokhuseleko lokungaphumeleli kwenkqubo yokupholisa.

Ezintathu, ukhuseleko olungelulo olombane

Ukhuseleko lwe-transformer oluqulunqwe yioyile, igesi, ubushushu kunye nomthamo ongengowombane lubizwa ngokuba lukhuseleko olungengowombane. Kukho ikakhulu ukhuseleko lwegesi, ukhuseleko loxinzelelo, ukhuseleko lobushushu, ukhuseleko lwenqanaba leoyile kunye nokhuseleko lokuma okupholileyo. Ukhuseleko olungengowombane lusebenza njengoko kufuneka kwindawo ukuze kukhubeke okanye kuthunyelwe imiqondiso.

1. Ukhuseleko lwegesi

Xa i-transformer yangaphakathi ingasebenzi kakuhle, ngenxa yendima ye-current-circuit current kunye ne-short-circuit point arc, i-transformer yangaphakathi iya kuvelisa igesi eninzi, kwangaxeshanye isantya sokuhamba kweoyile ye-transformer, ukusetyenziswa kwegesi kunye nokuhamba kweoyile ukufikelela kukhuseleko kubizwa ngokuba kukukhuselwa kwegesi.

(1) Ukhuseleko lwegesi ekhaphukhaphu: xa kukho isiphene okanye ukungaqheleki okuncinci ngaphakathi kwitransformer, ubushushu obugqithisileyo bendawo yesiphako bubangela ukwanda kweoyile okungaphelelanga, kwaye igesi ekwioyile yenza amaqamza ize ingene kwi-relay yegesi. Isenzo sokhuseleko lwegesi ekhaphukhaphu sithumela isignali yegesi ekhaphukhaphu.

(2) Ukhuseleko olunzima lwegesi: xa kuvela ingxaki enkulu kwitanki yetransformer, umsinga wengxaki mkhulu, kwaye i-arc ibangela ukuba ioyile yetransformer ibole ngobuninzi, nto leyo ebangela ukuba kubekho ukuhamba kwegesi kunye neoyile eninzi. Ingxaki yokungqubana kwempembelelo yenza igesi enzima ilandele isenzo sokukhusela, ithumele isignali yegesi enzima kunye nohambo lokuphuma, kwaye itransformer iyanqunyulwa.

(3) Ukhuseleko olunzima lwegesi lolona khuselo luphambili lokusilela kwangaphakathi kwetanki yepetroli, olunokubonakalisa ukusilela okuhlukeneyo kwangaphakathi kwetransformer. Xa itransformer isenzeka, kukho ukujika okumbalwa ukuze ijike i-short circuit, nangona umsinga wempazamo mkhulu kakhulu, kodwa kukhuseleko oluhlukeneyo oluveliswa kumsinga we-differential lusenokungabi mkhulu, ukhuseleko olungafaniyo lunokwala ukusebenza. Ke ngoko, kwiimpazamo zangaphakathi zetransformer, kuyimfuneko ukuthembela kukhuseleko olunzima lwegesi ukuze kususwe iimpazamo.

Umfanekiso

2, ukhuseleko loxinzelelo

Ukhuseleko loxinzelelo lukwalukhuseleko oluphambili kwiimpazamo zangaphakathi zetanki yetransformer. Ngokukhutshwa koxinzelelo kunye nokukhuselwa kotshintsho loxinzelelo, kusetyenziswa ukubonisa uxinzelelo lweoyile yetransformer.

3, ukhuseleko lobushushu kunye nenqanaba leoyile

Xa ubushushu betransformer bunyuka bufikelela kwixabiso lesilumkiso, ukhuseleko lobushushu luthumela isignali ye-alamu kwaye luqalise i-standby cooler.

Xa i-transformer ivuza ioyile okanye yehlisa inqanaba leoyile ngezinye izizathu, inqanaba leoyile liyakhuseleka kwaye kuthunyelwa isignali yesilumkiso.

4, ukhuseleko lokumisa konke olupholileyo

Xa zonke ii-cooler ze-transformer zisebenza, ubushushu be-transformer buya kunyuka. Ukuba aziphathwanga ngexesha, ubushushu be-insulation ye-transformer winding bunokonakala. Ke ngoko, xa zonke ii-cooler zisebenza, ukhuseleko luthumela isignali ye-alamu kwaye lukhuphe i-transformer emva kokulibaziseka ixesha elide.

Isine, ukhuseleko oluhlukileyo

Ukhuseleko lomahluko wetransformer lolona khuselo luphambili lomthamo wombane wetransformer, kwaye ububanzi bayo bokhuseleko yinxalenye ejikelezwe yitransformer yangoku ecaleni ngalinye. Kolu luhlu kwenzeka phakathi kwesekethe emfutshane, isekethe emfutshane ephakathi kunye nezinye iimpazamo, ukhuseleko lomahluko kwisenzo.

1, i-transformer inrush current

Umsinga wentsimi oveliswayo xa i-transformer iwiswa ubizwa ngokuba yi-field inrush current. Ubungakanani bomsinga we-inrush ovuselelayo bunxulumene nesakhiwo se-transformer, i-Angle yokuvala, umthamo, i-remanence ngaphambi kokuvala kunye nezinye izinto. Umlinganiselo ubonisa ukuba umsinga we-inrush uhlala uphindwe ka-2 ~ 6 womsinga olinganisiweyo, kwaye ubuninzi bungaphezulu ka-8 womsinga olinganisiweyo. Ngenxa yokuba umsinga we-inrush ungena kwi-transformer kuphela kwicala lokutshaja, uya kuvelisa umsinga omkhulu womahluko kwi-differential loop, nto leyo ebangela ukuba ukhuseleko lomahluko lungasebenzi kakuhle.

Umsinga wokungena uneempawu ezilandelayo: a. Ixabiso lomsinga wokungena likhulu kakhulu kwaye liqulathe icandelo elicacileyo le-aperiodic; B. I-waveform icacile kwaye ayiqhubeki; C, iqulathe icandelo elicacileyo le-harmonic ephezulu, ingakumbi icandelo lesibini le-harmonic; D. Umsinga wokungena wokungena uyancitshiswa.

Ngokweempawu ezingentla ze-inrush current, ukuze kuthintelwe i-inrush current ukuba ingabangela ukungasebenzi kakuhle kwe-transformer differential protection, le projekthi isebenzisa imigaqo emithathu: umxholo we-harmonic wesibini ophezulu, i-waveform asymmetry, i-waveform discontinuity Angle ukuze kufezekiswe ukutshixwa kwe-differential protection.

2. Umgaqo wesibini wokuqhoboshela i-harmonic

Eyona nto iphambili kwi-harmonic braking yesibini kukusebenzisa i-harmonic component yesibini ye-differential current ukugweba ukuba i-differential current yi-fault current okanye i-inrush current. Xa ipesenti ye-harmonic component yesibini kwi-fundamental component ingaphezulu kwexabiso elithile (ngesiqhelo yi-20%), i-differential current igwetywa njengebangelwa yi-inrush current, kwaye ukhuseleko lwe-differential luvaliwe.

Ke ngoko, okukhona umlinganiselo wesibini wokuqhobosheka kwe-harmonic umkhulu, kokukhona umlinganiselo wesibini wokuqhobosheka kwe-harmonic oqulethwe kwi-fundamental wave evumelekileyo uphezulu, kwaye kokukhona umphumo wokuqhobosheka usiba mbi.

3, ukhuseleko olukhawulezileyo lokwahluka

Xa kuvela impazamo enkulu ngaphakathi kwi-transformer kwaye i-fault current inkulu ngokwaneleyo ukuba ikhokelele kwi-CT saturation, i-CT secondary current ikwanazo nenani elikhulu lezinto ezihambelanayo. Ngokwenkcazo engentla, kusenokwenzeka ukuba ukhuseleko lomahluko luya kutshixwa okanye lulibaziseke ngenxa ye-harmonic braking yesibini. Oku kuya konakalisa kakhulu i-transformer. Ukusombulula le ngxaki, ukhuseleko lokwahlukana ngokukhawuleza ludla ngokuseta.

Into yokuqhekeza ngokukhawuleza eyahlukileyo ngokwenene yinto ephezulu eguquguqukayo yokukhusela umahluko wexesha elide. Ngokungafaniyo nento eqhelekileyo yokwahlulahlula, ibonisa ixabiso elisebenzayo lokuhamba komahluko. Nokuba i-waveform yokujikeleza komahluko injani, ubungakanani benxalenye ye-harmonic, ukuba nje ixabiso elisebenzayo lokuhamba komahluko lidlula ixabiso lokuseta lokuqhekeza isantya somahluko (ngesiqhelo liphezulu kunexabiso lokuseta lokukhusela komahluko), iya kuyisusa ngoko nangoko i-transformer, ngaphandle kokutshixa komsinga wokungena kunye nezinye iindlela zokutshixa.

Ezintlanu, ukhuseleko lokuxhasa i-transformer

Ukhuseleko oluphambili lwe-transformer luqaliswa ngokufutshane, kwaye ukhuseleko oluxhasayo lwe-transformer luyaqhubeka nokuqaliswa. Kukho iintlobo ezininzi zolungiselelo lokhuseleko oluxhasayo lwee-transformer. Apha, sizazisa ngokufutshane iintlobo ezimbini zokhuseleko oluxhasayo lwe-transformer, ezikukukhusela i-overcurrent evala i-voltage kabini kunye nokukhusela umhlaba.

1, ukutshixa koxinzelelo oluphindwe kabini phezu kokhuseleko lwangoku

Ukhuseleko lwe-compound voltage locking overcurrent lukhuseleko oluxhasayo lwempazamo ye-short circuit phakathi kwee-transformers ezinkulu neziphakathi. Zifanelekile kwii-step-up transformers, ii-system connection transformers kunye nee-step-down transformers ezikhuselekileyo kakhulu ukuba zingahlangabezani neemfuno zobuntununtunu. I-compound voltage eyenziwe yi-negative sequence voltage kunye ne-low voltage inokubonakalisa iimpazamo ezahlukeneyo kuluhlu lokhuseleko, inciphise ixabiso lokuseta lokhuseleko lwe-overcurrent, kwaye iphucule ubuntununtunu.

Ukhuseleko lwe-compound voltage overcurrent lwenziwe yi-compound voltage element, i-overcurrent element kunye ne-time element. I-access current yokhuseleko yi-secondary-PHASE TREE-PHASE CT current kwicala lendawo ye-transformer, kwaye i-access voltage yi-secondary three-phase PT voltage kwicala lendawo okanye kwamanye amacala e-transformer. Ukukhusela i-microcomputer, i-voltage yeli cala inokubonelelwa kwamanye amacala ngesoftware, ukuqinisekisa ukuba naliphi na icala lokugcinwa kwe-PT, lisenokusebenzisa i-compound voltage overcurrent protection. I-action logic iboniswe ngezantsi.

2, ukhuseleko lokumisa umhlaba nge-transformer

Ukhuseleko olungasemva lwesiphako sesekethe esifutshane sokumisa umhlaba se-transformer enkulu nephakathi ludla ngokuba: ukhuseleko lwe-zero sequence overcurrent, ukhuseleko lwe-zero sequence overvoltage, ukhuseleko lwe-gap njalo njalo. Oku kulandelayo kukwazisa okufutshane ngeendlela ezintathu ezahlukeneyo zokumisa umhlaba ngokusekelwe kwindawo engathathi cala.

(1) Ingongoma engathathi cala isekelwe ngqo

Kwiitransformers ezine-voltage eyi-110kV kwaye ngaphezulu kwendawo engathathi cala isekelwe ngqo, ukhuseleko lwangoku oluyi-zero-sequence kufuneka lubekwe ecaleni kwenkqubo yokumisa umbane ophezulu ukuze lubonise isiphene sokumisa umbane. Kwiitransformers ezisekelwe ngqo kumacala aphezulu naphakathi, ukhuseleko lwangoku oluyi-zero-sequence kufuneka lube kwicala lebhasi nganye esecaleni.

Umgaqo wokhuseleko lwangoku lwe-zero sequence ufana nowokhuseleko lolandelelwano lwe-line zero sequence, jonga umba wama-30. Umsinga we-zero sequence unokufumaneka kumsinga we-CT wesibini wenqaku elingathathi cala, okanye kumsinga we-CT wesibini wesigaba sesithathu secala lendawo. I-voltage ye-zero sequence eqhagamshelwe kwi-element yecala inokufumaneka kwi-voltage ye-PT opening triangle yecala lendawo okanye kwi-voltage yesibini yesigaba sesithathu yecala lendawo. Kwisixhobo sokukhusela i-microcomputer, ikakhulu sebenzisa indlela ezenzelayo.

Kwiitransformer ezinkulu ezinee-twing ezintathu, ukhuseleko lwangoku olune-zero-sequence lunokuba ngamabakala amathathu. Kukho icala kwicandelo I nelesi-II, kwaye akukho icala kwicandelo III. Icandelo ngalinye ngokubanzi linokulibaziseka kwamabakala amabini, kunye nokulibaziseka okufutshane kokunciphisa uluhlu lwempazamo (ibhasi yokutsiba okanye iswitshi yendawo), kunye nokulibaziseka okude ukususa itransformer (iswitshi yokutsiba emacaleni amathathu). Uqwalaselo oluthile lokhuseleko luxhomekeke kwimeko yokwenyani.

Njengoko kubonisiwe kumfanekiso, emva kokusebenza kokhuselo lwangoku lwe-zero-sequence direction kwicandelo I okanye II, i-t1 okanye i-T3 bus okanye iswitshi yendawo ene-short delay kufuneka iqale itshixwe ukuze kuncitshiswe ububanzi bempembelelo ye-fault. Ukuba ubungakanani be-fault busekho, i-transformer kufuneka inqunyulwe nge-t2 okanye i-T4 three-way switch ene-long delay. Icandelo III elingena-direction, i-transformer isuswa ngokuthe ngqo ngokulibaziseka.

(2) indawo engathathi cala ayisekelwanga

Umsinga we-zero sequence udlula kwindawo engathathi hlangothi ye-transformer ukuze wenze i-zero sequence loop. Nangona kunjalo, ukuba zonke iindawo ezingathathi hlangothi ze-transformer zisekelwe, umsinga we-short-circuit kwindawo yokumisa umhlaba uya kusasazwa kwi-transformer nganye, nto leyo eya kubangela ukuba uvakalelo lokhuseleko lwe-zero-sequence overcurrent lunciphe. Ke ngoko, ukuze kuncitshiswe umsinga we-zero-sequence kuluhlu oluthile, inani lee-transformers ezisekelwe kwindawo engathathi hlangothi liyalawulwa.

Kwi-transformer engagungqiyo, kufuneka kulungiselelwe ukhuseleko lwe-voltage olungena-zero ukuze kuthintelwe umonakalo we-transformer ogqithisileyo obangelwa yi-gap arc kwindawo yempazamo xa kuvela impazamo yokugungqiyo.

I-transformer egqunyiweyo ngokupheleleyo ngenxa yenqanaba layo eliphezulu lokugquma le-neutral point, xa inkqubo isenzeka i-grounding fault, ukhuseleko lokuqala lwangoku lwe-zero-sequence ukususa i-neutral point grounding transformer, ukuba i-fault isekhona, kwaye emva koko i-zero-sequence voltage protection ukususa i-neutral point ungrounded transformer.

(3) Ingongoma engathathi cala isekelwe kumsantsa wokukhupha

Zonke ii-transformer ze-hV zi-semi-insulated, kwaye i-insulation ye-neutral coil emhlabeni ibuthathaka kunezinye iindawo. I-neutral insulation ithambekele ekuqhekekeni. Ke ngoko, kufuneka ulungiselele ukhuseleko lwe-clearance.

Indima yokukhusela isithuba kukukhusela indawo engathathi cala yokhuseleko lokufakelwa kwe-transformer engagungqiyo.

Njengoko kubonisiwe, kufakwa umsantsa wokuqhekeka phakathi kwendawo engathathi cala yetransformer nomhlaba. Xa iswitshi yokuzihlukanisa nomhlaba ivaliwe, itransformer isekelwe ngqo kwaye kufakwa ukhuseleko olungaphezulu kolandelelwano olungenanto. Xa iswitshi yokuzihlukanisa yomhlaba isusiwe, itransformer isekelwe ngaphaya komsantsa ize ifakwe kukhuseleko lwesithuba.

Ukhuseleko lwesithuba lufumaneka ngokusebenzisa i-gap current 3I0 ehamba kwindawo engathathi cala ye-transformer kunye ne-opening triangle voltage 3U0 yebhasi PT njenge-criterion.

Ukuba indawo engathathi cala kwindawo apho kukho impazamo iphakanyisiwe, ukuqhekeka kwesithuba, okubangela ukuba kubekho umsinga omkhulu wesithuba esingu-3I0, ngeli xesha, isenzo sokukhusela isithuba, emva kokulibaziseka kokususa i-transformer. Ukongeza, xa inkqubo inesiphako sokumisa umhlaba, umsebenzi wokumisa umhlaba wesithuba esingathathi cala, i-transformer ayisebenzisi landelelwano, kuqala inqumle i-transformer yokumisa umhlaba yesithuba esingathathi cala. Emva kokuba inkqubo ilahlekelwe yindawo yomhlaba, ukuba impazamo isekhona, i-voltage evulekileyo ye-bus PT 3U0 iya kuba nkulu, kwaye ukhuseleko lwesithuba luya kusebenza ngeli xesha.

Umthombo: Ipulpiti yamandla