Amadivaysi okuzivikela aphezulu (SPDs) adingeka ukuthi ahlolwe ngaphansi kwemifudlana yokungena emfuthweni ngokuyinhloko namafomu omhlaba we-8 / 20 ms no-10 / 350 ms. Kodwa-ke, ngokuthuthukiswa kwemikhiqizo ye-SPD, ukusebenza nokulwa nokukwazi ama-SPD ngaphansi kwalezi zivivinyo zokuhlolwa ezijwayelekile kudinga uphenyo oluningi. Ukuze uphenye futhi uqhathanise ikhono lokumelana lama-SPD ngaphansi kwe-8 / 20 ms kanye ne-10 / 350 ms currents impulse, ukuhlolwa kwenziwa ngezinhlobo ezintathu ze-metal-oxide varistors (MOVs) ejwayelekile ezisetshenziselwa ama-SPDs ekilasini. Imiphumela ibonisa ukuthi ama-MOV anamandla amkhawulo aphakeme angcono ukumelana nokukwazi ukubhekana nokusebenza kwe-8 / 20ms yamanje, ngenkathi isiphetho ngaphansi kwe-10 / 350ms yokufaka umfutho wamanje kufinyelela. Ngaphansi kwe-10 / 350 ms wamanje, ukuhluleka kwe-MOV kuhlobene nomthamo we-unit ngayinye ngokwemibono eyodwa. Ukuphahla kuyindlela enkulu yokulimala ngaphansi kwe-10 / 350ms yamanje, engachazwa njengecala elilodwa le-encapsulation ye-MOV eplastiki futhi ishidi le-electrode likhishwa. Ukukhishwa kwezinto ZnO, okubangelwa i-flashover emkhatsini we-electrode sheet kanye ne-ZnO surface, kubonakala eduze kwe-electrode ye-MOV.
Amadivaysi okuzivikela aphezulu (SPDs) axhunyiwe kuma-powervoltage systems, ama-telecommunication kanye namanethiwekhi amanethiwekhi kudingeka ahlolwe ngaphansi kwezidingo zamazinga we-IEC nama-IEEE [1-5]. Ukucabangela indawo kanye nokukhanya okungenzeka okwamanje kungase kuhlupheke, ama-SPD anjalo adingeke ahlolwe ngaphansi kwemifudlana yokungena emzimbeni ikakhulukazi ngama-waveforms we-8 / 20 ms no-10 / 350 ms [4-6]. Isimo somswakama samanje se-8 / 20 ms isetshenziselwa ukulinganisa umfutho wombane [6-8]. Ukukhishwa kwamagama okwamanje (In) kanye nokukhishwa kwamanje okuphezulu (Imax) kwe-SPDs kokubili kuchazwe nge-8 / 20 ms current impulse yamanje [4-5]. Ngaphezu kwalokho, i-8 / 20 ms impulse yamanje isetshenziselwa kabanzi ukuvuthwa kwe-SPD kanye nokuhlolwa komsebenzi [4]. I-10 / 350ms yomsindo we-impulse yamanje isetshenziselwa ukulingisa ukukhanya okuqondile ukubuyela kwesifo samanje [7-10]. Lolu hlobo lwamafilimu luhlangabezana nemingcele ye-current impulse yokukhipha ukuhlolwa kwe-class I SPD, okusetshenziselwa ikakhulukazi ukuhlolwa komsebenzi we-class I SPDs [4]. Phakathi nohlobo lokuhlolwa kohlobo lwe- [4-5], inombolo ecacisiwe yemigudu yokucindezela kuyadingeka ukuthi isebenze kuma-SPDs. Isibonelo, ama-8 / 20 ms currents amashumi ayishumi nesishiyagalolunye namagundane amahlanu we-10 / 350 ms okudingekayo ekuhlolweni komsebenzi we-class I SPDs [4]. Kodwa-ke, ngokuthuthukiswa kwemikhiqizo ye-SPD, ukusebenza nokulwa nokukwazi ama-SPD ngaphansi kwalezi zivivinyo zokuhlolwa ezijwayelekile kudinga uphenyo oluningi. Iziphenyo zangaphambilini zivame ukugxila ekusebenzeni kwe-MOV ngaphansi kwe-8 / 20 ms current impulse yamanje [11-14], ngenkathi ukusebenza ngaphansi kokuphindaphindiwe kwe-10 / 350 ms umxhwele wamanje akuphenywanga kahle. Ngaphezu kwalokho, i-class I SPDs, efakwe emaphoyiseni ekuchaseni okuphezulu ezakhiweni nasezintweni zokusabalalisa, zisengozini kakhulu ekushayweni kwemibani [15-16]. Ngakho-ke, ukusebenza futhi ukumelana nokukwazi kwe-SPDs yeklasi ngaphansi kwe-8 / 20 ms kanye ne-10 / 350 ms currents impulse ezidingekayo ukuze ziphenywe. Leli phepha lihlola ngokuphambene nokukwazi ukuma amandla e-SPDs ekilasini ngaphansi kwe-8 / 20 ms kanye ne-10 / 350 ms impulse currents. Izinhlobo ezintathu zama-MOV ajwayelekile asetshenziselwa ama-SPD ekilasini I-adopt for analysis. I-amplitude yamanje nenombolo yezimpendulo zilungiswa ukuhlolwa okunaminingana. Ukuqhathaniswa kwenziwa ekunqandeni ikhono lama-MOV ngaphansi kwezinhlobo ezimbili zamagagasi okucindezela. Imodi yokuhluleka yamasampuli we-MOV ahlulekile ngemva kokuhlolwa futhi kuhlaziywa.
Izinhlobo ezintathu zama-MOV ajwayelekile asetshenziselwa ama-SPD esiklasini I amkelwe ekuhlolweni. Ngolunye uhlobo lwe-MOV, amasampuli e-12 eyenziwe yi-EPCOS athathwa ngaphansi kwezinhlobo ezine zokuhlola. Imingcele yabo eyisisekelo iboniswa ku-ITHEBULA I, lapho Imela khona ukukhishwa kwamagama okukhulunywa ngokusemthethweni kwe-MOV ngaphansi kwe-8 / 20μs impulse, i-Imax imelela ukukhishwa okuphezulu okuphezulu ngaphansi kwe-8 / 20μs impulse, ngimelela ukukhishwa okukhulu okukhona ngaphansi kwe-10 / 350μs, okushiwo ngu-UDC1mA i-voltage ye-MOV elinganiswa ngaphansi kwe-1 mA DC yamanje, i-Ur imela amandla we-MOV asele ngaphakathi.
I-Fig. I-1 ikhombisa umshini wokukhiqiza wamanje ongasetshenziselwa ukushintshwa ukuze kukhishwe izimpendulo zamanje ze-10 / 350 ms no-8 / 20. I-coarson ye-Pearson iyakwamukelwa ukulinganisa imifudlana yomsindo kuma-MOV ahlolwe. Umhlukanisi wendiza ene-ratio ye-14.52 isetshenziselwa ukukala izintambo zokuhlala. I-oscilloscope yedijithali ye-TEK DPO3014 iyakwamukelwa ukurekhoda amafomu okuzama ukuhlola.
Ngokwesilinganiso sokuhlola se-SPD [4], i-amplitudes eyamukelwe i-8 / 20 ms yamanje ihlanganisa i-30kA (0.75Imax) ne-40kA (Imax). Ama-amplitudes avunyelwe i-10 / 350 ms wamanje afaka i-0.75Iimp no-Iimp. Ukubhekisela kokuhlolwa komsebenzi we-MOVs [4], izimpendulo eziyishumi nanhlanu ze-8 / 20ms zisetshenziselwa amasampula e-MOV, futhi isikhathi esiphakathi kwezinguquko ngu-60. Ngakho-ke, umjikelezo wezinqubo zokuhlola uboniswa kuFi. 2.
Inqubo yokuhlola ingachazwa ngokuthi:
(1) Izilinganiso zokuqala: Amasampuli e-MOV abonakala nge-UDC1mA, i-Uri, nezithombe ekuqaleni kokuhlolwa.
(2) Faka izicelo eziyishumi nanhlanu: Lungisa umshini wokukhiqiza wamanje wokufaka umfutho wokukhipha okwamanje okudingekayo. Izimpikiswano eziyishumi nesishiyagalolunye nesigaba se-60 s isetshenziswa kusampula se-MOV ngokulandelanayo.
(3) Qopha amafomu wokulinganisa okulinganiselwe we-currents MOV kanye neminyango ngemuva kwesicelo ngasinye sokusikisela.
(4) Ukuhlolwa okubukwayo nokulinganisa ngemva kokuhlolwa. Hlola ubuso be-MOV yokukhishwa noma ukugcoba. Linganisa i-UDC1mA ne-Uri ngemva kokuhlolwa. Thatha izithombe ze-MOV ewonakele ngemuva kokuhlolwa. Indlela yokudlula yokuhlolwa, ngokusho kwe-IEC 61643-11 [4], idinga ukuthi kokubili amarekhodi wamandla kanye namanje, kanye nokuhlola okubukwayo, ngeke kubonise ukuthi kuboniswa ukukhishwa noma ukugcoba ama-sampuli. Ngaphezu kwalokho, i-IEEE Std. U-C62.62 [5] uphakamise ukuthi i-Uri yokulinganisa i-posttest (i-MOV yokunciphisa ama-voltages ku-In) ngeke iguquke ngaphezu kwe-10% ukusuka ku-Uri elinganiselwe. I-Std. I-IEC 60099-4 [17] idinga nokuthi i-UDC1mA akufanele ihluke ngaphezu kwe-5% ngemva kokuhlolwa kokucindezela.
- Ukukwazi ukumelana ngaphansi kwe-8 / 20 ms impulse yamanje
Kulesi sigaba, ama-8 / 20 ms currents impulse am amplitudes we-0.75Imax ne-Imax asetshenziselwa amasampuli e-SPD ngokulandelana. Ukushintsha kwesilinganiso se-posttest kulinganiswa u-UDC1mA ne-Ur ichazwa ngokuthi:
lapho, u-Ucr ubonisa ukushintsha kwesilinganiso samagugu alinganisiwe. Uat imelela inani elilinganiselwe ngemva kokuhlolwa. Ubt ubonisa inani elilinganiselwe ngaphambi kokuhlolwa.
I-3.1 Imiphumela ngaphansi kwe-8 / 20 ms current impulse yamanje ngenani le-0.75Imax
Imiphumela yokuhlolwa yezinhlobo ezintathu ze-MOV ngaphansi kwezingu-14 ze-8 / 20 ms currents impulse ngezinga eliphakeme le-0.75Imax (30 kA) iboniswa ku-ITHEBULA II. Umphumela wohlu lwawo wonke uhlobo lwe-MOV luyisilinganiso samasampuli amathathu afanayo.
ITHEBULA II
Imiphumela ngaphansi kwe-8 / 20 ms currents impulse currents nge-30 kA phezulu
Kungabonakala kusuka ku-TABLEII ukuthi emva kwezinsuku eziyishumi nanhlanu ze-8 / 20 ms ukusetshenziselwa kuma-MOV, izinguquko ze-UDC1mA ne-Ur zincane. I "Pass" yokuhlolwa okubukwayo akusho ukuthi umonakalo obonakalayo kuma-MOV ahlolwe. Ngaphezu kwalokho, kungabonakala ukuthi ngokukhuphuka kweMVV yokunciphisa amandla, i-Ucr iba yincinjana. Efana ne-Ucr iyona encane kunazo zonke ze-V460 uhlobo lwe-MOV. Kungaphetha ngokuthi lezi zinhlobo ezintathu ze-MOV zingadlulisa wonke ama-8 / 20 ms impulse nge-30 kA phezulu.
I-3.2 Imiphumela ngaphansi kwe-8 / 20 ms current impulse yamanje ngenani le-Imax
Uma sicabanga ngemiphumela yokuhlola ngenhla, ubukhulu be-8 / 20 ms wamanje bukhuphukele ku-40 kA (Imax). Ngaphezu kwalokho, inani lemifuduko lenyuke libe yizinkulungwane ezingamashumi amabili ze-V460 uhlobo lwe-MOV. Imiphumela yokuhlola iboniswa ku-ITHEBU III. Ukuze uqhathanise ukumiswa kwamandla kulezi zinhlobo ezintathu ze-MOV, i-Ea / V isetshenziselwa ukumela amandla amandla we-unit ngayinye ngokwemilinganiso yezinyathelo eziyishumi nambili noma ezingamashumi amabili. Lapha, "isilinganiso" sithathwa njengombana ukunamandla kwamandla ku-MOVs kuhluke kakhulu ngaphansi kwesisindo ngasinye.
ITHEBU III
Imiphumela ngaphansi kwe-8 / 20 ms currents impulse currents nge-40 kA phezulu
Kungabonwa kusukela kuTHEBLELE III ukuthi lapho ukuphakama kwamanje kukhishwa ku-40 kA, i-Ucr ye-UDC1mA isuka ngaphezu kwe-5% ye-V230 ne-V275, nakuba ukuguqulwa kwamandla we-MOV asele kusekhona phakathi kwe-10%. Ukuhlolwa okubukwayo akubonisi ukulimala okubonakalayo kuma-MOV ahlolwe. I-ForV230 ne-V275 uhlobo lwe-MOVs, i-Ea / V isho amandla amandla we-unit ngayinye ne-average of impulses ayishumi nanhlanu. I-EA / V ye-V460 imelela amandla amancane ngeyunithi yeyunithi ngokulinganisela kwemiqondo engamashumi amabili. I-TABLE III ibonisa ukuthi ama-MOV anemiphawulo ephakeme ephakeme (V460) anama-A / V amakhulu kunama-MOV anamandla okunciphisa amancane (V275 ne-V230). Ngaphezu kwalokho, ngokusebenza okuphindaphindiwe ngokuphindaphindiwe ku-V460, i-unit absorption ngayinye ivolumu (E / V) iyanda kancane kancane, njengoba kuboniswe kuFi. 3.
Ngakho-ke, kungaphetha ngokuthi i-V230 ne-V275 uhlobo lwe-MOVs ayikwazanga ukumelana nezimpikiswano eziyishumi nanhlanu ze-8 / 20ms ngokuphakama kwe-Imax, kanti i-V460 uhlobo lwe-MOV ingakwazi ukumelana nokukhishwa kwamanje okuphezulu kuze kufike ku-20 impulses. Lokhu kusho ukuthi ama-MOV anamandla amkhawulo aphakeme angcono ukumelana nokukwazi ukubeka amandla ngaphansi kwe-8 / 20ms yamanje.
I-4. Ikhono lokumelana ngaphansi kwe-10 / 350 ms current impulse yamanje
Kulesi sigaba, ama-10 / 350 ms currents impulse am amplitudes we-0.75Iimp ne-Iimp asetshenziselwa amasampuli e-SPD ngokulandelana.
I-4.1 Imiphumela ngaphansi kwe-10 / 350 ms current impulse yamanje ngenani le-0.75Iimp
Njengoba i-Iimp yezinhlobo ezintathu ze-MOV ihlukile, ama-10 / 350 ms currents ane-amplitude ye-4875A asetshenziselwa i-V230 ne-V275, futhi impuls nge-amplitude ye-4500 A isetshenziswa ku-V460. Ngemuva kokusebenzisa ama-currents ayishumi namashumi ayisishiyagalolunye, izinguquko ze-UDC1mA ne-Ur kuma-MOV ahlolwe ziboniswa ku-ITHEBU IV. I-ΣE / V isho ukufakwa kwe-E / V yezimpendulo ezifakiwe.
Kungabonakala kusuka eThebula IV ukuthi emva kokusebenzisa ama-10 / 350 ms currents ms ngezinga eliphakeme le-0.75Iimp, i-V230 ingadlula ukuhlolwa, kanti ushintsho lwe-UDC1mA ye-V275 luhluke ngaphezu kwe-5%. Ukuzikhukhumeza nokuncipha okuncane kuvele futhi ku-plastic encapsulation ye-V275. Isithombe se-V275 esinamahlumela amancane siboniswa ku-Fig. 4.
Kuhlobo lwe-V460 MOV, ngemuva kwe-10 / 350 ms impulse yesishiyagalolunye nge-4500A isetshenzisiwe, i-MOV iphukile futhi amanani alinganisiwe namashini omumo wamanje awavamile. Ukuqhathanisa, amanani alinganiselwe namanothi wamanje wamagesi ngaphansi kwe-10 / 350 ms impulse ku-V460 aboniswa kuFi. 5.
I-Fig. 5. Amandla wokulinganisa namanothi wamanje we-V460 ngaphansi kwe-10 / 350 ms impulse
I-V230 ne-V275, ΣE / V yi-summation ye-E / V yemizamo eyishumi nanhlanu. Ku-V460, ΣE / V yi-summation ye-E / V yezimpendulo ezingu-8. Kungabonakala ukuthi nakuba i-Ea / V ye-V460 ingaphezulu kune-V230 ne-V275, inani le-ΣE / Vof V460 liphansi kakhulu. Nokho, i-V460 yabhekana nomonakalo omkhulu kakhulu. Lokhu kusho ukuthi kumthamo weyunithi we-MOV, ukuhluleka kwe-MOV ngaphansi kwe-10 / 350 ms yamanje akuhlobene ne-total energy absorb (Σ E / V), kodwa kungenzeka ukuthi ihlobene kakhulu namandla angenwe ngaphansi kwesisindo esisodwa (Ea / V ). Kungaphetha ngokuthi ngaphansi kwe-10 / 350 ms current impulse, i-V230 ingamelana nezimpendulo ezingaphezu kwe-MOVs ye-V460. Lokhu kusho ukuthi ama-MOV anemikhawulo ephansi yokunciphisa ingcono ukumelana namandla ngaphansi kwe-10 / 350 ms yamanje, ephikisana nesiphetho ngaphansi kwe-8 / 20 ms current impulse yamanje.
I-4.2 Imiphumela ngaphansi kwe-10 / 350 ms current impulse yamanje ngenani le-Iimp
Uma ubukhulu be-10 / 350 ms yamanje bukhuphukela ku-Iimp, wonke ama-MOV avivinywe akakwazanga ukudlulisa izifiso eziyishumi nanhlanu. Imiphumela ngaphansi kwe-10 / 350 ms currents impulse nge-ampimpitude ye-Iimp iboniswa ku-ITHEMU V, lapho "Inombolo yokumelana nokucindezela" kusho inani elingenayo impendulo yokuthi i-MOV ingakwazi ukumelana ngaphambi kokuqhekeka.
Kungabonwa kusuka eThebula V ukuthi i-V230 ne-Ea / V ye-122.09 J / cm3 ingamelana nezimpikiswano eziyisishiyagalombili ze-10 / 350 ngenkathi i-V460 ne-Ea / V ye-161.09 J / cm3 idlulela kuphela izimpendulo ezintathu, nakuba inani eliphakeme lamukelwa I-V230 (6500 A) iphakeme kuneleyo ye-V460 (6000 A). Lokhu kuvumela isiphetho sokuthi ama-MOV anemiphawulo ephakeme ekhungethwe kalula kalula ngaphansi kwe-10 / 350 ms yamanje. Lesi simo singachazwa ngokuthi: amandla amakhulu athathwa yi-10 / 350 ms wamanje azofakwa kuma-MOV. Ku-MOV ene-voltage ephakeme ephansi kwe-10 / 350 ms wamanje, amandla amaningi azofakwa emthamo weyunithi we-MOV kunokuba kuma-MOV anamandla amancane okunciphisa amandla, futhi ukungena kwamandla ngokweqile kuzoholela ekuhlulekeni kwe-MOV. Noma kunjalo, indlela yokuhluleka ngaphansi kwe-8 / 20 ms yamanje idinga uphenyo olwengeziwe.
Ukuhlola okubonakalayo kubonisa ukuthi ifomu elifanayo lokulimala liyabonakala kulezi zinhlobo ezintathu zama-MOV ngaphansi kwe-10 / 350 ms yamanje. Olunye uhlangothi lwe-MOV encapsulation encapsulation kanye nekhasi le-electrode le-rectangular. Ukukhishwa kwempahla ye-ZnO kubonakala eduze kwekhasi le-electrode, elibangelwa i-flashover phakathi kwe-MOV electrode ne-ZnO surface. Isithombe se-V230 sibonisiwe ku-Fig. 6.
5. Isiphetho
Ama-SPD adingeka ukuthi avivinywe ngaphansi kwemifudlana yokungena emzimbeni ikakhulukazi ngama-waveforms we-8 / 20 ms no-10 / 350 ms. Ukuze uphenye futhi uqhathanise ikhono lokumelana lama-SPD ngaphansi kwe-8 / 20 ms kanye ne-10 / 350 ms currents impulse, ukuhlolwa okuhlukahlukene kwenziwa nge-8 / 20 ms (Imax) no-10 / 350 ms (Iimp) waveform form , kanye nama-amplitudes we-0.75Imax no-0.75Iimp. Izinhlobo ezintathu zama-MOV ajwayelekile asetshenziselwa ama-SPD ekilasini I-adopt for analysis. Ezinye iziphetho zingadonselwa.
(1) I-MOV enamandla amkhawulo aphakemeyo angcono ukumelana nokukwazi ukubhekana nokusebenza kwe-8 / 20ms yamanje. I-V230 ne-V275 uhlobo lwe-MOVs ayikwazanga ukumelana nezimpikiswano ezingu-8 / 20ms ngenani eliphakeme le-Imax, kanti uhlobo lwe-V460 i-MOV lungadlulisa izimpendulo ezingamashumi amabili.
(2) I-MOV enomthamo wokunciphisa ophansi ingcono ukumelana namandla ngaphansi kwe-10 / 350 ms yamanje. Uhlobo lwe-V230 MOV lungamelana nezimo eziyisishiyagalombili ze-10 / 350 msingi we-Iimp, kuyilapho i-V460 idlulela kuphela izimpendulo ezintathu.
(3) Ngokucabangela umthamo weyunithi we-MOV ngaphansi kwe-10 / 350 ms wamanje, amandla angenwe ngaphansi kwesisindo esisodwa angase ahlobene nokuhluleka kwe-MOV, esikhundleni sokushiswa kwamandla ngaphansi kwamandla onke.
(I-4) Ifomu elimele lomonakalo liyabonakala ngezinhlobo ezintathu zama-MOV ngaphansi kwe-10 / 350 ms currents. Olunye uhlangothi lwe-MOV encapsulation encapsulation kanye nekhasi le-electrode le-rectangular. Ukukhishwa kwezinto ZnO, okubangelwa i-flashover phakathi kwephepha le-electrode ne-ZnO surface, kubonakala eduze kwe-MOV electrode.