Dalilin da Yasa BC Solar Cells Ke Gudanar da Inuwa Da Kyau Kuma Suyi Sanyi Hot Spots
Teburin Abubuwan Ciki
Gabatarwa
Inuwa matsala ce ta gama gari a shigarwar PV na ainihi.
Inuwar bishiyoyi, sandunan wutar lantarki, ƙura, najasar tsuntsaye, dusar ƙanƙara, ko ma kusurwoyin hawa panel marasa daidaito na iya haifar da inuwa ta ɓangare. Inuwa ba kawai tana rage fitowar panel ba, tana iya haifar da wani babban matsala: wuraren zafi.
A cikin 'yan shekarun da suka gabata, kwayoyin hasken rana na BC sun jawo hankali sosai a cikin rufin rufi, PV na baranda, da kuma manyan kayayyaki. Babban dalili shine: Kwayoyin hasken rana na BC yawanci suna ba da juriya ga inuwa, kuma yanayin zafi a wuraren da suke da zafi yakan kasance ƙasa da ƙasa a ƙarƙashin inuwa.
A SNEC, sau da yawa kuna ganin masana'antun suna rufe wani ɓangare na layin kwayoyin hasken rana sannan su yi amfani da tsayin ruwa daga famfo don nuna juriyar inuwa na kayayyakin BC.
Don haka me yasa kwayoyin BC suke da wannan fa'ida? Menene ilimin kimiyyar lissafi a bayansa?
Bari mu gwada bayyana shi cikin kalmomi masu sauƙi.
Me yasa Inuwa ke haifar da Wuraren Zafi
Me yasa inuwa ke haifar da wuraren zafi?
Kwayoyin hasken rana a cikin wani PV module yawanci ana haɗa su a jere.
Tsarin jere yana da siffa ɗaya: dole ne wutar lantarki ta kasance iri ɗaya a ko'ina.
Wannan yana nufin cewa wutar lantarki ta dukan layin tana dogara ne da madauki gaba ɗaya. Lokacin da kowane kwayar hasken rana ya sami cikakken haske, kowannensu yana samar da wutar lantarki kuma duk suna cikin yanayi mai daidaito.
Amma idan tantanin halitta ɗaya ya sami inuwa, halin yanzu da aka samar da hoto zai iya raguwa. Idan har yanzu duka layin yana buƙatar ɗaukar babban halin yanzu, wannan tantanin da aka yi inuwa zai iya turawa zuwa baya ta hanyar sauran tantanin da ba a yi inuwa ba. A wannan lokacin ya daina zama tushen wuta kuma ya zama mai amfani da wuta.
Don inuwa ta wani ɓangare, tantanin da aka yi inuwa baya daina samar da wuta gaba ɗaya. Yankin da ba a yi inuwa ba har yanzu yana samar da ɗan halin yanzu na hoto. Don haka abin da ya kamata ya gudana ta hanyar rushewar baya, hanyar zubewa, ko hanyar wucewa ba shine cikakken halin yanzu na layin ba, amma bambanci tsakanin halin yanzu na layin da halin yanzu da wannan tantanin zai iya samarwa.
Wannan bambanci ana iya kiransa da rashin daidaituwa na halin yanzu:
Imismatch = Istring - Igenerate
Don haka wutar lantarki ta wurin zafi za a iya rubuta ta a takaice:
Photspot ≈ ∣Vrev∣ × Imismatch
wanda shine:
Photspot ≈ ∣Vrev∣ × (Istring - Igenerate)
Wannan dabara tana nuna abu ɗaya mai mahimmanci: a daidai halin yanzu na layin, mafi girman wutar lantarki ta baya, mafi yawan wutar da tantanin da aka yi inuwa ke watsawa, kuma mafi zafi wurin zafi yake.
Don haka daya daga cikin mabuɗan tsayayya da wuraren zafi shine:
yadda ake rage wutar lantarki mai juyawa akan tantanin da aka inuwa kuma a sanya dumama ta zama daidai.
Wannan shi ne ainihin inda BC cells suke haskakawa.
Yadda BC Cells suka bambanta a Tsari
Yaya BC cell ta bambanta a tsari daga tantanin al'ada?
Tantunan siliki na al'ada yawanci suna amfani da tsarin haɗin gaba da baya.
A taƙaice:
Gaba yana da layukan grid da busbars, kuma haske yana shiga daga gaba;
Ana samar da wutar lantarki a cikin tantanin sannan a tattara ta ta hanyar na'urorin gaba da baya.
Tantanin BC, ma'ana Back Contact, yana da fasali guda ɗaya:
duka na'urorin lantarki masu inganci da marasa inganci suna kan bayan tantanin, babu layukan grid na ƙarfe a gaba.
Wannan yana ba da fa'idodi kai tsaye guda biyu:
Babu inuwar layukan grid a gaba, don haka ƙarin wurin karɓar haske;
Ana iya gina na'urorin lantarki na baya zuwa tsarin interdigitated, don haka tattara wutar lantarki ya zama daidai.
Hoto 1 Tsarin sashi na BC cell.
Tushen: Calcabrini, A., Procel Moya, P., Huang, B., Kambhampati, V., Manganiello, P., Muttillo, M., Zeman, M., & Isabella, O. (2022). Low-breakdown-voltage solar cells for shading-tolerant photovoltaic modules. Cell Reports Physical Science, 3(12), 101155. https://doi.org/10.1016/j.xcrp.2022.101155
Bayan BC cell yana ɗauke da yankuna p da yankuna n da yawa da aka haɗa. Tsakanin waɗannan yankuna akwai gajerun PN junctions da yawa masu nauyi. Daga mahangar kewayawa, ba ya zama kamar babban diode guda ɗaya, amma kamar ƙananan diodes da yawa a layi daya. A ƙarƙashin juyar da baya, waɗannan rarraba PN junctions na iya samar da hanyar tafiyar da baya mafi daidaituwa.
Saboda waɗannan PN junctions na baya gajeru ne kuma suna da nauyi a cikin gida, suna iya shiga rushewar baya a ƙaramin ƙarfin lantarki na baya.
Tabbas, wannan ya dogara da takamaiman sigogin ƙira na BC cell.
Misali, ƙaramin tazarar da ke tsakanin yankin p da yankin n, mafi ƙarfin filin gida, kuma yawanci yana da sauƙi a samar da ƙaramin ƙarfin juyawa baya. Amma hakan na iya kawo musaya a cikin zubewa da juriya na shunt. Don haka juriyar inuwa ta tantanin BC ba ƙayyadadden ƙima ba ce. Yana da alaƙa da takamaiman tsarin tantanin halitta, ƙirar bayan fage, girman tazara, yawan doping, ingancin passivation, da tsarin masana'anta.
Dalilin da yasa Kwayoyin BC ke rasa ƙarancin Wuta a ƙarƙashin Inuwa
Me yasa kwayoyin BC ke rasa ƙarancin wuta bayan inuwa?
Lokacin da wani bangare na panel ya yi inuwa, igiyar jeri tana tura tantanin da aka yi inuwa zuwa juyawa baya. Yayin da inuwa ta tsananta, jimillar ƙarfin lantarki a kan wannan ɓangaren yana ci gaba da raguwa.
A cikin na'urori na gargajiya, ana sanya diode na kewayawa a layi daya a kan wani sashe na jeri. Diode na kewayawa ba ya kunna ta hanyar mai sarrafawa. Na'urar da ba ta aiki ce. Ko tana gudana ya dogara ne kawai akan ƙarfin lantarki a kanta. Lokacin da jimillar ƙarfin lantarki na wannan ɓangaren ya zama mara kyau sosai, diode na kewayawa yana samun gaba kuma yana kunna kai tsaye.
Yanayin kunnawa ana iya rubuta shi kamar:
Vsubstring ≤ -Vf
Vsubstring shine jimlar wutar lantarki na substring ɗin da bypass diode ke karewa;
Vf shine faɗuwar wutar lantarki ta gaba na bypass diode.
Ga substring, jimlar wutar lantarki ɗin za a iya fahimta kamar:
Vsubstring = ∑Vunshaded + ∑Vshaded
inda:
Kwayoyin da ba a inuwa suna samar da wutar lantarki ta gaba;
Kwayoyin da aka inuwa suna juyar da baya kuma suna samar da wutar lantarki mara kyau.
Yanayin kunna bypass diode za a iya karanta shi kamar:
∣∑Vshaded∣ ≥ ∑Vunshaded + Vf
A wasu kalmomi:
Jimlar wutar lantarki mara kyau na kwayoyin da aka inuwa dole ne ta wuce jimlar wutar lantarki ta gaba na sauran kwayoyin da ba a inuwa, tare da faɗuwar gaba na bypass diode, kafin bypass diode ya kunna.
Amfanin BC modules shine, kafin bypass diode na waje ya kunna, tsarin haɗin PN na baya na BC cell kanta ya riga ya ba da wasu ikon juyar da baya. Wannan yana kama da Zener diode da aka gina a cikin cell.
A karkashin juzu'i na baya, mahaɗar PN na baya na BC cell na iya samar da rarraba reverse conduction a ƙaramin ƙarfin lantarki, yana iyakance ƙarin tashin ƙarfin reverse. Don haka a ƙarƙashin inuwa ɓangare, lokacin da waje bypass diode bai kunna ba tukuna, BC module na iya ci gaba da riƙe babban ƙarfin fitarwa.
Hoto 2 IV curve na module tare da cell ɗaya a inuwa.
Source: E. Özkalay, F. Valoti, M. Caccivio, A. Virtuani, G. Friesen, and C. Ballif, "The effect of partial shading on the reliability of photovoltaic modules in the built-environment," EPJ Photovoltaics, vol. 15, p. 7, Jan. 2024, doi: 10.1051/epjpv/2024001. Available: https://doi.org/10.1051/epjpv/2024001
Kyakkyawan Haƙuri Ba Ya Nufin Kariya Daga Inuwa
Kyakkyawan haƙuri na inuwa ba ya nufin BC cells ba su da tasiri daga inuwa
Akwai wani kuskure gama gari da ake buƙatar sharewa.
Kyakkyawan haƙuri na inuwa ba ya nufin BC cell ba ya shafar inuwa.
Kowane PV cell yana samar da ƙarancin ƙarfi da zarar an yi masa inuwa.
Idan yankin da aka yi inuwa a cikin ƙaramin zaren ya yi girma da yawa, ko kuma sel da yawa sun cika inuwa, to jimlar wutar lantarki ta baya na sel ɗin da aka yi inuwa na iya ƙetare jimlar wutar lantarki ta gaba na sauran sel ɗin da ba a yi inuwa ba. A wannan lokacin, diode na waje yana kunna.
Da zarar diode na waje ya kunna, wutar lantarki tana zagaya dukan ƙaramin zaren. Sel ɗin da ba a yi inuwa ba a cikin wannan ƙaramin zaren suma ana zagaye su, kuma gudummawarsu ga fitarwa tana raguwa sosai. Don haka idan yankin da aka yi inuwa ya yi girma, fa'idar samar da wutar lantarki na BC module shima yana raguwa.
Yanayin da BC modules suke haskakawa yawanci sune:
Seli ɗaya ko ƴan sel suna samun inuwa kaɗan;
Yankin da aka yi inuwa a cikin kowane ƙaramin zaren ya kasance ƙarami;
Inuwa tana diagonal, mai siffar tsiri, ko kuma warwatse a gida;
Diode na waje bai kunna gaba ɗaya ba tukuna.
Misali, inuwa diagonal daga sandar wutar lantarki na iya barin kowane ƙaramin zaren da ƙaramin yanki na inuwa. A wannan yanayin, BC module yakan nuna mafi kyawun juriyar inuwa.
Dalilin da yasa BC Modules ke Gudanar da Wurare Masu Zafi Mai Sauƙi
Me yasa BC modules suke da ƙananan zafin wurare masu zafi?
Akwai manyan dalilai guda biyu da BC modules ke yin sanyi hot spots.
Na farko, reverse current ya fi yaduwa
Ga sel na yau da kullun, rarraba reverse current sau da yawa ba daidai ba ne. Reverse breakdown na iya faruwa da farko a wasu wurare masu rauni na gida, kamar:
Wuraren lahani na gida;
Gefen sel;
Abubuwan da ba daidai ba na metallization;
Microcracks ko wuraren da suka gurbata;
Yankunan da ke da raunin passivation na gida.
Waɗannan wuraren suna aiki kamar maki masu rauni.
Da zarar reverse current ya tattara a waɗannan maki masu rauni, ƙarfin wutar lantarki na gida ya yi yawa sosai, zafin jiki ya tashi da sauri, kuma hot spot bayyananne ya samu.
Kamar yin amfani da adadin zafi ɗaya akan abubuwa biyu:
Farantin ƙarfe gaba ɗaya;
Wani tabo mai girman fil. Na ƙarshe yana yin zafi da sauri tabbas.
Na ƙarshe yana yin zafi da sauri tabbas.
Don haka haɗarin ga sel na yau da kullun a ƙarƙashin inuwa ba "zafi daidai a duk faɗin sel" ba ne, amma zafi mai ƙarfi na gida.
Tantanin BC yana da haɗin gwiwar PN da yawa a bayansa. Gudun juyawa na iya yaduwa cikin sauƙi a wurare da yawa maimakon taƙaita a ƴan wuraren lahani.
Don haka wutar juyawa a cikin tantanin BC tana rarrabuwa daidai, ƙarfin wutar gida ya rage, kuma zafin wurin zafi ya rage.
Na biyu, ƙarfin wutar juyawa yana ƙasa
Daga tsarin ƙarfin wutar zafi:
Photspot ≈ ∣Vrev∣ × Imismatch
a daidai wutar rashin daidaituwa, ƙaramin wutar juyawa yana nufin ƙarancin wutar lantarki.
Shi ya sa ƙaramin wutar juyawa zai iya zama hanyar kariya a yanayin inuwa.
Ga misali mai sauƙi.
Ka ce wutar layin ta kai 10A kuma tantanin daya ya sami inuwa mai yawa.
Idan tantanin al'ada ya kai wutar juyawa 15V bayan inuwa, ƙarfin da yake watsawa yana kusan:
P = 15V × 10A = 150W
Idan tantanin BC ya daure saboda tsarin bayansa kuma wutar juyawa ta iyakance zuwa kusan 6V, ƙarfin da yake watsawa yana kusan:
P = 6V × 10A = 60W
Bambancin a bayyane yake.
Matsayin zafin wuri mai zafi na gaske ya dogara da yankin da aka inuwa, zafin yanayi, saurin iska, rufin module, girman gilashi, ƙirar tantanin halitta, da hanyar gwaji, don haka ba za ku iya tantance shi da lamba ɗaya tsayayye ba.
Amma a wasu gwaje-gwaje na gaske da gogewar filin, modules na BC yawanci suna gudanar da zafin wuri mai zafi ƙasa da na al'ada. Misali, wasu modules na BC na iya kiyaye zafin wuri mai zafi ƙasa da kimanin 120 °C, yayin da sauran nau'ikan module na iya kaiwa 160 °C ko ma fiye.
Wasu tantanin halitta na BC da aka ƙera musamman suna samun wani abu kamar 'bypass diode a cikin tantanin halitta.' Wannan na iya saukar da zafin wuri mai zafi zuwa kimanin 90 °C yayin da module na tunani yake kusa da 190 °C, yana nuna cewa wannan nau'in ƙirar rarraba reverse conduction na iya rage zafin wuri mai zafi sosai.
Shin Ƙananan Reverse Breakdown Voltage Koyaushe Ya Fi Kyau?
Shin ƙananan reverse breakdown voltage koyaushe ya fi kyau?
Ba lallai ba ne.
Ƙananan reverse breakdown voltage yana taimakawa rage zafin wuri mai zafi yayin inuwa, amma kuma yana iya kawo musayar ƙira.
Idan hanyar reverse conduction ba ta da kyau, na iya ƙara yawan leakage da rage shunt resistance, wanda ke cutar da aikin samar da wutar lantarki na al'ada na tantanin halitta.
Don haka tantanin BC mai inganci yawanci yana buƙatar daidaita manufofi biyu:
A lokacin aiki na yau da kullun, kiyaye inganci mai girma, ƙarancin zubewa, da juriya mai girma;
Ƙarƙashin inuwa mai juyawa, samar da amintaccen gudanarwa mai juyawa a ƙarƙashin ƙananan wutar lantarki.
Wannan kuma shine dalilin da yasa juriyar inuwa ta bambanta tsakanin tantanin BC daban-daban.
Wasu tantanin BC suna karkata zuwa inganci kuma suna iya gina keɓewa mai ƙarfi, don haka wutar lantarki ta karye ta tashi. Wasu suna karkata zuwa juriyar inuwa kuma suna iya tsara ƙananan hanyoyin karye masu daidaituwa.
Don haka ba za ku iya cewa kawai "dukkan tantanin BC suna da juriyar inuwa iri ɗaya ba." Hanyar da ta fi dacewa ita ce:
tantanin BC da aka tsara da kyau zai iya amfani da tsarin haɗin PN na baya don samun ƙananan karye mai daidaituwa, kuma hakan yana inganta juriyar inuwa da tabo mai zafi.
Abubuwan Amfanin Tantanin BC A Taƙaice
Abubuwan amfanin tantanin BC a taƙaice
A dunkule, abubuwan amfanin tantanin BC a ƙarƙashin inuwa sun haɗa da:
Ƙananan asarar samar da wutar lantarki a ƙarƙashin ƙaramin inuwa, kafin diode na waje ya kunna;
Ƙananan ƙarfin wutar lantarki na gida;
Ƙananan zafin wuri mai zafi;
Mafi girman iyakar aminci na module.
Abin da Wannan ke Nufi ga Aikace-aikacen Module
Menene wannan ke nufi ga aikace-aikacen module?
A amfani na gaske, inuwa sau da yawa ba za a iya guje wa gaba ɗaya ba.
Musamman a yanayin rarraba, kamar:
Rufin gidaje;
Rufin kasuwanci da masana'antu;
Balcony PV;
BIPV;
Hawan da yawa;
Wuraren da gine-gine masu rikitarwa suka kewaye.
A cikin waɗannan aikace-aikace, modules na iya fuskantar inuwa na gida akai-akai.
Idan tantanin halitta yana da juriya mafi kyau ga inuwa da ƙananan zafin wuri mai zafi, yana nufin:
Mafi kyawun amincin module: ƙananan zafin wuri mai zafi yana rage tsufa na rufewa, lalacewar bayan fage, damuwa na gilashin gida, da haɗarin lantarki.
Ingantacciyar dogaro na dogon lokaci: zafin jiki mai girma a cikin gida yana hanzarta tsufa na kayan. Mafi raunin wurin zafi, mafi kwanciyar hankali na tsarin a kan lokaci.
Mafi yawan sarrafa asarar samarwa: idan inuwa ta gida ba ta da makawa, tsarin BC na iya rage wani ɓangare na asarar wutar lantarki.
Tsarin da ya fi dacewa.
Tsarin BC sun fi dacewa da rufin hadaddun, wuraren hawa da aka rarraba, da yanayin inuwa da yawa.
Takaitawa
Takaitawa
Kwayoyin BC suna da kyakkyawan juriyar inuwa da ƙananan zafin wurin zafi, ba saboda 'ba su shafar inuwa' ba, amma saboda suna da fa'idodi a tsari da halayen juyawa mara kyau.
A ƙarƙashin inuwa, kwayoyin yau da kullun na iya ganin rabuwar juyawa ta tattara a wuraren lahani na gida, yana haifar da babban ƙarfin wutar lantarki na gida da babban zafin wurin zafi.
Tsarin haɗin PN na baya na kwayar BC yana aiki kamar matsewar juyawa da aka rarraba. A ƙarƙashin inuwa, yana iya samar da juyawa a ƙananan ƙarfin juyawa kuma ya baza wutar juyawa daidai, wanda ke rage ƙarfin wurin zafi da zafin wurin zafi.
Amma ka tuna, ƙwayoyin BC ba su da cikakkiyar kariya daga inuwa. Lokacin da wurin da aka yi inuwa ya yi girma da yawa, ƙwayoyi da yawa suna cikin inuwa gabaɗaya, kuma ƙarfin substring ɗin ya yi ƙasa da isasshen ƙarfi, har yanzu bypass diode na waje yana kunna. A wannan lokacin, fitowar substring ɗin da aka yi bypass ɗin ta ragu sosai.
Don haka hanya mafi inganci don faɗi shi:
fa'idar ƙwayar BC ba ita ce kawar da tasirin inuwa ba, amma don sanya wannan tasirin ya zama mai iya sarrafawa. A ƙarƙashin inuwa ƙarami, yana rage asarar wutar lantarki; a ƙarƙashin inuwa mai nauyi, yana rage haɗarin wuri mai zafi.
Wannan shine ainihin dalilin da ya sa ƙwayoyin BC ke da fa'ida a wuraren inuwa masu rikitarwa.
Ra'ayin Ooitech
Abin sha'awa a nan shi ne cewa juriyar inuwa ba kawai zaɓin ƙirar ƙwaya ba ne, har ma ya dogara da yadda wannan tsarin interdigitated back pattern ɗin ake sake yin shi a kowace ƙwaya a cikin layi. Ƙananan canje-canje a cikin metallization, girman tazara, ko ingancin passivation na iya canza halayen rushewar baya da muka bayyana, wanda shine dalilin da ya sa sarrafa tsari a kan layin samar da BC module yake da mahimmanci kamar girke-girken ƙwaya. Ooitech ta shafe shekaru tana gina layukan samar da module turnkey don TOPCon, HPBC, ABC da sauran nau'ikan module na BC, don haka muna kallon waɗannan tagogin tsarin back-contact a hankali. Idan kana son ganin yadda waɗannan module ɗin ake ginawa a filin masana'anta, tashar mu ta YouTube a www.youtube.com/ooitech yana da hotunan layin samarwa na gaske da yawa da ya kamata a duba.
