Iiseli zelanga zisebenza njani

Iiseli zelanga ukufunxa ukukhanya kwelanga ukuvelisa imisebenzi yeebhetri eziqhelekileyo. Kodwa ngokungafaniyo neebhetri zemveli, i-voltage ephumayo kunye namandla aphezulu okukhutshwa kweebhetri zemveli zilungisiwe, ngelixa i-voltage ephumayo, yangoku, kunye namandla eeseli zelanga zihambelana neemeko zokukhanyisa kunye neendawo zokusebenza zokulayisha. Ngenxa yoko, ukusebenzisa iiseli zelanga ukuvelisa umbane, kufuneka uqonde ubudlelwane bangoku-voltage kunye nomgaqo wokusebenza weeseli zelanga.

Ukukhanya okucacileyo kwelanga:

Umthombo wamandla weeseli zelanga kukukhanya kwelanga, ngoko ke ubunzulu kunye nobuninzi besiganeko sokukhanya kwelanga bumisela imveliso yangoku kunye nombane welanga. Siyazi ukuba xa into ibekwe phantsi kwelanga, ifumana ukukhanya kwelanga ngeendlela ezimbini, enye ibe kukukhanya kwelanga, ize enye ibe kukukhanya kwelanga okusasazeka emva kokuba isasazwe zezinye izinto phezu komhlaba. Kwiimeko eziqhelekileyo, ukukhanya kwesiganeko esithe ngqo kubala malunga ne-80% yokukhanya okufunyenwe yiseli yelanga. Ngoko ke, ingxubusho yethu elandelayo kwakhona iya kugxininisa ekukhanyeni ngokuthe ngqo elangeni.

Ubukhulu kunye ne-spectrum yokukhanya kwelanga kunokubonakaliswa yi-spectrum irradiance, engamandla okukhanya kwiyunithi ye-wavelength ngeyunithi yendawo nganye (W/㎡um). Ubukhulu bokukhanya kwelanga (W/㎡) sisimbuku sabo bonke ubude bamaza okukhanya kwespectrum. Ukukhanya kokukhanya kwelanga kunxulumene nendawo elinganisiweyo kunye ne-engile yelanga xa ithelekiswa nomphezulu womhlaba. Oku kubangelwa kukuba ukukhanya kwelanga kuya kutsalwa kuze kusasazwe ngumoya ojikeleze umhlaba ngaphambi kokuba kufikelele emhlabeni. Imiba emibini yesikhundla kunye ne-angle ngokuqhelekileyo imelwe yinto ebizwa ngokuba yi-air mass (AM). Ukukhanya kwelanga, i-AMO ibhekisela kwimeko engaphandle kwendawo xa ilanga likhanya ngokuthe ngqo. Ukukhanya kwayo kumalunga ne-1353 W/㎡, ephantse ilingane nomthombo wokukhanya oveliswe yiradiation emnyama enobushushu obuyi-5800K. I-AMI ibhekisela kwimeko yomhlaba, xa ilanga likhanya ngokuthe ngqo, ukukhanya kokukhanya malunga ne-925 W / m2. I-AMI.5 ibhekisela kwimeko yomhlaba, xa ilanga lenzeke kwi-angle yama-degrees angama-45, ukukhanya kokukhanya malunga ne-844 W / m2. I-AM 1.5 ngokuqhelekileyo isetyenziselwa ukumela ukukhanya okuphakathi kokukhanya kwelanga kumphezulu womhlaba. Imodeli yesekethe yeSolar:

Xa kungekho kukhanya, iseli yelanga iziphatha njenge-pn junction diode. Ubudlelwane bangoku-voltage ye-diode efanelekileyo inokubonakaliswa njenge

Apho ndimele khona umsinga, u-V umele amandla ombane, i-Is yi-saturation current, kunye ne-VT=KBT/q0, apho i-KB imele i-BoItzmann engaguqukiyo, u-q0 yiyunithi yentlawulo yombane, kunye no-T bubushushu. Kwiqondo lobushushu begumbi, VT=0.026v. Kufuneka kuqatshelwe ukuba isalathiso se-Pn diode yangoku ichazwa ukuba ihambe ukusuka kuhlobo lwe-P ukuya kuhlobo lwe-n kwisixhobo, kwaye ixabiso elilungileyo nelibi lombane lichazwa njengohlobo lwe-terminal enokwenzeka. thabatha u-n-uhlobo lwetheminali enokwenzeka. Ngoko ke, ukuba le nkcazo ilandelwa, xa iseli yelanga isebenza, ixabiso layo lombane lilungile, ixabiso layo langoku libi, kwaye ijika le-IV likwi-quadrant yesine. Abafundi kufuneka bakhunjuzwe apha ukuba into ebizwa ngokuba yi-diode efanelekileyo isekelwe kwiimeko ezininzi zomzimba, kwaye iidiode zokwenyani ziya kuba nezinto ezithile ezingekho mthethweni ezichaphazela ubudlelwane be-voltage yangoku yesixhobo, njengesizukulwana-recombination current, apha Siya. sixoxe kakhulu. Xa iseli yelanga ibonakaliswe ekukhanyeni, kuya kubakho i-photocurrent kwi-pn diode. Ngenxa yokuba umkhombandlela wombane owakhelwe-ngaphakathi we-pn junction usuka ku-n-uhlobo ukuya kuhlobo lwe-p, izibini ze-electron-hole eziveliswe kukufunxwa kweefotoni ziya kubaleka ukuya kwisiphelo sohlobo lwe-n, ngelixa imingxuma iya kubaleka ukuya kwi-p. -uhlobo ekupheleni. Ifotocurrent eyenziwe ngaba babini iya kuhamba ukusuka kuhlobo lwe-n ukuya kuhlobo lwe-p. Ngokuqhelekileyo, ulwalathiso lwangoku lwangoku lwe-diode luchazwa njengokuhamba ukusuka kuhlobo lwe-p ukuya kuhlobo lwe-n. Ngale ndlela, xa kuthelekiswa ne-diode efanelekileyo, i-photocurrent eyenziwa yiseli yelanga xa ikhanyisa i-current negative. Ubudlelwane bangoku be-voltage yeseli yelanga yeyona diode ifanelekileyo kunye ne-IL ye-photocurrent engalunganga, enobukhulu bayo:

Ngamanye amazwi, xa kungekho kukhanya, IL=0, iseli yelanga yidiode eqhelekileyo. Xa iseli yelanga i-short-circuited, oko kukuthi, V=0, i-short-circuit current yi-Isc=-IL. Oko kukuthi, xa iseli yelanga ifutshane-ijikelezwe, i-short-circuit current yi-photocurrent eyenziwa ngukukhanya kwesiganeko. Ukuba iseli yelanga yisekethe evulekileyo, oko kukuthi, ukuba i-I=0, i-voltage yayo evulekileyo yesekethe yile:

Umzobo 2. Isekethe elinganayo yeseli yelanga: (a) ngaphandle, (b) kunye nochungechunge kunye ne-shunt resistors. Kufuneka kugxininiswe apha ukuba i-voltage yesiphaluka evulekileyo kunye ne-short circuit current zimbini iiparameters ezibalulekileyo zeempawu zeeseli zelanga.

Ukukhutshwa kwamandla kwiseli yelanga yimveliso yangoku kunye nombane:

Ngokucacileyo, ukukhutshwa kwamandla ngeseli yelanga ayiloxabiso elimiselweyo. Ifikelela kwixabiso eliphezulu kwindawo ethile yokusebenza ye-voltage yangoku, kwaye ubuninzi bamandla aphumayo Pmax inokumiselwa dp/dv=0. Sinokufumanisa ukuba i-voltage ephumayo kumandla aphezulu wokukhupha i-Pmax yile:

kwaye imveliso yangoku ithi:

Awona mandla aphezulu emveliso yeseli yelanga ngala:

Ukusebenza kakuhle kweseli yelanga kubhekiselele kumlinganiselo weseli yelanga eguqula iPin yamandla yesibane sesiganeko kumandla ombane aphezulu, oko kukuthi:

Imilinganiselo ngokubanzi yeeseli zelanga isebenzisa umthombo wokukhanya ofana nokukhanya kwelanga ngepin=1000W/㎡.

Ngovavanyo, ubudlelwane be-voltage yangoku yeeseli zelanga ayilandeli ngokupheleleyo le nkcazo yethiyori engentla. Oku kungenxa yokuba ifowuni ye-photovoltaic ngokwayo inento ebizwa ngokuba yi-series resistance and resistance resistance. Kuyo nayiphi na impahla ye-semiconductor, okanye uqhagamshelwano phakathi kwe-semiconductor kunye nesinyithi, ngokuqinisekileyo kuya kubakho ukuchasana okukhulu okanye okuncinci, okuya kwenza ukuchasana kochungechunge lwesixhobo se-photovoltaic. Ngakolunye uhlangothi, nayiphi na indlela yangoku ngaphandle kwe-Pn diode efanelekileyo phakathi kwe-electrode efanelekileyo kunye ne-negative yesixhobo se-photovoltaic iya kubangela into ebizwa ngokuba yi-leakage current, njenge-generation-recombination current kwisixhobo. , umphezulu wokudibanisa umphezulu wangoku, ukwahlulwa komphetho okungaphelelanga kwesixhobo, kunye nentsimbi yokungena yokungena.

Ngokuqhelekileyo, sisebenzisa ukuxhathisa kwe-shunt ukuchaza ukuvuza kwangoku kweeseli zelanga, oko kukuthi, i-Rsh = V / Ileak. Okukhona kukhulu ukuchasana kwe-shunt kukuba, incinci ukuvuza kwangoku. Ukuba siqwalasela ukuchasana ngokudibeneyo kwe-Rs kunye nokumelana ne-shunt i-Rsh, ubudlelwane be-voltage yangoku yeseli yelanga inokubhalwa ngolu hlobo:

Sinokusebenzisa iparamitha enye kuphela, into ebizwa ngokuba yi-fiber factor, ukushwankathela zombini imiphumo yokuchasana kochungechunge kunye nokuxhatshazwa kwe-shunt. ichazwe njenge:

Kuyacaca ukuba into yokuzalisa iyona nto iphezulu ukuba akukho sixhasi sechungechunge kwaye ukuchasana kwe-shunt akunasiphelo (akukho kuvuza okwangoku). Nakuphi na ukwanda kokumelana nochungechunge okanye ukuncipha kokuchasana kwe-shunt kuya kunciphisa into yokuzalisa. Ngele ndlela,. Ukusebenza kweeseli zelanga kunokubonakaliswa ngeeparamitha ezintathu ezibalulekileyo: i-voltage yesiphaluka evulekileyo iVoc, i-short circuit yangoku i-Isc, kunye nokuzalisa i-FF.

Ngokucacileyo, ukuphucula ukusebenza kakuhle kweseli yelanga, kuyimfuneko ukuba kwangaxeshanye ukwandise umbane wayo ovulekileyo wesiphaluka, i-short circuit current (oko kukuthi, i-photocurrent), kunye nokuzalisa into (oko kukuthi, ukunciphisa ukuxhathisa uchungechunge kunye nokuvuza kwangoku).

I-voltage yesiphaluka evulekileyo kunye nombane wesiphaluka esifutshane: Ukuqwalasela kwifomula yangaphambili, i-voltage yesiphaluka evulekileyo yeseli yelanga inqunywe yi-photocurrent kunye neseli egcweleyo. Ngokwembono ye-semiconductor physics, umbane ovulekileyo wesekethe ulingana nomahluko wamandla weFermi phakathi kwee-electron kunye nemingxuma kwindawo yentlawulo yesithuba. Ngokubhekiselele kwi-saturation yangoku ye-Pn diode efanelekileyo, ungasebenzisa:

ukuvakalisa. apho i-q0 imele intlawulo yeyunithi, i-ni imele i-intrinsic carrier concentration ye-semiconductor, i-ND kunye ne-NA nganye imele ukuxinwa komnikeli kunye nomamkeli, i-Dn kunye ne-Dp nganye imele i-coefficient yokusasazwa kwee-electron kunye nemingxuma, le ntetho ingentla ithatha ukuba n. - Imeko apho zombini ummandla wodidi kunye nommandla wohlobo lwe-p zombini zibanzi. Ngokuqhelekileyo, kwiiseli zelanga ezisebenzisa i-p-type substrates, indawo yohlobo lwe-n ayinzulu kakhulu, kwaye le ntetho ingentla ifuna ukuguqulwa.

Sichazile ngaphambili ukuba xa i-solar cell ikhanyisa, i-photocurrent yenziwe, kwaye i-photocurrent yi-current-circuit current in the current-voltage relationship of the solar cell. Apha siza kuchaza ngokufutshane imvelaphi yefotocurrent. Umlinganiselo wokuvelisa abathwali kwiyunithi yeyunithi ngexesha leyunithi (iyunithi m -3 s -1 ) igqitywe ngumlinganiso wokukhanya wokukhanya, oko kukuthi.

Phakathi kwazo, i-α imele i-coefficient yokufunxa ukukhanya, okuyiyo ukuqina kweefotoni zesiganeko (okanye i-photon flux density), kwaye i-R ibhekisela kwi-coefficient ye-reflection, ngoko imele ubunzulu beefotoni zesiganeko ezingabonakali. Ezona ndlela zintathu ziphambili ezenza i-photocurrent zezi: ukusasazwa kwangoku kwee-elektroni ezithwala i-elektroni kwingingqi yohlobo lwe-p, usasazo lwangoku lwemingxuma ephetheyo encinci kummandla wohlobo lwe-n, kunye nokukhukuliseka kwee-electron kunye nemingxuma kwindawo yentlawulo yesithuba. yangoku. Ke ngoko, ifotocurrent inokubonakala ngathi:

Phakathi kwazo, i-Ln kunye ne-Lp nganye imele ubude bokusasazwa kwee-electron kwingingqi yohlobo lwe-p kunye nemingxuma kwingingqi ye-n-type, kwaye ububanzi bendawo yentlawulo yendawo. Ukushwankathela ezi ziphumo, sifumana intetho elula yombane wesekethe evulekileyo:

apho iVrcc imele ireyithi yokudityaniswa kwakhona kweeperi ze-electron-hole kwiyunithi nganye. Ewe, esi sisiphumo sendalo, kuba amandla ombane wesekethe evulekileyo alingana nokwahlukana kwamandla e-Fermi phakathi kwee-electron kunye nemingxuma kwindawo yentlawulo yesithuba, kwaye umahluko wamandla weFermi phakathi kwee-electron kunye nemingxunya umiselwa yizinga lokuvelisa umthwali kunye nesantya sokudibanisa kwakhona. .