Inverters yog ib pawg loj ntawm cov hloov pauv zoo li qub, uas suav nrog ntau yam niaj hnub no's khoom siv tau“hloov”hluav taws xob tsis nyob rau hauv cov tswv yim, xws li voltage thiab zaus, thiaj li yuav tsim tau ib qho kev tso zis uas yog sib xws nrog cov kev cai ntawm lub load.

Feem ntau hais lus, inverters yog cov cuab yeej uas muaj peev xwm hloov cov tam sim no ncaj qha mus rau hauv kev hloov tam sim no thiab muaj ntau heev hauv kev lag luam automation kev siv thiab hluav taws xob tsav.Cov qauv tsim thiab kev tsim ntawm ntau hom inverter hloov raws li txhua daim ntawv thov tshwj xeeb, txawm tias cov tub ntxhais ntawm lawv lub hom phiaj tseem ceeb yog tib yam (DC rau AC hloov dua siab tshiab).

1.Standalone thiab Grid-Connected Inverters

Inverters siv nyob rau hauv daim ntawv thov photovoltaic yog keeb kwm muab faib ua ob pawg loj:

:Standalone inverter

:Daim phiaj-txuas inverter

Standalone inverters yog rau cov ntawv thov uas cov nroj tsuag PV tsis txuas nrog lub zog loj hauv lub network.Lub inverter muaj peev xwm muab hluav taws xob hluav taws xob rau cov khoom sib txuas, ua kom muaj kev ruaj ntseg ntawm cov hluav taws xob tseem ceeb (voltage thiab zaus).Qhov no ua rau lawv nyob rau hauv cov kev txwv ua ntej, muaj peev xwm tiv taus cov xwm txheej overloading ib ntus.Hauv qhov xwm txheej no, lub inverter yog txuas nrog lub roj teeb cia hauv thiaj li yuav ua kom lub zog sib xws.

Grid-connected inverters, ntawm qhov tod tes, muaj peev xwm synchronize nrog cov kab hluav taws xob uas lawv txuas nrog vim, qhov no, qhov voltage thiab zaus yog.“yuam”los ntawm daim phiaj loj.Cov inverters no yuav tsum tuaj yeem txiav tawm yog tias daim phiaj tseem ceeb tsis ua haujlwm txhawm rau kom tsis txhob muaj qhov cuam tshuam rov qab ntawm daim phiaj loj, uas tuaj yeem sawv cev rau qhov txaus ntshai heev.

Daim duab 1 - Piv txwv ntawm Standalone system thiab Grid-connected system.Duab los ntawm Biblus.

2.Lub luag haujlwm ntawm Bus Capacitor yog dab tsi

Lub hom phiaj ntawm lub inverter yog los hloov lub DC waveform voltage rau hauv AC teeb liab thiaj li yuav hno lub hwj chim rau hauv ib qho load (xws li daim phiaj fais fab) ntawm ib zaus thiab nrog lub kaum sab xis me me (φ ≈0).Ib qho yooj yim Circuit Court rau ib theem unipolar Pulse-Width Modulation (PWM) yog qhia hauv daim duab2 ( tib lub tswv yim dav dav tuaj yeem txuas ntxiv mus rau peb theem system).Nyob rau hauv no schematic, ib tug PV system, ua raws li ib tug DC voltage qhov chaw nrog ib co qhov chaw inductance, yog zoo li tus AC teeb liab los ntawm plaub IGBT keyboards nyob rau hauv parallel nrog freewheeling diodes.Cov keyboards no tau tswj hwm ntawm lub rooj vag los ntawm PWM teeb liab, uas feem ntau yog cov zis ntawm IC uas piv cov neeg nqa khoom nthwv dej (feem ntau yog sine nthwv dej ntawm qhov xav tau ntau zaus) thiab siv nthwv dej ntawm ntau zaus (feem ntau yog daim duab peb sab yoj. ntawm 5-20kHz).Cov zis ntawm IGBTs yog zoo li tus AC teeb liab haum rau siv los yog daim phiaj txhaj tshuaj los ntawm daim ntawv thov ntawm ntau yam topologies ntawm LC lim.

Tau Txais Quote

Daim duab 2: Pulsed Width Modulation (PWM) ib-theemkev teeb tsa inverter.Lub IGBT keyboards, nrog rau LC tso zis lim, teeb lub DC input teeb liab rau hauv lub teeb liab AC usable.Qhov no induces adeleterious voltage ripple hla PV terminals.Lub tsheb npavcapacitor yog qhov loj me txhawm rau txo qhov ripple no.

Kev ua haujlwm ntawm IGBTs qhia txog qhov hluav taws xob ripple mus rau lub davhlau ya nyob twg ntawm PV array.Qhov no ripple yog deleterious rau lub lag luam ntawm PV system, txij li thaum lub nominal voltage thov mus rau lub terminals yuav tsum tau tuav nyob rau hauv lub max zog point (MPP) ntawm IV nkhaus thiaj li yuav rho tawm lub zog tshaj plaws.Ib qho hluav taws xob ripple ntawm PV terminals yuav oscillate lub zog rho tawm los ntawm lub cev, ua rau

qis nruab nrab fais fab tso zis (Daim duab 3).Ib lub capacitor ntxiv rau hauv lub tsheb npav txhawm rau txhawm rau tawm qhov hluav taws xob ripple.

Daim duab 3: Ib qho hluav taws xob ripple nkag mus rau PV terminals los ntawm PWM inverter scheme hloov qhov kev siv hluav taws xob tawm ntawm qhov hluav taws xob max (MPP) ntawm PV array.Qhov no qhia txog ripple nyob rau hauv lub hwj chim tso zis ntawm lub array thiaj li hais tias qhov nruab nrab tso zis hwj chim yog qis dua lub nominal MPP

Lub amplitude (ncaj mus rau lub ncov) ntawm lub voltage ripple yog txiav txim los ntawm lub switching zaus, PV voltage, tsheb npav capacitance, thiab lim inductance raws li:

qhov twg:

VPV yog lub hnub ci vaj huam sib luag DC voltage,

Cbus yog lub capacitance ntawm lub tsheb npav capacitor,

L yog inductance ntawm lim inductors,

fPWM yog qhov hloov pauv zaus.

Qhov sib npaug (1) siv rau qhov zoo tshaj plaws capacitor uas tiv thaiv cov nqi ntws los ntawm lub capacitor thaum lub sij hawm them nyiaj thiab tom qab ntawd tso tawm lub zog nyob rau hauv qhov hluav taws xob tsis muaj kev tiv thaiv.Nyob rau hauv kev muaj tiag, tsis muaj capacitor yog zoo tagnrho (Daim duab 4) tab sis yog tsim los ntawm ntau yam.Ntxiv nrog rau qhov zoo tshaj plaws capacitance, lub dielectric tsis zoo kawg nkaus tiv taus thiab me me ntws tam sim no ntws los ntawm lub anode mus rau cathode raws ib tug finite shunt resistance (Rsh), bypassing dielectric capacitance (C).Thaum tam sim no los ntawm lub capacitor ntws, cov pins, foils, thiab dielectric tsis ua haujlwm zoo thiab muaj qhov sib npaug sib npaug (ESR) nyob rau hauv series nrog lub capacitance.Thaum kawg, lub capacitor khaws qee lub zog hauv qhov chaw sib nqus, yog li muaj qhov sib npaug ntawm cov inductance (ESL) nyob rau hauv series nrog lub capacitance thiab ESR.

Daim duab 4: Sib npaug Circuit Court ntawm ib tug generic capacitor.Ib tug capacitor yogMuaj ntau lub ntsiab lus tsis zoo, suav nrog dielectric capacitance (C), qhov tsis muaj qhov kawg ntawm shunt tsis kam los ntawm dielectric uas hla lub capacitor, series resistance (ESR), thiab series inductance (ESL).

Txawm hais tias nyob rau hauv ib qho kev tivthaiv zoo li yooj yim li lub capacitor, muaj ntau lub ntsiab lus uas tuaj yeem ua tsis tiav lossis degrade.Txhua yam ntawm cov khoom no tuaj yeem cuam tshuam rau tus cwj pwm ntawm lub inverter, ob qho tib si ntawm AC thiab DC sab.Txhawm rau txiav txim siab qhov cuam tshuam ntawm qhov tsis zoo ntawm cov khoom siv capacitor muaj nyob rau ntawm qhov hluav taws xob ripple qhia thoob plaws PV terminals, PWM unipolar H-bridge inverter (Daim duab 2) tau simulated siv SPICE.Cov lim capacitors thiab inductors yog tuav ntawm 250µF thiab 20mH, raws li.Cov qauv SPICE rau IGBTs yog muab los ntawm kev ua haujlwm ntawm Petrie li al.Lub PWM teeb liab, uas tswj cov IGBT keyboards, txiav txim siab los ntawm kev sib piv thiab inverting kev sib piv Circuit Court rau siab thiab qis-sab IGBT keyboards, raws li.Cov tswv yim rau PWM tswj yog 9.5V, 60Hz sine carrier yoj thiab 10V, 10kHz triangular yoj.