Reactance - ndichiyani?

Munthu akhala akugwiritsa ntchito zosowa zawo magetsi, mankhwala, ndi mphamvu nyukiliya. Kuti timve bwino lomwe luso aliyense wa iwo pali m'ndandanda wa malingaliro kulola kuti mufotokozere zomwenso awo. Mwachitsanzo, zimaonetsa monga mphamvu, mwamphamvu, kachulukidwe, neri Al., Ankagwiritsa ntchito maphunziro osati magetsi, koma njira zina zodziwika mphamvu. Mmodzi mwa anthu amenewo mfundo chilengedwe chimagwiritsidwa ntchito, mawu akuti "kukana" magetsi. M'madera ena, pali analogues - mayamwidwe, kubalalika, kusinkhasinkha, etc. "Fundo" - Ndipotu, ndi khalidwe la zomvetsa munda mphamvu. Cholinga cha sayansi kwagona kudziwa zimene chifukwa cha kukana lapansi.

Fundo mu dera ali ndi chikhalidwe wapawiri - nenani, kukana ndi reactance. Pakuti kukana magetsi ya kondakitala ndi khalidwe lalikulu ndi kukana chifukwa cha kayendedwe ka onyamula wochititsa zakuthupi. Chifukwa potsimikizira zimenezi zingakhale zosiyanasiyana anafotokoza dzina osiyana. Kukana nthawi zonse limodzi ndi kusintha mtundu wina wa mphamvu kwa wina ndi kuchepetsa limatiphunzitsa mphamvu. Pakuti nkhani ya magetsi njira yobweretsa mphamvu, izi kusintha mphamvu kutembenuka mu matenthedwe electromotive mphamvu, maginito kapena mphamvu ya magetsi.

Mbiri yakale, woyamba kukana yonena anali kuphunzira kukana, ndilo chifukwa kutembenuka kwa wochititsa gwero kwa magetsi mphamvu. Izi zimachitika chifukwa chakuti milandu (ma elekitironi ndi) muulamuliro wa kumunda EMF gwero anasamukira pa guidewire mophiphiritsa, "akukankha" makhiristo kapena mamolekyulu pa nkhaniyi. Choncho, kuwombola tonse kutengerapo mphamvu kumabweretsa kuwonjezeka mu kutentha kwa wochititsa, ndi i.e. pali kutembenuka kwa ife mphamvu ngati zamagetsi ku mphamvu matenthedwe. Ngati gwero la mphamvu electromotive sasintha malangizo ake ndi kufunika kwa U, ine ziliri pa dera lotchedwa zonse, ndi kukana R a dera lino masamu malamulo Ohm akuti: R = U / I.

Fundo DC dera zitha kukhala yogwira. Reactance "zimapangitsa lokha anamva" mwa madera AC, amene ali kwenikweni inductance (koyilo) kapena capacitance (capacitor). Kwenikweni, wochititsa aliyense ali inductance ndi capacitance, koma kawirikawiri ali ndi negligible kuti ponyalanyaza. The inductance ndi capacitance pamene ukuyenda adalira milandu magetsi atatembenuzidwa mphamvu zawo ndi maginito ya koyilo kapena munda magetsi a dielectric lapansi. The kusungidwa mphamvu Choncho, pa kusintha chizindikiro cha gwero la emf, ndi anabwerera mu mawonekedwe a milandu mphamvu kayendedwe, choncho dzina - "reactance".

Inductance mu AC dera "chimatsutsana" otaya panopa mwa chodabwitsa kudziletsa kupatsidwa ulemu: kusintha panopa kwaiye kusintha gwero emf zimayambitsa kusintha m'munda mu atomu kuti amayesetsa kukhala pano mu dera chifukwa cha mphamvu kusungidwa za kuthengo maginito. Kuyeza mphamvu kusungidwa ndi muyeso wa dera inductance L, potsata pafupipafupi f AC. The reactance wa inductor ndi anatsimikiza ndi chilinganizo zotsatirazi:

XL = 2 * π * f * L.

A capacitor mu AC dera amasonkhana ndi mphamvu ya m'munda magetsi ndi dielectric mlandu. Pamene kusintha ukulu ndi / kapena malangizo a gwero la emf voteji kudutsa mbale capacitor mothandizidwa ndi mantha kugwa, mmene yaitali, zazikulu capacitance C wa capacitor lapansi.

The zotakasika impedance wa capacitor a, komanso pafupipafupi yozungulira, kwapatsidwa mwa:

Xc = 1 / (2 * π * f C *).

Kuyambira mawu amenewa amafotokoza momveka bwino kuti kuwonjezeka mu pafupipafupi ndiponso / kapena capacitance impedance amachepetsa. Motero, kwa AC dera, kumene pali resistor, ndi inductor ndi capacitor, m'pofunika kuthandauza ena okwana kukana ndi reactance. Ambiri, tikutsata ndondomeko za kuwerengetsa ndi impedance ali "pifagorovsky amakambirana":

Zv2 = Rv2 + (XL + Xc) V2

* Chidziwitso: Mu «ndime» ayenera kuwerenga «Z lofanana mbali zonse", etc.

Ndipo potsiriza impedance ndiyo njira motere:

Z = √ (squarte) Rv2 + (XL + Xc) V2.