Hanyar lissafin halin yanzu mai juyi

Da farko lissafta jimlar ikon P na duk kayan aikin lantarki, a cikin lissafin jimlar yanzu A lamba I = P/U,yatsan yatsaya kamata ya zama mafi girma fiye da jimlar halin yanzu, dole ne a sami wani tazara, ko a cikin shigar da wasu na'urorin lantarki ba za su iya jurewa ba.Ragowar yabo na gida na 30MA na iya.Canjin yatsan yatsaGabaɗaya ba aikin kariya ya yi oba ba, idan kuna son kare layin zuwa ƙaramin magudanar da'ira, ƙaramin mai jujjuyawar ba zai iya zaɓar babba da yawa ba.Gabaɗaya, ana amfani da nau'in C.

Ƙananan na'urorin haɗiyi amfani da hanyar lissafi mai sauƙi wanda ke da wasu kurakurai waɗanda ba su da girma sosai kuma ana iya yarda da su a aikin injiniya:

(1) don 10/0.4kV ƙarfin lantarki sa naƙananan na'ura mai ba da hanya tsakanin hanyoyin sadarwa, na iya yin la'akari da babban ƙarfin ƙarfin lantarki na ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan ƙananan 200 ~ 400MVA ko ma mafi girma, don haka bisa ga rashin iyaka don la'akari, kuskuren ya kasance ƙasa da 10%).

(2) Gb50054-95 "Lambar Rarraba Rarraba Ƙarfin Ƙarfin Wuta" 2.1.2 tanade-tanade: "Lokacin da jimillar ƙididdigewa na yanzu na motar da aka haɗa kusa da gajeren kewayawa ya wuce 1% na gajeren kewayawa, tasirin na halin yanzu ya kamata a haɗa da ra'ayoyin motar.Idan ɗan gajeren lokaci na yanzu shine 30KA, ɗauki 1% na shi, wanda yakamata ya zama 300A.Jimlar ƙarfin motar yana da kusan 150KW, kuma lokacin da aka fara shi a lokaci guda, amsawar da aka haɗa a halin yanzu yakamata ya zama 6.5∑ In.

(3) Wutar lantarki mai ƙarfi ta UK na mini-circuit breaker tana wakiltar gajeriyar kewayawa ta gefe (circuit), lokacin da gefen ya kai matsayin da aka ƙididdige shi, ainihin ƙarfin gefen gefen shine ƙimar maki ɗari na ƙimar ƙarfinsa.Saboda haka, lokacin da firamare irin ƙarfin lantarki ne da aka ƙididdige ƙarfin lantarki, na biyun shine abin da ake sa ransa na ɗan gajeren lokaci.

(4) Ƙananan gefen mai watsewar da'ira wanda aka ƙididdige halin yanzu It=Ste/1.732U Ste ita ce ƙarfin ƙaramar mai watsewa (KVA), Ue shine ƙaramin ƙarfin da aka ƙididdige shi (voltage mara nauyi), Ue= 0.4kV lokacin 10 / 0.4kV, saboda haka, gefen sakandaren da aka ƙididdige halin yanzu na ƙaramin keɓaɓɓiyar mai katsewa ya kamata a ƙididdige shi kawai azaman ƙarfin ƙaramin keɓaɓɓiyar keɓaɓɓiyar X1.44 ~ 1.50.

(5) Bisa ga ma'anar Uk a cikin (3), gajeriyar kewayawa na gefen taimako (gajerun kewayawa na lokaci uku) shine ma'anar I(3) don Uk, da kuma gajeriyar kewayawa na yanzu. Gefen taimako ( gajeriyar kewayawa na mataki uku) shine I(3) =Ite/Uk, wanda shine ingantaccen darajar AC.

(6) Karkashin hakamini-circuit breakeriya aiki, idan akwai gajeriyar kewayawa tsakanin matakan biyu, to I (2) = 1.732I(3)/2=0.866I(3)

Ƙididdigar da ke sama ita ce ƙimar gajeren da'irar a halin yanzu a madaidaicin ma'ajin da'ira, wanda shine mafi girman haɗari ga gajeriyar da'ira.Idan akwai tazarar tazara tsakanin madaidaicin wurin kewayawa da ƙaramin kewayawa, la'akari da impedance na layin.