Metering thiab kev tiv thaiv tam sim no transformers pab lub hom phiaj sib txawv hauv cov hluav taws xob hluav taws xob, thiab lawv cov qauv tsim muaj feem cuam tshuam txog qhov tseem ceeb sib txawv. Kev nkag siab txog qhov sib txawv ntawm ob hom CTs no yog qhov tseem ceeb rau cov kev qhia tshwj xeeb thiab kev tsim qauv, vim tias siv hom tsis ncaj ncees lawm hauv daim ntawv thov tuaj yeem ua rau kev ntsuas qhov yuam kev, tsis raug them nqi, lossis kev tiv thaiv tsis ua haujlwm.
Qhov tseem ceeb tshaj qhov sib txawv yog nyob rau hauv lawv cov hom phiaj kev ua tau zoo. Kev ntsuas CT yog tsim los muab qhov tseeb tshaj plaws ntawm cov kev khiav hauj lwm tam sim no, feem ntau yog li ntawm 5% txog 120% ntawm cov ntsuas thawj tam sim no. Nws lub hom phiaj yog txhawm rau txhawm rau ntsuas lub zog meej rau kev them nqi, kev saib xyuas kev noj, thiab kev ntsuas kev ua haujlwm. Ib qho kev tiv thaiv CT, los ntawm qhov sib txawv, yog tsim los tswj qhov tseeb thiab cov kab sib txuas ntawm cov tam sim no siab heev -feem ntau 10 mus rau 20 npaug ntawm qhov ntsuas tam sim no lossis ntau dua - kom tiv thaiv relays tuaj yeem ntseeg tau thiab teb rau cov xwm txheej tsis raug.
Qhov sib txawv ntawm lub hom phiaj no ua rau muaj qhov sib txawv ntawm qhov tseeb hauv chav kawm tshwj xeeb. Metering CTs tau teev nrog cov chav kawm raug xws li 0.2, 0.2S, 0.5, 0.5S, lossis 1, qhov twg tus lej sawv cev qhov feem pua siab tshaj plaws ntawm qhov ntsuas tam sim no. Cov ntawv thov nyiaj tau los feem ntau xav tau Chav Kawm 0.2 lossis 0.5, thaum cov ntawv thov saib xyuas qhov tseem ceeb tsawg dua tuaj yeem lees txais Chav Kawm 1. Kev Tiv Thaiv CTs tau teev tseg nrog cov chav kawm xws li 5P lossis 10P, qhov twg tus lej sawv cev qhov yuam kev ntau tshaj plaws ntawm qhov raug txwv qhov tseeb. Piv txwv li, A 5P20 CT, tswj 5% qhov tseeb txog 20 npaug ntawm qhov ntsuas thawj tam sim no.
Lwm qhov sib txawv tseem ceeb yog tus cwj pwm saturation. Metering CTs yog txhob txwm tsim los kom saturate ntawm tus nqi qis ntawm cov ntsuas tam sim no los tiv thaiv cov cuab yeej ntsuas kev sib txuas los ntawm kev puas tsuaj thaum ua txhaum. Qhov no yog tus cwj pwm los ntawm qhov muaj kev nyab xeeb (Fs), uas qhia txog ntau yam ntawm cov ntsuas tam sim no uas tau lees paub tias muaj kev nyab xeeb. Kev tiv thaiv CTs, ntawm qhov tod tes, yog tsim los ncua kev saturation ntev li ntev tau, kom ntseeg tau tias CT tuaj yeem ua ncaj ncees rov ua txhaum tam sim no rau kev tiv thaiv relay los soj ntsuam.
Lub hauv paus kev tsim kho kuj txawv. Metering CTs feem ntau muaj cov tub ntxhais me me nrog qhov qis qis qis qis kom ua tiav thaum ntxov saturation. Kev tiv thaiv CTs xav tau cov cores loj dua nrog cov saturation flux ceev dua kom tswj tau cov linearity ntawm cov dej ntws siab. Qhov no ua rau kev tiv thaiv CTs lub cev loj dua thiab kim dua li kev ntsuas CTs ntawm qhov sib npaug ntawm qhov kev ntsuas tam sim no.
Hauv kev xyaum, ntau qhov kev teeb tsa siv cais CTs rau kev ntsuas thiab kev tiv thaiv kev ua haujlwm. Ib chav kawm 0.2 metering CT tsis tuaj yeem ua haujlwm tiv thaiv CT vim tias nws yuav saturate sai dhau thaum ua txhaum, muaj peev xwm tiv thaiv kev tiv thaiv relay los ntawm kev ua haujlwm kom raug. Hloov pauv, 5P20 kev tiv thaiv CT yuav tsis muab qhov tseeb xav tau rau kev ntsuas nyiaj tau los. Rau cov ntawv thov uas yuav tsum muaj ob txoj haujlwm, dual -core CTs nrog cais ntsuas thiab tiv thaiv cores hauv ib lub tsev feem ntau yog siv.
Hauv cov ntsiab lus, qhov sib txawv ntawm qhov ntsuas thiab kev tiv thaiv CTs nyob rau hauv lawv qhov tseem ceeb ntawm kev tsim: metering CTs ua ntej qhov tseeb ntawm qhov tam sim no, thaum kev tiv thaiv CTs ua qhov tseem ceeb ntawm kev ua txhaum tam sim no. Xaiv hom raug rau txhua daim ntawv thov yog qhov tseem ceeb rau kev them nqi kom raug thiab kev tiv thaiv txhim khu kev qha.