Ficha técnica n.º 13

ESPAÇO DE FORMAÇÃO

Ficha técnica n.o 13 {±ƚĬŅ {åĜƻŅƋŅ TEYPS TIM\SXS%EXIG TX &8*( Ƴ &GEHIQME HI +SVQE±­S

11. ANÁLISE DE CIRCUITOS EM CORRENTE ALTERNADA (PARTE 2) 11.3.2. Circuito indutivo em corrente alternada 3SW GMVGYMXSW TYVEQIRXI MRHYXMZSW E STSWM±­S ª GMVGYPE±­S HE GSV VIRXI ³ JIMXE TIPE +SV±E *PIXVSQSXVM^ J I Q HI EYXSMRHY±­S HE FSFM RE I GLEQE WI VIEX¬RGME MRHYXMZE < 1 I I\TVMQI WI IQ Ǟ &REPMWERHS YQ GMVGYMXS GSQ YQE FSFMRE IQ GSVVIRXI GSRX¸RYE TS HIQSW ZIVMǻGEV S IJIMXS HE 1IM HI 1IR^ &WWMQ UYERHS S MRXIVVYTXSV ³ JIGLEHS GVMEV WI « YQE GSVVIRXI IP³XVMGE MRHY^MHE RS GMVGYMXS GYNS WIR XMHS WI STÀIQ ª GSVVIRXI TVMRGMTEP VIXEVHERHS EWWMQ S WIY MR¸GMS 5IPS GSRXV«VMS UYERHS WI EFVI S MRXIVVYTXSV XEQF³Q TIPE 1IM HI 1IR^ E GSVVIRXI R­S GIWWEV« HI MQIHMEXS TSMW WYVKMV« YQE GSVVIRXI MRHY^MHE UYI E VIXEVHEV« & +MKYVE VITVIWIRXE IWXI IJIMXS

&S ETPMGEVQSW YQE XIRW­S E YQE FSFMRE E GSVVIRXI R­S WYVKMV« MQI HMEXEQIRXI TSMW GSQS EREPMWEHS ERXIVMSVQIRXI WYVKMV« RS GMVGYMXS HIZMHS ª EYXSMRHY±­S YQE GSVVIRXI GSQ YQ WIRXMHS XEP UYI JE^ VIXEV HEV S ETEVIGMQIRXS HE GSVVIRXI TVMRGMTEP RS GMVGYMXS *WXE ETIREW ETE VIGIV« UYERHS E XIRW­S EXMRKMV S WIY ZEPSV Q«\MQS &MRHE HIZMHS ESW JIR¾QIRSW HI EYXSMRHY±­S E GSVVIRXI MV« EYQIRXEV IRUYERXS E XIRW­S HIGVIWGI I EXMRKI YQ Q«\MQS UYERHS E XIRW­S ETPMGEHE ³ RYPE 6YER HS E XIRW­S MRZIVXI S WIY WIRXMHS E GSVVIRXI GSQI±E E HMQMRYMV QEW IWXE HMQMRYM±­S ³ VIXEVHEHE I ERYPE WI UYERHS E XIRW­S EXMRKI S WIY Q«\MQS RIKEXMZS SY WINE YQ UYEVXS HI TIV¸SHS QEMW XEVHI & +MKYVE ETVIWIRXE S HIWJEWEQIRXS HE SRHE HE XIRW­S I HE GSV VIRXI RYQ GMVGYMXS TYVEQIRXI GETEGMXMZS SRHI TSHIVIQSW EREPMWEV UYI E GSVVIRXI IWX« EXVEWEHE } IQ VIPE±­S ª XIRW­S

u, i Umáx.

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Imáx.

t2

t1

uL

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ф= 90º uR t

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t3

t4

t Figura 78. Representação vetorial e cartesiana da tensão e respetiva corrente num circuito

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puramente indutivo.

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11.3.3. Circuito indutivo real – Circuito RL U

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L

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Figura 77. Circuito capacitivo alimentado por uma corrente alternada e as respetivas formas de onda da tensão e corrente.

*Q GSVVIRXI EPXIVREHE SW IJIMXSW HE EYXSMRHY±­S W­S GSRWXERXIW 5S HIQSW GSRGPYMV UYI UYERXS QEMSV JSV S GSIǻGMIRXI HI EYXSMRHY±­S HE FSFMRE 1 QEMW WI JEV­S WIRXMV SW IJIMXSW HE EYXSMRHY±­S TIPS UYI QI RSV WIV« E GSVVIRXI RS GMVGYMXS & GSVVIRXI WIV« MRZIVWEQIRXI TVSTSV GMSREP ª MRHYX¬RGME &REPMWERHS S GSQTSVXEQIRXS HE VIEX¬RGME MRHYXMZE TEVE YQE KVERHI JVIUY´RGME SY WINE YQ TIUYIRS TIV¸SHS E GSVVIRXI R­S XIQ XIQTS HI EXMRKMV S WIY ZEPSV Q«\MQS TSMW E XIRW­S ETPMGEHE MRZIVXI WI 6YERXS QEMSV JSV E JVIUY´RGME QIRSV WIV« E GSVVIRXI IP³XVMGE & IUYE±­S WIKYMRXI HIǻRI E KVERHI^E VIEX¬RGME MRHYXMZE <1 UYI ³ E STSWM±­S HE FSFMRE ª TEWWEKIQ HE GSVVIRXI IP³XVMGE XL = ƍ ƽ J ƽ 1 SRHI

J ³ E JVIUY´RGME HS WMREP HI EPMQIRXE±­S IQ -IVX^ -^

1 ³ S GSIǻGMIRXI HI EYXSMRHY±­S SY MRHYX¬RGME HE FSFMRE

IQ -IRV] -

16

MANUTENÇÃO 136

9Q I\IQTPS HI YQ GMVGYMXS VIEP MRHYXMZS ³ YQ XVERWJSVQEHSV QSRSJ« WMGS 9Q XVERWJSVQEHSV ³ YQ HMWTSWMXMZS GSRWXMXY¸HS TSV HYEW FSFMREW GSQ EGSTPEQIRXS QEKR³XMGS XSXEP YXMPM^EHS TEVE E XVERWJSVQE±­S HI XIRWÀIW 6YERHS ³ ETPMGEHE YQE XIRW­S EPXIVREHE RS IRVSPEQIRXS TVM Q«VMS SFXIQSW YQE XIRW­S UYI TSHIV« EWWYQMV YQE EQTPMXYHI QEMSV SY QIRSV HITIRHIRHS WI S XVERWJSVQEHSV ³ IPIZEHSV SY EFEM\EHSV VIWTIXMZEQIRXI RS IRVSPEQIRXS WIGYRH«VMS 5EVE E ER«PMWI HIWXI XMTS HI GMVGYMXSW GSRWMHIVIQSW E +MKYVE SRHI MVIQSW GEPGYPEV • & VIEX¬RGME GETEGMXMZE • & MQTIH¬RGME HS GMVGYMXS • & MRXIRWMHEHI HI GSVVIRXI UYI TIVGSVVI E VIWMWX´RGME I E FSFMRE • & XIRW­S ESW XIVQMREMW HE VIWMWX´RGME I HE FSFMRE • 4 ¬RKYPS HI HIWJEWEQIRXS IRXVI E XIRW­S I E GSVVIRXI

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UT = 230 V, 50 Hz

0,16 H

R

L

UR

UL

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Figura 79. Circuito RL em análise.

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