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
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t Figura 78. Representação vetorial e cartesiana da tensão e respetiva corrente num circuito
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11.3.3. Circuito indutivo real – Circuito RL U
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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] -
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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
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Figura 79. Circuito RL em análise.
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