ESPAÇO DE FORMAÇÃO

Ficha técnica n.o 13 {±ƚĬŅ{åĜƻŅƋŅ TEYPSTIM\SXS%EXIGTX &8*(Ƴ&GEHIQMEHI+SVQE±­S

11. ANÁLISE DE CIRCUITOS EM CORRENTE ALTERNADA (PARTE 2) 11.3.2. Circuito indutivo em corrente alternada 3SWGMVGYMXSW TYVEQIRXI MRHYXMZSW E STSWM±­S ª GMVGYPE±­S HE GSV VIRXI³JIMXETIPE+SV±E*PIXVSQSXVM^ JIQHIEYXSMRHY±­SHEFSFM REIGLEQEWIVIEX¬RGMEMRHYXMZE < 1 II\TVMQIWIIQǞ &REPMWERHSYQGMVGYMXSGSQYQEFSFMREIQGSVVIRXIGSRX¸RYETS HIQSWZIVMǻGEVSIJIMXSHE1IMHI1IR^&WWMQUYERHSSMRXIVVYTXSV³ JIGLEHSGVMEVWI«YQEGSVVIRXIIP³XVMGEMRHY^MHERSGMVGYMXSGYNSWIR XMHSWISTÀIQªGSVVIRXITVMRGMTEPVIXEVHERHSEWWMQSWIYMR¸GMS5IPS GSRXV«VMS UYERHS WI EFVI S MRXIVVYTXSV XEQF³Q TIPE 1IM HI 1IR^ E GSVVIRXIR­SGIWWEV«HIMQIHMEXSTSMWWYVKMV«YQEGSVVIRXIMRHY^MHE UYIEVIXEVHEV«&+MKYVEVITVIWIRXEIWXIIJIMXS

&SETPMGEVQSWYQEXIRW­SEYQEFSFMREEGSVVIRXIR­SWYVKMV«MQI HMEXEQIRXI TSMW GSQS EREPMWEHS ERXIVMSVQIRXI WYVKMV« RS GMVGYMXS HIZMHSªEYXSMRHY±­SYQEGSVVIRXIGSQYQWIRXMHSXEPUYIJE^VIXEV HEVSETEVIGMQIRXSHEGSVVIRXITVMRGMTEPRSGMVGYMXS*WXEETIREWETE VIGIV«UYERHSEXIRW­SEXMRKMVSWIYZEPSVQ«\MQS&MRHEHIZMHSESW JIR¾QIRSWHIEYXSMRHY±­SEGSVVIRXIMV«EYQIRXEVIRUYERXSEXIRW­S HIGVIWGIIEXMRKIYQQ«\MQSUYERHSEXIRW­SETPMGEHE³RYPE6YER HSEXIRW­SMRZIVXISWIYWIRXMHSEGSVVIRXIGSQI±EEHMQMRYMVQEW IWXEHMQMRYM±­S³VIXEVHEHEIERYPEWIUYERHSEXIRW­SEXMRKISWIY Q«\MQSRIKEXMZSSYWINEYQUYEVXSHITIV¸SHSQEMWXEVHI &+MKYVEETVIWIRXESHIWJEWEQIRXSHESRHEHEXIRW­SIHEGSV VIRXIRYQGMVGYMXSTYVEQIRXIGETEGMXMZSSRHITSHIVIQSWEREPMWEVUYI EGSVVIRXIIWX«EXVEWEHE}IQVIPE±­SªXIRW­S

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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.

*QGSVVIRXIEPXIVREHESWIJIMXSWHEEYXSMRHY±­SW­SGSRWXERXIW5S HIQSWGSRGPYMVUYIUYERXSQEMSVJSVSGSIǻGMIRXIHIEYXSMRHY±­SHE FSFMRE 1QEMWWIJEV­SWIRXMVSWIJIMXSWHEEYXSMRHY±­STIPSUYIQI RSVWIV«EGSVVIRXIRSGMVGYMXS&GSVVIRXIWIV«MRZIVWEQIRXITVSTSV GMSREPªMRHYX¬RGME &REPMWERHS S GSQTSVXEQIRXS HE VIEX¬RGME MRHYXMZE TEVE YQE KVERHIJVIUY´RGMESYWINEYQTIUYIRSTIV¸SHSEGSVVIRXIR­SXIQ XIQTSHIEXMRKMVSWIYZEPSVQ«\MQSTSMWEXIRW­SETPMGEHEMRZIVXIWI 6YERXSQEMSVJSVEJVIUY´RGMEQIRSVWIV«EGSVVIRXIIP³XVMGE &IUYE±­SWIKYMRXIHIǻRIEKVERHI^EVIEX¬RGMEMRHYXMZE <1UYI³ ESTSWM±­SHEFSFMREªTEWWEKIQHEGSVVIRXIIP³XVMGE XL =ƍƽJƽ1 SRHI  J ³EJVIUY´RGMEHSWMREPHIEPMQIRXE±­SIQ-IVX^ -^  1 ³SGSIǻGMIRXIHIEYXSMRHY±­SSYMRHYX¬RGMEHEFSFMRE   IQ-IRV] -

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MANUTENÇÃO 136

9QI\IQTPSHIYQGMVGYMXSVIEPMRHYXMZS³YQXVERWJSVQEHSVQSRSJ« WMGS9QXVERWJSVQEHSV³YQHMWTSWMXMZSGSRWXMXY¸HSTSVHYEWFSFMREW GSQEGSTPEQIRXSQEKR³XMGSXSXEPYXMPM^EHSTEVEEXVERWJSVQE±­S HI XIRWÀIW6YERHS³ETPMGEHEYQEXIRW­SEPXIVREHERSIRVSPEQIRXSTVM Q«VMSSFXIQSWYQEXIRW­SUYITSHIV«EWWYQMVYQEEQTPMXYHIQEMSV SY QIRSV HITIRHIRHS WI S XVERWJSVQEHSV ³ IPIZEHSV SY EFEM\EHSV VIWTIXMZEQIRXIRSIRVSPEQIRXSWIGYRH«VMS5EVEEER«PMWIHIWXIXMTS HIGMVGYMXSWGSRWMHIVIQSWE+MKYVESRHIMVIQSWGEPGYPEV • &VIEX¬RGMEGETEGMXMZE • &MQTIH¬RGMEHSGMVGYMXS • &MRXIRWMHEHIHIGSVVIRXIUYITIVGSVVIEVIWMWX´RGMEIEFSFMRE • &XIRW­SESWXIVQMREMWHEVIWMWX´RGMEIHEFSFMRE • 4¬RKYPSHIHIWJEWEQIRXSIRXVIEXIRW­SIEGSVVIRXI

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Figura 79. Circuito RL em análise.

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