CARLOS ANTONIO FRANCA SARTORI
14 resultados
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Artigo IPEN-doc 29314 Compatibilidade e resiliência eletromagnética em sistemas elétricos e eletrônicos2022 - ROQUE, ACASSIO M.; SARTORI, CARLOS A.Artigo IPEN-doc 27752 A parametric study of inductive SWIPT systems assisted by metamaterial using virtual magnetic TL-based channel modeling2021 - ALMEIDA, JORGE V. de; SILVA, EDUARDO C. da; MOSSO, MARBEY M.; SARTORI, CARLOS A.F.This paper presents a general methodology based on the description of the inductive channel as virtual magnetic transmission-lines (VMGTLs). In comparison with other existing methods, VMGTL approach presents a better physical insight of the channel behavior since the model correctly preserves the energy flow between the transmitting and receiving coils. Besides that, it facilitates the integration into the analysis of highly nonlinear and dispersive structures such as metamaterial (MTM) lenses. Particularly, the virtual-TL analogy clarifies that the enhancement of the transmission gain between any two coils assisted by MTM is not due to an enhanced coupling between the drivers, as usually claimed, but to the emergence of propagating near-field modes supported by the MTM. This approach, by means of a parametric study, also indicates, for the first time, that MTMs could be employed not only for the increasing of power but also of data transfer due to the emergence of a sub-resonant region of minimum distortion. Nonetheless, since both effects are mutually exclusive, no passive MTM structure could simultaneously improve power and data transmission.Artigo IPEN-doc 25910 Modeling of a metamaterial in the FEA of a contactless transcutaneous energy transfer device2018 - CARVALHO, G.D.; SILVA, V.C.; HAFFNER, F.; SARTORI, C.A.F.; LEBENSZTAJN, L.; KRAHENBUHL, L.Metamaterials are difficult to deal with in computational electromagnetic modelling, e.g. finite element analysis. The reason is the prohibitive discretization refinement needed to account for their actual electromagnetic field distribution profile, within the frequency range used in contactless energy transfer devices. We propose an approach to simplify the modeling of a metamaterial in finite element simulations and present an analysis of its impact in the evaluation of the magnetic field distribution in the vicinity of the metamaterial.Artigo IPEN-doc 24969 Impact of mismatch cables impedances on active motor terminal overvoltage mitigation using parallel voltage source inverters2017 - SANTOS, DANIEL de P. dos; SARTORI, CARLOS A.F.Non-treated transient motor terminal overvoltage due high-speed switching sources and long cable length can be twice the original source voltage amplitude. In some cases, this overvoltage can cause premature motor insulation failure. A topology widely applied in industry is subject of this overvoltage: motors driven by voltage source inverter, connected by long feeding cable. There are several passive methods effective in mitigating overvoltage, but most of them are based in lossy and bulky passive component filters. A different approach is proposed by two low loss active methods for overvoltage mitigation with simple topologies. It consists in using voltage source inverters with specific switching strategy in order to attenuate the main cause of overvoltage: the superposition of traveling reflected pulses at the motor terminals. As promising methods for overvoltage mitigation, some specific studies regarding its particularities must be carried on in order to clear understand all its benefits and possible drawbacks. The present paper discusses the vulnerability of these overvoltage mitigation methods to some internal parameter variation. The impact of cables impedance variation due heating –and impedance mismatch– is highlighted, since it is intrinsic to the system and can degrades overvoltage mitigation.Artigo IPEN-doc 24935 Low-voltage AC surge protective device assessment regarding nuclear plants2017 - BORSOI, SAD S.; O. NETO, JESUS A.; PEREIRA, CARLOS E.M.; SARTORI, CARLOS A.F.This paper presents a methodology for low-voltage AC surge protective device (SPD) coordination. As motivation, the required nuclear plant reliability and safety criteria, in which the surge protection coordination can assume an important role, are emphasized. Due to the characteristics of the protection system, and the surge phenomena, an iterative methodology is applied. The SPD selection and specifications are based on the equipment immunity level, insulation and on SPD characteristics, like absorbed energy. Some results are presented and discussed, showing the suitability of the proposed methodology.Artigo IPEN-doc 05803 Evaluation of electromagnetic environment around a structure during a lightning stroke1994 - SARTORI, C.A.F.; CARDOSO, J.R.Artigo IPEN-doc 05804 Evaluation of electromagnetic environemnt around a structure during a lightning stroke1994 - SARTORI, C.A.F.; CARDOSO, J.R.Artigo IPEN-doc 05801 Evaluation of electromagnetic environment around a structure during a lightning stroke1994 - SARTORI, C.A.F.; CARDOSO, J.R.Artigo IPEN-doc 05802 Evaluation of electromagnetic environment around a structure during a lightning stroke1994 - SARTORI, C.A.F.; CARDOSO, J.R.Artigo IPEN-doc 05800 A method for calculating the current distribution and magnetic field around a lightning stroked structure1994 - SARTORI, C.A.F.; CARDOSO, J.R.