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Showing 1 to 20 of 34 for “"equivalent circuits"”.
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Equivalent circuits of thermoelectric coolers.
Equivalent circuits are useful for simplified representation and deeper understanding of electrical devices. In this work a thermoelectric system is represented by equivalent circuits. The first part of work is introductory. It contains the definitions and derivations of the various thermoelectric …
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Utilizing equivalent circuits to describe the strain- and temperature-dependence of electromagnetic metamaterials
… to fielded capability. This study leverages equivalent circuit models to understand and predict the strain- and temperature-dependent EM properties of metamaterial structures. Straightforward analytic expressions for the equivalent circuit parameters (resistance, inductance, capacitance) …
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Resonant Gate Drive Techniques for Power MOSFETs
With the use of the simplistic equivalent circuits, loss mechanism in conventional power MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) gate drive circuits is analyzed. Resonant gate drive techniques are investigated and a new resonant gate drive circuit is presented. The presented …
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Transient analysis of lossy multiconductor transmission lines in nonlinear circuits
… each time step by discretized Thevenin or Norton equivalent circuits. Because these models contain only lumped elements, they can be easily implemented in a general circuit analysis program for simulating the transient responses of nonlinear circuits. The analysis procedure developed makes …
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Integration of Filter Elements in Electric Drives
… inductor design is done using magnetic equivalent circuits and examined with finite element analysis. Rotor inertia is used to displace electrical passive components and thereby reduce the filter requirements of the dc-link capacitor. This is shown in permanent magnet synchronous machine …
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Equivalent electrical circuits for structural problems
… therefore, it is conceivable that electrical circuits may be devised which are equivalent to certain structural problems. It is the purpose of this thesis to set up several equivalent circuits and to present solutions using accepted methods of analysis. Only statistical loadings are …
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Multimode and Multiband Microstrip Antennas
… bandwidth can be significantly increased. The equivalent circuit of such structures is similar to those used in microwave filter design. Using techniques normally employed in filter synthesis, the equivalent circuits can be generated, and aid in finding the couplings and dimensions of the …
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Novel techniques for improved indoor positioning and localization using HF RFID
… objects etc, we proposed methods of improvement. Equivalent circuits that reduce the computational complexity but can provide a broader understanding of the behaviour of bridge antennas have been formulated. This has lead to investigation of methods to minimise and/or eliminate the effect of …
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Derivation of Moving-Coil Loudspeaker Parameters Using Plane Wave Tube Techniques
… apparatus, and system modeling methods (via equivalent circuits). It also compares measured parameters to those derived using electrical techniques. Parameters derived from both approaches are compared with reference values to establish bias errors. Sequential measurements are also compared …
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Synthesis and characterization of conducting polymer actuators
… with temperature. Discrete time models of equivalent circuits and diffusion are utilized to predict conducting polymer actuator performance.
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High-frequency, high-pole count design for improving specific power density of electric machines
… and permanent magnet machines. Electrical equivalent circuits are utilized to analytically hypothesize the effect of HFHP designs, then finite element models (FEM) are built to verify the effects. For induction machines, significant reduction in magnetizing reactance is shown to result in …
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Characterization of Ferroelectric Films by Spectroscopic Ellipsometry
… phase Bi₂O₃ produced elevated leakage currents. Equivalent circuits and percolation theory were applied to predict leakage current based on Bi₂O₃ content and connectivity. The complex role of excess Bi2O3 in the crystallization of SBT was reviewed from a processing perspective. VASE helped …
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Optimal Control of a Stepping Motor
… motors in terms of electrical and magnetic equivalent circuits. ‘Exact’ and simplified models for a permanent magnet motor are presented, and simple linear end non-linear models are used to theoretically optimise the input variables. The second part (chapters 5-6) is devoted to the drive …
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Reduced-order modeling of power electronics components and systems
… component level, dynamic high-fidelity magnetic equivalent circuits are introduced for laminated and solid magnetic cores. Automated linear and nonlinear order-reduction techniques are introduced for linear magnetic systems, saturated systems, systems with relative motion, and multiple-winding …
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NiMH battery forensics: Instrumentation, modelling and prognostics for identifying failure
… the internal component values of the battery equivalent circuits. The bulk-surface model was determined to be the most appropriate for the Toyota Prius battery modules as the EKF predicted component values converge to stable values, and the recovered voltage trace has a low error. However, the …
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Modeling and Characterization of Power Electronic Converters with an Integrated Transmission-Line Filter
… MOSFETs, and the gate driver. In addition, equivalent circuits were used to characterize high frequency impedances of the passive components. A PFC boost converter was built and used to validate the model. The PFC operated at a peak output power of 1 kW, switching at 400 kHz, with a …
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New Multi-Phase Diode Rectifier Average Models for AC and DC Power System Studies
… in the output impedance in contrast in the equivalent commutation inductance. The average model is applied to the resonance study in a system composed of a synchronous generator, a nine-phase diode rectifier and a motor drive. The Thevenin's and Norton's equivalent circuits are derived to …
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Implementing Electrochemical Impedance Spectroscopy for the In Situ Analysis Of Conducting-Membrane Fouling
… fouling, EIS spectra were interpreted by fitting equivalent circuits informed by the physical structures of the membrane surface and interior. </p><p>Data from the EIS fouling tests showed good agreement between changes in impedance, conductance, and capacitance and reduction in permeate flow, …
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Design and Analysis of Piezoelectric Transformer Converters
… linear or nonlinear loads, suitable electrical equivalent circuits are required for the frequency range of interest. The study of the accuracy of PT models is carried out and verified from several points of view, including input impedance, voltage gain, and efficiency. From the characteristics …
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