The Short-Circuit Input Impedance as a Main Source of Input-Filter Interactions in a Regulated Converter

A meandered-dual-antenna structure is proposed for UHF radiofrequency identification (RFID) tag. It is composed of two independent antennas printed on the one side of the substrate board. One of the antennas is exclusively used for receiving and harvesting sufficient energy to the tag chip having the complex conjugate impedance of the receiving antenna. The other is for backscatter to enhance maximum differential radar cross-section with purely real input impedance, to enhancement the read range. The receiving antenna is formed by a rectangular loop and a parasitic meandered line. The rectangular loop is used as a feeding element for the meandered line. The backscattering antenna is made using a meandered dipole along with a thin rectangular strip. The input impedance of the receiving antenna is designed to be conjugate matched to the chip impedance (13.5-j110 Ω), whereas the input impedance of backscattering antenna alternatively switched to open and short circuit for modulating the backscattered field. The input impedance of receiving and backscattering antennas is measured using differential probe technique. The simulated and measured results are found in good agreement. It is also demonstrated that the read range of UHF RFID system increased considerably by using the dual-antenna structure.

Download Full-text

A Three-phase to three-phase matrix converter prototype

Sba Controle & Automação Sociedade Brasileira de Automatica ◽

10.1590/s0103-17592012000300001 ◽

2012 ◽

Vol 23 (3) ◽

pp. 247-262 ◽

Cited By ~ 2

Author(s):

Milton E. de Oliveira Filho ◽

Alfeu J. Sguarezi Filho ◽

Ernesto Ruppert

Keyword(s):

Short Circuit ◽

Matrix Converter ◽

Semiconductor Switches ◽

Input Filter ◽

Three Phase

This paper presents some implementation details of a three-phase to three-phase matrix converter prototype. The bidirectional semiconductor switches were built using discrete IGBTs and fast diodes. Design aspects such as protection against overvoltage and short-circuit, commutation process of bi-directional switches, and input filter are addressed in this paper.

Download Full-text

On the equivalent circuit, input impedance, reflection coefficient, and bandwidth of printed monopole antenna

Microwave and Optical Technology Letters ◽

10.1002/mop.29130 ◽

2015 ◽

Vol 57 (7) ◽

pp. 1535-1538

Author(s):

S. Bhattacharjee ◽

R. S. Kshetrimayum ◽

R. Bhattacharjee

Keyword(s):

Reflection Coefficient ◽

Equivalent Circuit ◽

Input Impedance ◽

Monopole Antenna ◽

Circuit Input ◽

Printed Monopole Antenna ◽

Printed Monopole

Download Full-text

Measure of high frequency input impedance to study the instability of power devices in short circuit

Microelectronics Reliability ◽

10.1016/j.microrel.2018.07.035 ◽

2018 ◽

Vol 88-90 ◽

pp. 540-544

Author(s):

C. Abbate ◽

G. Busatto ◽

A. Sanseverino ◽

D. Tedesco ◽

F. Velardi

Keyword(s):

High Frequency ◽

Input Impedance ◽

Short Circuit ◽

Power Devices

Download Full-text

Structural Imperfections in thin Oxide Films Formed on Some Fe- and Ni-Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069545 ◽

1970 ◽

Vol 28 ◽

pp. 510-511

Author(s):

L. P. Lemaire ◽

D. E. Fornwalt ◽

F. S. Pettit ◽

B. H. Kear

Keyword(s):

Oxide Scale ◽

Oxidation Process ◽

Short Circuit ◽

Protective Oxide ◽

Protective Oxide Scale ◽

Thin Oxide Films ◽

Diffusion Paths ◽

Oxidation Resistant ◽

Structural Imperfections ◽

Short Circuit Diffusion

Oxidation resistant alloys depend on the formation of a continuous layer of protective oxide scale during the oxidation process. The initial stages of oxidation of multi-component alloys can be quite complex, since numerous metal oxides can be formed. For oxidation resistance, the composition is adjusted so that selective oxidation occurs of that element whose oxide affords the most protection. Ideally, the protective oxide scale should be i) structurally perfect, so as to avoid short-circuit diffusion paths, and ii) strongly adherent to the alloy substrate, which minimizes spalling in response to thermal cycling. Small concentrations (∼ 0.1%) of certain reactive elements, such as yttrium, markedly improve the adherence of oxide scales in many alloy systems.

Download Full-text