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In stable electrical networks, such as the German one, the service of uninterruptible power supply (UPS) systems is only rarely called. Consequently the battery lifetime in this application is mostly restricted by calendar aging. The concept of multi-use describes here the delivery of additional services with a UPS during stable grid operation. The overall goal is to allocate the battery capacity...
The paper presents an original numerical-analytical method of fault location and the calculation of transverse resistance of a fault in a damaged medium voltage cable. The method is based on the measurement of input impedances for two different frequencies at one end of the cable with an open state at its other end. The proposed method was compared with the reflectometry. The effectiveness of the...
SAW sensors offer a mechanical motion in MHz to GHz range and can be immune to effects from boundary loss through the bulk and edges. SAW based gyroscopes have been implemented by added masses which impose an effect on wave prorogation fronts through the Coriolis force. A key challenge in implementing SAW based gyroscopes is to improve the sensitivity owing to small forces and SAW signals. significant...
Frequency Response Analysis (FRA) has been used as a comparative diagnosis method to explore mechanical defects in transformer. FRA is quite sensitive method and it can be influenced by different factors in transformer simply; however, this sensitivity will make it superior rather than other transformer winding deformation diagnosis techniques. This study has concentrated on tap-changer position influence...
This paper focuses to the problematic of thin film metal layers. The samples prepared by vacuum evaporation of thin film meander-shaped aluminium layers were analysed. Electrical resistance and thickness of layer were included in the measured parameters. We evaluated these parameters in dependence of the volume of the source material, i.e., an aluminium wire. We observed a certain variance in measured...
Due to the rising electrification, there is a need for innovative charging technologies to keep pace with technological progress and tethered charging. The electrical performance of wireless power transfer (WPT) systems is one crucial point in charging electric vehicles. The resonance frequency respectively the switching frequency of the converter has a large impact on system behavior. Due to component...
Microstrip antennas are highly resonant structures and, for simple patch configurations, the bandwidths of each mode is quite small. As an antenna, their most useful mode is the TM11 mode that radiates in the broadside direction with a good gain. All other modes, TMnm, radiate conical beams with a null in the broadside and have a pattern peak that moves towards the endfire direction by increasing...
Wound aluminum foils are traditionally known to be used for the construction of capacitors and with some difference in the arrangement for the construction of foil wound inductors. It is further known that a specific connection of the supply terminals to the ends of the aluminum foils yields capacitance and inductance at the same time. Wound aluminum foils comprising inductance and capacitance in...
An absolute electrical substitution radiometer is a way to ensure highly accurate and stable measurement of optical power in a wide range of optical wavelengths. Its sensitivity is mainly determined by the temperature stability of the equithermal bath and the electrical noise of the temperature readout. In this article we investigate the noise background of different preamplifiers in combination with...
Considering the existing measurement method in mine's power system can not accurately distinguish ground insulation resistance and earth capacity, a new measurement method based on additional low frequency signal is proposed. The insulation resistance and earth capacity can be calculated by the new method based on additional low frequency signal. By MATLAB simulation technology, analysis result and...
In this paper we present a method for sensing of chemical vapour based on scaling of resistance fluctuation of single layer graphene (SLG) field effect transistors. Increase of variance of resistance fluctuation of device in presence of chemical vapour makes noise a very sensitive tool for detection. Analysis of the effect of presence of chemicals in the ambience of graphene on the 1/f noise spectrum...
This paper presents a study of the radiation efficiency measurement of antennas using the source stirred chamber (SSC) method. The antenna under test (AUT) was a coplanar-line-fed monopole. By using the minimum value of the input resistance of the antenna in the chamber under different stirring configurations and introducing frequency stirring technique, the resonance effect can be greatly reduced...
Eddy current testing (ECT) has been widely used for the nondestructive evaluation of metallic plates or pipes. One of the methods in ECT is to measure the change of coil impedance that is caused by the metallic plate below the coil. We applied this method to estimate the thickness of an iron plate. In this case, low-frequency measurement is required in order to avoid the skin effect. At low frequencies,...
In order to improve the bias stabilities in different temperature for silicon resonant accelerometer (SRA), a temperature measurement method, which measure Temperature in package cavity, was proposed based on chip integrated temperature resonator. Firstly, the frequency-temperature characteristics of the resonators in SRA is analyzed. Afterwards, the heat transfer model for SRA based on chip integrated...
A new method to measure the polarization resistance on electrochemical cells is proposed. The method is based on the application of a new pulsed excitation, which exhibits low pass frequency contents, and time domain analysis. In other pulsed excitation methods, curve fitting algorithms are used to find values for equivalent RC models. In our approach using this pulsed excitation, single values of...
In this paper realization of digital LCR meter is presented. Realized system is based on integrated circuit AD5933 which is controlled by microcontroller ATmega128. Device can calculate resistance, capacitance and inductance of the device under test as well as Dissipation and Quality factors. Operating frequency range is from 5 to 100 kHz with frequency sweep function in maximum 511 steps. Device...
Magnetic materials made of iron-powder that are used for the cores of the chokes of voltage source inverters output filters significantly change their power losses and magnetic properties with the frequency and the amplitude of the choke current in the range that is important for designers. This causes the magnitude Bode plot of the VSI control transfer function to have a higher damping coefficient...
We developed a trial model of a 1-kΩ metal-foil resistor with a four-terminal-pair design. The resistance and phase angle of the resistor as a function of frequency were measured. Below a 2-kHz frequency, a slight quadratic change in the resistance was observed. The phase-angle results showed a linear change, and the time constant was estimated from the slope of the linear change.
Ultra-broadband chip-to-chip interconnects at high frequencies are demonstrated. These interconnects, based on the Quilt Packaging (QP) approach, appear to be promising for applications in millimeter-wave circuits due to their extremely wide bandwidth and ease of assembly. The performance of chip-to-chip interconnects in a 50 Ω coplanar waveguide environment on high-resistivity silicon substrates...
This paper presents the modeling, design, fabrication and characterization, up to 30 GHz, of low loss and high aspect-ratio 55 μm diameter through package vias (TPVs) in 300 μm thick glass interposers. These TPVs were fabricated using a novel, high-throughput, focused electrical discharge method and low cost panel-based double-side metallization processes. Such a glass interposer is targeted at two...
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