Methodology for estimating reception efficiency of mutually correlated or in- phase signals at diversity transmission

The article describes and theoretically substantiates the potential technical capabilities of spatially separated earth stations (ES). When several ESs emit in-phase or mutually pairwise correlated signals in the direction of one received antenna of the object, the total level of the sum of emissions at its output (at the input of the receiving path) may be several times higher than the sum of the powers of these signals. In this regard, the article investigates the influence of the phase difference of the transmitted signals on the value of their total average power at the input of the receiving path. In the case of addition of common-mode signals, a formula is used to calculate in which the power of harmonic radiation is proportional to the square of the sum of the amplitude of the common-mode signals. This paradox is also valid for pairwise cross-correlated signals. The presented technique for evaluatingтthe effectivenessтallows one to establish not only the dependence of the energy ratios on the nonтenergy parameter, but also to determine the number of low-power ESs required to ensureтthe required signal level at the input of the receiving device. The use of the presented technique makes it possible to evaluate the efficiency of receiving a combined high-power signal for a differentтnumber of emitters that form in-phase or pairwise mutual correlation of signals at the receiving point.

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Using Both the Circulating Currents and the Common-Mode Voltage for the Branch Energy Control of Modular Multilevel Converters

2020 22nd European Conference on Power Electronics and Applications (EPE'20 ECCE Europe) ◽

10.23919/epe20ecceeurope43536.2020.9215845 ◽

2020 ◽

Author(s):

Rebecca Dierks ◽

Jakub Kucka ◽

Axel Mertens

Keyword(s):

Energy Control ◽

Multilevel Converters ◽

Common Mode ◽

Common Mode Voltage ◽

Modular Multilevel Converters ◽

The Common ◽

Circulating Currents

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Low Common-Mode Noise Structure Based on Half-Bridge LLC Converter for Medium and High Power Applications

2020 IEEE 9th International Power Electronics and Motion Control Conference (IPEMC2020-ECCE Asia) ◽

10.1109/ipemc-ecceasia48364.2020.9367818 ◽

2020 ◽

Author(s):

Keon-Woo Kim ◽

Yeonho Jeong ◽

Jae-Sang Kim ◽

Jeong-Eon Park ◽

Gun-Woo Moon

Keyword(s):

High Power ◽

Common Mode ◽

Noise Structure

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Tunable balanced to balanced filtering power divider with high common-mode suppression

Frequenz ◽

10.1515/freq-2019-0178 ◽

2020 ◽

Vol 74 (7-8) ◽

pp. 263-270

Author(s):

Cao Zeng ◽

Xue Han Hu ◽

Feng Wei ◽

Xiao Wei Shi

Keyword(s):

Return Loss ◽

High Selectivity ◽

Power Divider ◽

Center Frequency ◽

Differential Mode ◽

Common Mode ◽

Mode Suppression ◽

The Common ◽

Equal Power ◽

Good Agreement

AbstractIn this paper, a tunable balanced-to-balanced in-phase filtering power divider (FPD) is designed, which can realize a two-way equal power division with high selectivity and isolation. A differential-mode (DM) passband with a steep filtering performance is realized by applying microstrip stub-loaded resonators (SLRs). Meanwhile, six varactors are loaded to the SLRs to achieve the center frequency (CF) and bandwidth adjustment, respectively. U-type microstrip lines integrated with stepped impedance slotline resonators are utilized as the differential feedlines, which suppress the common-mode (CM) intrinsically, making the DM responses independent of the CM ones. A tuning center frequency from 3.2 to 3.75 GHz and a fractional bandwidth (12.1–17.6%) with more than 10 dB return loss and less than 2.3 dB insertion loss can be achieved by changing the voltage across the varactors. A good agreement between the simulated and measured results is observed. To the best of authors' knowledge, the proposed balanced-to-balanced tunable FPD is first ever reported.

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Modulating 2D Heterointerface with g-C3N4 Meshes: A Suitable Hetero-Layered Architecture for High-Power and Long-Life Energy Storage

Journal of Materials Chemistry A ◽

10.1039/d0ta12497d ◽

2021 ◽

Author(s):

Yunping Wu ◽

Wei Wei ◽

Tianyi Ding ◽

Sheng Chen ◽

Rui Zhai ◽

...

Keyword(s):

Energy Storage ◽

High Power ◽

2D Materials ◽

Two Dimensional ◽

Energy Storage Devices ◽

Storage Devices ◽

Efficient Energy ◽

Layered Architecture ◽

The Common ◽

Long Life

Two-dimensional (2D) heterostructures combine the advantageous features of different 2D materials and represent advanced electrode architectures for development of efficient energy storage devices. However, the common 2D heterostructures made by...

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Reactive High-Power Impulse Magnetron Sputtering of Chromium-Carbon Films

Coatings ◽

10.3390/coatings10121269 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1269

Author(s):

Chin-Chiuan Kuo ◽

Chun-Hui Lin ◽

Jing-Tang Chang ◽

Yu-Tse Lin

Keyword(s):

Magnetron Sputtering ◽

Amorphous Carbon ◽

High Power ◽

Deposition Temperature ◽

Average Power ◽

Carbon Films ◽

Strengthening Effect ◽

Substrate Bias ◽

Hydrogenated Amorphous Carbon ◽

Hydrogenated Amorphous

Chromium-carbon films were deposited by utilizing reactive high-power impulse magnetron sputtering at different mixture ratios of ethyne and argon atmosphere, and different substrate bias voltages and deposition temperature, with the same pulse frequency, duty cycle, and average power. The microstructure and mechanical properties of the obtained films were compared. The films consist of amorphous or nanocrystalline chromium carbide, hydrogenated amorphous carbon, and minor α-chromium phase. Decreasing the fraction of ethyne increases the content of the α-chromium phase but decreases hydrogenated amorphous carbon phase. The film’s hardness increases by enhancing the negative substrate bias and raising the deposition temperature, which could be attributed to the increase of film density and the Hall–Petch strengthening effect induced by the nanoscale crystallization of the amorphous carbide phase.

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A New Approach to the PWM Modulation for the Multiphase Matrix Converters Supplying Loads with Open-End Winding

Energies ◽

10.3390/en14020466 ◽

2021 ◽

Vol 14 (2) ◽

pp. 466

Author(s):

Pawel Szczepankowski ◽

Natalia Strzelecka ◽

Enrique Romero-Cadaval

Keyword(s):

Pulse Width Modulation ◽

Harmonic Distortion ◽

Simulation Software ◽

Common Mode ◽

New Approach ◽

Matrix Converters ◽

Load Voltage ◽

Common Mode Voltage ◽

The Common ◽

Open End Winding

This article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load’s terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion (THD) of the generated load voltage. The third variant of modulation concerns maximizing the voltage transfer ratio, minimizing the number of switching, and the common-mode voltage cancellation. The discussed modulations are based on the concept of sinusoidal voltage quadrature signals, which can be an effective alternative to the classic space-vector approach. In the proposed approach, the geometrical arrangement of basic vectors needed to synthesize output voltages is built from the less number of vectors, which is equal to the number of the matrix converter’s terminals. The PWM duty cycle computation is performed using only a second-order determinant of the voltages coordinate matrix without using trigonometric functions. A new approach to the PWM duty cycles computing and the load voltage synthesis by 5 × 5 and 12 × 12 topologies has been verified using the PSIM simulation software.

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Opposite Triangle Carrier with SVPWM for Common-Mode Voltage Reduction in Dual Three Phase Motor Drives

Energies ◽

10.3390/en14020282 ◽

2021 ◽

Vol 14 (2) ◽

pp. 282

Author(s):

Seon-Ik Hwang ◽

Jang-Mok Kim

Keyword(s):

Electromagnetic Interference ◽

Pulse Width Modulation ◽

Motor Drives ◽

Common Mode ◽

Pwm Inverter ◽

Common Mode Voltage ◽

Voltage Vector ◽

Three Phase ◽

The Common ◽

Zero Voltage

The common-mode voltage (CMV) generated by the switching operation of the pulse width modulation (PWM) inverter leads to bearing failure and electromagnetic interference (EMI) noises. To reduce the CMV, it is necessary to reduce the magnitude of dv/dt and change the frequency of the CMV. In this paper, the range of the CMV is reduced by using opposite triangle carrier for ABC and XYZ winding group, and the change in frequency in the CMV is reduced by equalizing the dwell time of the zero voltage vector on ABC and XYZ winding group of dual three phase motor.

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