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Wang, X. (author), Bauer, G.E.W. (author), Hoffman, A. (author)
journal article 2006
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Wang, X. (author), Bauer, G.E.W. (author), Van Wees, B.J. (author), Brataas, A. (author), Tserkovnyak, Y. (author)
A ferromagnet can resonantly absorb rf radiation to sustain a steady precession of the magnetization around an internal or applied magnetic field. We show that, under these ferromagnetic resonance conditions, a dc voltage is generated at a normal-metal electric contact to a ferromagnet with spin-flip scattering. The spin dynamics in the...
journal article 2006
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Klimczuk, T. (author), Wang, C.H. (author), Lawrence, J.M. (author), Xu, Q. (author), Durakiewicz, T. (author), Ronning, F. (author), Llobet, A. (author), Trouw, F. (author), Kurita, N. (author), Tokiwa, Y. (author), Lee, H. (author), Booth, C.H. (author), Gardner, J.S. (author), Bauer, E.D. (author), Joyce, J.J. (author), Zandbergen, H.W. (author), Movshovich, R. (author), Cava, R.J. (author), Thompson, J.D. (author)
We report extensive measurements on a new compound (Yb0.24Sn0.76)Ru that crystallizes in the cubic CsCl structure. Valence-band photoemission (PES) and L3 x-ray absorption show no divalent component in the 4f configuration of Yb. Inelastic neutron scattering (INS) indicates that the eight-fold degenerate J-multiplet of Yb3+ is split by the...
journal article 2011
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Wang, X.S. (author), Yan, P. (author), Shen, Y.H. (author), Bauer, G.E.W. (author), Wang, X.R. (author)
We theoretically study field-induced domain wall motion in an electrically insulating ferromagnet with hard- and easy-axis anisotropies. Domain walls can propagate along a dissipationless wire through spin wave emission locked into the known soliton velocity at low fields. In the presence of damping, the usual Walker rigid-body propagation mode...
journal article 2012
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Wang, S.Z. (author), Xia, K. (author), Bauer, G.E.W. (author)
We compute the thermoelectric transport parameterized by the Seebeck coefficient and thermal/electric conductance of random-alloy FeCo/MgO/FeCo(001) magnetic tunnel junctions (MTJs) from first principles using a generalized Landauer-Büttiker formalism. The thermopower is found to be typically smaller than those of Fe/MgO/Fe(001) MTJs. The ...
journal article 2014
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Wang, Lu (author), Qin, Z. (author), Dong, J. (author), Bauer, P. (author)
In recent years, electrical vehicle (EV) starts showing its unique advantages that the conventional combustion vehicles do not have. Together with the increasing interests on EV, the motor drive with higher efficiency and lighter weight also becomes more attractive. A promising solution is to apply the wide band gap (WBG) components including...
conference paper 2019
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Wang, Hanchen (author), Chen, Jilei (author), Yu, T. (author), Liu, Chuanpu (author), Guo, Chenyang (author), Liu, Song (author), Shen, Ka (author), Jia, Hao (author), Bauer, G.E. (author)
Nanomagnets are widely used to store information in non-volatile spintronic devices. Spin waves can transfer information with low-power consumption as their propagations are independent of charge transport. However, to dynamically couple two distant nanomagnets via spin waves remains a major challenge for magnonics. Here we experimentally...
journal article 2020
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Beloqui Larumbe, L. (author), Qin, Z. (author), Wang, L. (author), Bauer, P. (author)
This article presents a small-signal model for power-electronics converters that use a typical control structure in wind energy applications: the double synchronous reference frame current control. The article considers the presence of unbalanced currents and voltages, and analyzes their impact on the frequency couplings of the converter. In...
journal article 2021
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Liao, Jianquan (author), Zhou, Niancheng (author), Qin, Z. (author), Purgat, P. (author), Wang, Qianggang (author), Bauer, P. (author)
The two main challenges of medium voltage direct current (MVDC) distribution network are the flexible control of power flow (PF) and fault protection. In this paper, the power flow controller (PFC) is introduced to regulate the PF and inhibit the fault current during the DC fault. The coordination strategy of series-parallel PFC (SP-PFC) and...
journal article 2021
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Wang, L. (author), Qin, Z. (author), Beloqui Larumbe, L. (author), Bauer, P. (author)
To accurately simulate electric vehicle DC fast chargers' (DCFCs') harmonic emission, a small time step, i.e., typically smaller than 10 μs, is required owing to switching dynamics. However, in practice, harmonics should be continuously assessed with a long duration, e.g., a day. A trade-off between accuracy and time efficiency thus exists. To...
journal article 2021
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Wang, L. (author), Qin, Z. (author), Slangen, T (author), Bauer, P. (author), van Wijk, T (author)
With growing concern on climate change, widespread adoption of electric vehicles (EVs) is important. One of the main barriers to EV acceptance is range anxiety, which can be alleviated by fast charging (FC). The main technology constraints for enabling FC consist of high-charging-rate batteries, high-power-charging infrastructure, and grid...
journal article 2021
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Wang, L. (author), Qin, Z. (author), Beloqui Larumbe, L. (author), Bauer, P. (author)
To accurately simulate the harmonic emission of EV DC fast chargers (DCFCs) and the harmonic voltage of the power grid to which the chargers are connected, a small time-step, i.e., typically smaller than 10μs, is required. However, for harmonic assessment, a long timescale, typically a day, is required. A conflict between accuracy and time...
conference paper 2021
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Xu, J. (author), Soeiro, Thiago B. (author), Wang, Yong (author), Gao, Fei (author), Tang, Houjun (author), Bauer, P. (author)
Two-stage AC-DC converters are considered as a prominent solution for DC-type electric vehicle (EV) chargers. However, this kind of architecture suffers from high switching losses with large heatsink and DC-link capacitor volume. To relieve this issue, this paper presents a new hybrid modulation for DC-type EV chargers, where a two-phase...
journal article 2022
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Xu, J. (author), Soeiro, Thiago B. (author), Wu, Y. (author), Gao, Fei (author), Wang, Y. (author), Tang, Houjun (author), Bauer, P. (author)
A three-phase buck-type rectifier features a step-down ac-dc conversion function, which is considered as a prominent solution for electric vehicle chargers and telecommunication systems integrated to the grid above 380 V line to line. However, traditional solutions for those applications employ cascaded architectures with an ac-dc boost-type...
journal article 2022
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Sun, S.Z. (author), Wang, Zhenpo (author), Liu, Peng (author), Qin, Z. (author), Chen, Yong (author), Han, Yang (author), Wang, Peng (author), Bauer, P. (author)
Battery fault diagnosis is crucial for stable, reliable, and safe operation of electric vehicles, especially the thermal runaway early warning. Developing methods for early failure detection and reducing safety risks from failing high energy lithium-ion batteries has become a major challenge for industry. In this article, a real-time early...
journal article 2022
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Xiao, J. (author), Wang, L. (author), Qin, Z. (author), Bauer, P. (author)
Smart grid steady control relies heavily on the communication infrastructure among sensors, actuators, and control systems, which makes it vulnerable to cyber-attacks. Accurate acquisition of dynamic state information is deemed vital for efficient detection of these cyber-attacks on a smart grid. However, several popular state estimation...
conference paper 2022
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Qin, Z. (author), Wang, L. (author), Bauer, P. (author)
Electric vehicles (EVs) are playing a crucial role in achieving the carbon neutral goal. To make the charging experience comparable with the refueling of the gasoline cars, more and more chargers are installed and connected to the grid. Meanwhile, the charging power is going up. As a result, more and more power quality issues associated with EV...
conference paper 2022
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Xiao, J. (author), Wang, L. (author), Qin, Z. (author), Bauer, P. (author)
Distributed secondary control is deemed necessary to restore the state of AC micro-grids to set points. However, for its limited global information, the power electronic system is vulnerable to cyber-attacks that aim to desynchronize converters or even cause a shutdown of micro-grids by unnecessarily triggering the protection schemes. To this...
conference paper 2022
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Liang, Y. (author), Wang, L. (author), Qin, Z. (author), Bauer, P. (author)
In emerging fast-charging stations, DC fast chargers (DCFCs) are employed which rely on power electronics and control to achieve the required performance. Harmonic emission induced by the complex system behavior is of great concern in the DCFC system. This paper proposes a harmonic emission model for the typical electric vehicle charger...
conference paper 2022
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Wang, L. (author), Qin, Z. (author), Bauer, P. (author)
Extracting an electric vehicle (EV) charger's input impedance with the analytical model (white-box approach) or the frequency sweep (black-box approach) is limited by the parameter confidentiality or the measurement noise, respectively. To overcome these challenges, a gradient-descent (GD) optimization-based gray-box modeling approach is...
journal article 2023
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