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arxiveess.SY2026-07-07

Understanding Small-Signal Impedance Matrices in Different Reference Frames

J. Pedra

This paper systematically analyzes the relationships among the $dq$-domain, $αβ$-domain, and sequence-domain representations used in small-signal impedance modeling of voltage-source converters (VSCs). It is shown that the AC impedance matrix expressed with $dq$-complex and $αβ$-complex variables leads to different formulations in the sequence domain. The study demonstrates that asymmetric systems exhibit different physical phenomena in the rotating and stationary reference frames; therefore, the transformations between these frames are not physically consistent in such cases. It is also demonstrated that the so-called modified sequence-domain impedance is equivalent to the universal impedance model in the frequency domain. The analysis clarifies several notational inconsistencies found in the literature. Finally, a physical interpretation is presented highlighting the implications of using stationary and rotating reference frames for stability analysis of power converters.

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arxiveess.SY2026-07-18

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arxiveess.SY2026-07-14

Stability Analysis of Grid-Following and Grid-Forming Converters Connected to Generators

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arxiveess.SPeess.SY2026-07-12

Fuse-then-Detect for Passive UAV Localization Using Multi-UE 5G Uplink Signals

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arxiveess.SYcond-mat.mtrl-sci2026-07-20

Multisine electrochemical impedance spectroscopy for Li-ion battery characterisation

Noël Hallemans, Heiko Seel-Mayer, Peter Keil, Stephen R. Duncan, David A. Howey

Electrochemical impedance spectroscopy (EIS) is a valuable tool for non-invasive battery characterisation as it provides a compact data representation of physical processes over a wide range of time scales. Commonly, sinusoids at different frequencies are injected sequentially (s…

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arxivcs.CVeess.SY2026-07-17

CLIFE: Camera-LiDAR Fusion Framework for Edge-Deployable Roadside VRU Perception

Tam Bang, Hoang H. Nguyen, Lei Cheng, Lihao Guo, Siyang Cao, Hussam Abubakr, et al.

Reliable roadside perception of vulnerable road users (VRUs) remains challenging under occlusions, variable lighting, and diverse weather conditions, particularly under strict edge-computing and latency constraints. Existing multi-sensor fusion systems rely on cloud or server-gra…

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