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Frequency-Coupled Impedance Modeling of Virtual Synchronous Generators
IEEE Transactions on Power Systems, 2021The impedance of the virtual synchronous generator (VSG) is an effective method to analyze the dynamic interactions between the VSG and the grid. For the existence of power controllers and asymmetric inner-loop controllers in the d- and q-axis, there are couplings in the output sequence impedance of VSG.
Kai Shi +4 more
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Modified Adaptive Virtual Impedance Method to Compensate Mismatched Line Impedances in Microgrids
2019 IEEE Applied Power Electronics Conference and Exposition (APEC), 2019Under mismatched line impedance conditions, reactive power sharing performance of droop control tends to be barely satisfactory for the absence of sharing accuracy. Therefore, to realize accurate reactive power sharing of parallel-connected inverters in microgrids, a modified adaptive virtual impedance method is proposed in this paper.
Ronghui AN, Zeng LIU, Jinjun LIU
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Virtual Biopsies in Barrett's Esophagus Using an Impedance Probe
Annals of the New York Academy of Sciences, 1999Abstract: Preliminary results of electrical impedance measurements in squamous and columnar epithelia in rat and human tissues are presented. The aim of this work is to show the possibility of differentiating these two types of epithelia in terms of their electrical characteristics. For the measurements, we employed a 1.95m‐long, 3.2‐mm‐diameter, four‐
C A, González-Correa +8 more
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Parameter Optimization of Virtual Impedance for Parallel Inverter
Advanced Materials Research, 2014This paper deals with parameter optimization of virtual impedance of parallel inverter. Conventional design methods determine parameters by observing the changes of amplitude-frequency and phase frequency curves of the equivalent impedance. However, those methods always neglect the dynamic performance of inverters in parallel.
Ping Wang, Liu Yang
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Virtual Impedance Control for Safe Human-Robot Interaction
Journal of Intelligent & Robotic Systems, 2015Collision avoidance is essential for safe robot manipulation. Especially with humans around, robots should work only when safety can be robustly guaranteed. In this paper, we propose using virtual impedance control for reactive, smooth, and consistent collision avoidance that interferes minimally with the original task.
Sheng-Yen Lo +2 more
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Virtual impedance attenuation based control of parallel inverters
2014 IEEE Conference and Expo Transportation Electrification Asia-Pacific (ITEC Asia-Pacific), 2014Current sharing is a main problem in AC power supply system with multiple inverters parallel connected. Some methods are developed to eliminate the loop-current among inverters including droop control and virtual impedance. However, big voltage drop is inevitable for a good current sharing.
null Ningning Li +4 more
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Collision Avoidance Among Multiple Robots Using Virtual Impedance
Proceedings. IEEE/RSJ International Workshop on Intelligent Robots and Systems '. (IROS '89) 'The Autonomous Mobile Robots and Its Applications, 2005path planning. The higher layei generates a trajectory from the current position to the goal. 'The lower layer controls the servo driver to follow the generated trajectory while avriidinp, obstaclcs. This laycr is composcd of thrce modules called "watchdog", 'navigator*. and "deadlock solver".
T. Arai, H. Ogata, T. Suzuki
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Fuzzy virtual impedance controller in human-vehicle interaction
2009 IEEE International Conference on Systems, Man and Cybernetics, 2009In the previous studies mechanical impedance has become well implement in the field of human-machine interaction. However, in human-vehicle interaction there is a variant environment when driving a vehicle, thus apart from interacting with human, impedance controller is needed to adapt to the variant environment. But for mechanical impedance as being a
Shenghao Zhou, Seiji Yasunobu
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An improved droop control with tunable virtual impedance
2016 Chinese Control and Decision Conference (CCDC), 2016A droop control with tunable virtual impedance based on the cloud model theory is proposed in the paper. Because of the imbalance feeder impedance in low voltage micro-grid, it is difficult for the traditional droop control to get good performance. The tunable virtual impedance is needed to conquer these problems due to the difficulty of getting the ...
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Virtual Tumor Board: Papillary thyroid carcinoma with nodal disease
Ca-A Cancer Journal for Clinicians, 2023Peter J Abraham
exaly