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IET International Conference on Developments in Power System Protection

作者： J. L. Suonan C. Q. Wang Z. B. Jiao School of Electrical Engineering Xi'an Jiaotong University

ISBN: (纸本)9781622761050

This paper proposes a novel transmission line protection scheme based on frequency-domain model identification method with distributed parameter. Integrated impedance is defined by voltages and currents of two end terminals of transmission line. By analyzing the frequency-domain expressions of integrated impedance in internal and external fault states, the amplitude-frequency characteristics of the integrated impedance are discussed. The integrated impedance in internal fault state shows system impedance characteristic and the integrated impedance in external fault state shows the line distributed capacitive characteristic. The frequency-domain model errors are defined as unbalanced currents respectively in order to identify the internal and external faults. Matrix pencil algorithm is used to calculate the phasors in different frequencies in the proposed scheme. Protection criterions are designed and some tests are performed. The simulation results show that the proposed schemes can detect internal fault quickly and reliably. Furthermore, the influences from capacitive currents and transition resistances can be avoided in the proposed protection scheme.

关键词： distributed parameter Frequency-domain model identification Pilot protection Integrated impedance Matrix pencil algorithm

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Analysis and design of high-performance liquid crystal phase shifter based on nanowire filled membrane and spoof surface plasmon polaritons

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MICROELECTRONICS JOURNAL 2025年 158卷

作者： Wang, Haoyuan Meng, Fanyi Tu, Lei Liu, Rong Zheng, Zijun Wang, Yuxin Ding, Chang Liu, Ruizhi Harbin Inst Technol Dept Microwave Engn Harbin Peoples R China Harbin First Hosp Emergency Dept Harbin 150010 Peoples R China Air Force Engn Univ Shaanxi Key Lab Artificially Struct Funct Mat & De Xian Peoples R China Harbin Engn Univ Coll Informat & Commun Engn Harbin Peoples R China

In this paper, the design and analysis methods of Liquid crylstal phase shifter (LCPS) with high performance based on nanowire filled membrane (NaM) and spoof surface plasmon polariton (SSPP) are proposed. The equivalent transmission line model and distributed circuit parameters of a NaM-LCPS are constructed and compared with those of a conventional microstrip line liquid crystal phase shifter (ML-LCPS) to reveal the causes of the high figure of merit (FoM) of the NaM-LCPS. Building upon above analyses, an idea of combination of SSPP and NaM-LCPS is proposed to improve the NaM-LCPS's performance. Simulation results show that the NaMSSPP-LCPS reaches an outstanding FoM of 123.5 degrees/dB and a per wavelength phase shift of 377.5 degrees/lambda 0, however, NaM-LCPS only has a FoM of 98.9 degrees/dB and a phase shift of 241 degrees/lambda 0 per wavelength, which increases by 24.87 % and 56.64 % compared to the NaM-LCPS, respectively, implying higher efficiency and more compact physical size.

关键词： Liquid crystal (LC) Nanowire filled membrane Phase shifter distributed parameter Spoof surface plasmon polaritons

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Robust sensor scheduling via iterative design for parameter estimation of distributed systems 19

Robust sensor scheduling via iterative design for parameter ...

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19th International Conference on Methods and Models in Automation and Robotics (MMAR)

作者： Patan, Maciej Kowalow, Damian Univ Zielona Gora Zielona Gora Poland

ISBN: (纸本)9781479950812

The problem of selection of measurement data provided by sensor array so as to maximize the accuracy of parameter estimation of a distributed system defined in a given multidimensional domain is discussed. Usually, when designing an identification experiment for nonlinear models, the uncertainty of nominal parameters has to be taken into account. In particular, an iterative scheme for parameter estimation is proposed enhanced with sequential experimental design techniques where there is no particular information about the parameter distribution. The setting examined here correspond to situation where from among the observations provided by nodes of given sensor array the most informative measurements have to be selected in order to provide an update of the parameter estimates. Finally, a proposed approach is verified by a computer simulation regarding heat transfer problem.

关键词： design of experiments distributed processing iterative methods parameter estimation sensor fusion computer simulation distributed systems heat transfer problem iterative design multidimensional domain nominal parameters nonlinear models parameter distribution robust sensor scheduling sensor array sequential experimental design techniques Arrays Estimation Face Noise measurement Schedules Temperature measurement Time measurement parameter estimation distributed Systems Sensor arrays time measurement Nonlinear Models Noise measurement distributed processing Sensor fusion temperature measurement Computer Simulation iterative methods Experimental Design Face Face distributed parameter

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Estimation with Heisenberg-Scaling Sensitivity of a Single parameter distributed in an Arbitrary Linear Optical Network

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SENSORS 2022年第7期22卷 2657页

作者： Triggiani, Danilo Tamma, Vincenzo Univ Portsmouth Sch Math & Phys Portsmouth PO1 3QL Hants England Univ Portsmouth Inst Cosmol & Gravitat Portsmouth PO1 3FX Hants England

Quantum sensing and quantum metrology propose schemes for the estimation of physical properties, such as lengths, time intervals, and temperatures, achieving enhanced levels of precision beyond the possibilities of classical strategies. However, such an enhanced sensitivity usually comes at a price: the use of probes in highly fragile states, the need to adaptively optimise the estimation schemes to the value of the unknown property we want to estimate, and the limited working range, are some examples of challenges which prevent quantum sensing protocols to be practical for applications. This work reviews two feasible estimation schemes which address these challenges, employing easily realisable resources, i.e., squeezed light, and achieve the desired quantum enhancement of the precision, namely the Heisenberg-scaling sensitivity. In more detail, it is here shown how to overcome, in the estimation of any parameter affecting in a distributed manner multiple components of an arbitrary M-channel linear optical network, the need to iteratively optimise the network. In particular, we show that this is possible with a single-step adaptation of the network based only on a prior knowledge of the parameter achievable through a "classical" shot-noise limited estimation strategy. Furthermore, homodyne measurements with only one detector allow us to achieve Heisenberg-limited estimation of the parameter. We further demonstrate that one can avoid the use of any auxiliary network at the price of simultaneously employing multiple detectors.

关键词： quantum metrology quantum sensing distributed parameter heisenberg limit gaussian metrology squeezing

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Enhancing the precision of impedance measurement from 5 kHz to 1 MHz through self-identification of parasitic parameters

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PHYSIOLOGICAL MEASUREMENT 2025年第3期46卷 2025 Feb 24页

作者： She, Yi Jiang, Zeyi Liu, Qin Qiao, Sirui Ma, Yixin Shanghai Jiao Tong Univ Sch Elect Informat & Elect Engn Shanghai 200240 Peoples R China

Objective. Electrical impedance tomography (EIT) generates cross-sectional images through non-invasive impedance measurements from surface electrodes. While impedance above 200 kHz can reveal intracellular properties, most existing EIT images are published at frequencies below 200 kHz. When frequencies exceed 200 kHz, the accuracy of impedance measurements declines due to the distributed circuit parameters such as parasitic capacitance, on-resistance of switch and the series inductance, with a more significant impact on larger impedance. To overcome this limitation, this paper proposes an approach to enhance the precision of impedance measurement through self-identification of distributed parameter. Approach. Firstly, the distributed circuit parameters are identified via correction measurements of precision resistances in the frequency range from 5 kHz to 1 MHz;then, the circuit is accurately modeled;finally, transfer impedance measurements during imaging process are corrected using the established circuit model. Main results. The distributed circuit parameter self-identification method was verified through a goodness-of-fit test, confirming the consistency between the model's predicted values and the actual values of the component. The test results indicate that at 1 MHz, the relative residuals follow a right-skewed distribution with an average value of 0.08%, which demonstrates high model accuracy. At 1 MHz, the relative error after correction for the 499 Omega precision resistor measurement is reduced by 12.01%, and for the 56 pF precision capacitor in parallel with 249 Omega, the relative error after correction is 0.46%. Significance. The proposed method can extend the frequency range of EIT and other impedance technologies from below 200 kHz to up to 1 MHz, while ensuring good measurement accuracy.

关键词： electrical impedance tomography distributed parameter precision of impedance measurement multi-frequency EIT

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Open-loop implementation of feedbacks in parametric optimization problems for incompletely determined systems with distributed parameters

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JOURNAL OF COMPUTER AND SYSTEMS SCIENCES INTERNATIONAL 2016年第3期55卷 365-379页

作者： Rapoport, E. Ya. Samara State Tech Univ Ul Molodogvardeiskaya 244 Samara 443100 Russia

A constructive method for the design and real-time implementation of parameterized open-loop controls in the optimal feedback control of ensembles of trajectories of incompletely determined parabolic systems with distributed parameters is proposed. This method uses reduction to semiinfinite optimization problems, alternance properties of their solutions, and additional information about fundamental laws of the application domain. The practical application of the results is illustrated by the example of controlling nonstationary temperature fields under multiple disturbances, which is a problem of independent interest.

关键词： Parametric trajectory Feedback optimal feedback control distributed parameter Temperature fields Ensembles extra message

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Open-loop controllability of multidimensional linear systems with distributed parameters

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JOURNAL OF COMPUTER AND SYSTEMS SCIENCES INTERNATIONAL 2015年第2期54卷 184-201页

作者： Rapoport, E. Ya Samara State Tech Univ Samara 443100 Russia

The problem of controllability of linear multidimensional models of dynamical systems with distributed parameters is considered for a given set of open-loop trajectories that transfer the plant into the terminal state. Based on the behavior of these trajectories in the spatial and temporal domain, we obtain necessary and sufficient conditions (that can be directly checked) for the existence of various technologically feasible controls ensuring that the necessary requirements are met. Using the methods proposed in this study, we give examples (which are of independent interest) for estimating the open-loop controllability of nonstationary heat conduction processes.

关键词： DYNAMICAL SYSTEMS Sufficient conditions MULTIDIMENSIONAL Necessary controllability Conductive heat transfer trajectory distributed parameter terminal states Linear system

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Harmonic Amplification Analysis of Cable Lines with distributed parameters Based on Kalman Filter and Convolution Inversion

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Journal of Modern Power Systems and Clean Energy 2023年第6期11卷 1804-1813页

作者： Yang Pu Qin Shu Fangwei Xu College of Electrical Engineering Sichuan UniversityChengdu 610065China IEEE

Harmonic amplification phenomena could appear at the point of common connection(PCC) of the cable line terminal. However, the distributed parameter model of the cable line contains hyperbolic functions with plural variables, which makes it challenging to obtain the harmonic amplification factor(HAF). Hence, a time-domain method combining the Kalman filter and convolution inversion(KFCI) methods is proposed to address this problem. First, the Kalman filter method optimizes the square wave pulse response(SWPR) with measurement error. Then, the optimized SWPR data are used to get the HAF by the convolution inversion method. Next, the harmonic amplification characteristics of cable lines are explored. Finally, an experimental simulation model is built on the PSCAD software, verifying the optimization effectiveness of Kalman filter for the SWPR with error and the accuracy of the HAF calculated by the proposed method. The analysis rationality of harmonic amplification properties is also demonstrated.

关键词： Cable line distributed parameter Kalman filter convolution inversion harmonic amplification

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Simplified distributed parameters BWR dynamic model for transient and stability analysis

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ANNALS OF NUCLEAR ENERGY 2006年第14-15期33卷 1245-1259页

作者： Espinosa-Paredes, Gilberto Nunez-Carrera, Alejandro Vazquez-Rodriguez, Alejandro Univ Autonoma Metropolitana Iztapalapa Area Ingn Recursos Engn Mexico City 09340 DF Mexico Comis Nacl Seguridad Nucl & Slavaguardias Mexico City 03020 DF Mexico

This paper describes a simplified model to perform transient and linear stability analysis for a typical boiling water reactor (BWR). The simplified transient model was based in lumped and distributed parameters approximations, which includes vessel dome and the downcomer, recirculation loops, neutron process, fuel pin temperature distribution, lower and upper plenums reactor core and pressure and level controls. The stability was determined by studying the linearized versions of the equations representing the BWR system in the frequency domain. Numerical examples are used to illustrate the wide application of the simplified BWR model. We concluded that this simplified model describes properly the dynamic of a BWR and can be used for safety analysis or as a first approach in the design of an advanced BWR. (c) 2006 Elsevier Ltd. All rights reserved.

关键词： Stability analysis Safety Analysis distributed parameter boiling water reactors

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Minimax optimization of stationary states in systems with distributed parameters

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JOURNAL OF COMPUTER AND SYSTEMS SCIENCES INTERNATIONAL 2013年第2期52卷 165-179页

作者： Rapoport, E. Ya Samara State Tech Univ Samara 443100 Russia

The minimization problem for deviations of the stationary state of a system with distributed parameters from a desired state estimated in the uniform metric is considered. A constructive method for its solution using a successive parameterization of controls and the alternance properties of optimal spatial distributions of the controlled variable is proposed. Examples of the use of the proposed computational scheme of the organization of computational algorithms in optimization problems of stationary thermal conductivity processes are discussed.

关键词： Optimization Stationary States distributed parameters control variable Stationary state Minimax system parameter optical coherence tomography angiography device distributed parameter

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