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An Improved Fast Distance Relay to Mitigate the Impacts of Rogowski Coil Transducer Transient

IEEE TRANSACTIONS ON POWER DELIVERY 2022年第3期37卷 1549-1558页

作者： Li, Baowei Wen, Minghao Shi, Xin Wang, Li Chen, Yu Huazhong Univ Sci & Technol Hubei Elect Power Secur & High Efficiency Key Lab State Key Lab Adv Electromagnet Engn & Technol Wuhan 430074 Peoples R China Xj Elect Co Ltd Xuchang 461000 Henan Peoples R China

The Rogowski coil transducer's integrator will amplify the transmission error, which may lead to mal-operation of the relay. In this paper, a novel method of line relay based on the differential output of Rogowski coil is proposed. Besides, an improved fast distance relay based on the differential output of Rogowski coil is presented. Based on the equal transfer process of transmission lines(ETPTL), the voltage signal should be processed by the virtual Rogowski coil to solve the inconsistent transfer problem between voltage and current. Furthermore, this paper also presents the reconstruction method of voltage at the fault point and the least-square algorithm to solve the R-L differential equation, so as to improve the algorithm accuracy. Furthermore, the equal transfer process error of the virtual Rogowski coil is analyzed in the paper, and the design principle of low pass filter is also proposed. Simulation results and experiment results demonstrate that the improved fast distance relay scheme has high operation speed, which is signed prior to other distance relay schemes. The proposed method also provides a valuable reference for other types of transmission line relay based on Rogowski coil transducer.

关键词： Protective relaying Transient analysis Voltage measurement Transmission line measurements Transducers Mathematical model Equivalent circuits Rogowski coil integrator distance relay virtual type of rogowski coil fault location voltage reconstruction least-square algorithm

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Stability and Optimality of Non-cooperative Stochastic Adaptive Games with Different Estimations 41

Stability and Optimality of Non-cooperative Stochastic Adapt...

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第41届中国控制会议

作者： Haoyang Hu Yantai University School of Mathematics and Information Sciences

ISBN: (数字)9789887581536

ISBN: (纸本)9781665482561

We consider non-cooperative stochastic adaptive games described by a linear discrete-time stochastic system with two *** the system parameters are unknown,we assume that the players apply the least-square algorithm to estimate the unknowns respectively instead of using the same *** to "certainty equivalence principle",the players need to design adaptive strategy profile to optimize their one-step-ahead payoff *** will show that the resulting adaptive strategy profile can make the closed-loop system globally stable and in some sense,the profile is an asymptotic Nash equilibrium.

关键词： Stochastic Adaptive Games least-square algorithm Globally Stable Asymptotic Nash Equilibrium

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Online identification method for a system with unknown varying time-delay and parameter

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TRANSACTIONS OF THE INSTITUTE OF MEASUREMENT AND CONTROL 2021年第14期43卷 3267-3271页

作者： Hu, Yifei Wu, Jinbo Huazhong Univ Sci & Technol Sch Naval Architecture & Ocean Engn Luoyu Rd 1037 Wuhan 430074 Peoples R China Hubei Key Lab Naval Architecture & Ocean Engn Hyd Wuhan Peoples R China

An online identification method that can simultaneously estimate the unknown system parameter and the unknown time-delay is proposed. Firstly, with the help of Lagrange mean value theorem, the system with time-delay can be transformed into two terms that can be identified by modified least-square algorithm and one term that represents an approximate error. Then, a modified least-square algorithm is introduced to estimate all the unknown parameters in case of external disturbances. Additionally, an restrain term are added in the covariance matrix to enhance the robustness to deal with the approximate error which is related to the estimated error of system parameter and time-delay. Also, the boundedness of the estimation error is guaranteed via Lyapunov stability theory. Finally, the effectivity of the proposed method is verified by simulations results.

关键词： Parameter estimation varying time-delay least-square algorithm

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Parameter Extraction of An Ultracapacitor's Equivalent Circuit Model Using a Genetic algorithm Approach 10

Parameter Extraction of An Ultracapacitor's Equivalent Circu...

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10th IEEE Annual Energy Conversion Congress and Exposition (ECCE)

作者： Chen, Xi Pise, Anirudh Hussein, Ala Batarseh, Issa Univ Cent Florida Florida Power Elect Ctr Dept Elect & Comp Engn Orlando FL 32816 USA Yarmouk Univ Dept Elect Power Engn Irbid Jordan

ISBN: (纸本)9781479973125

This paper proposes a new method for extracting some equivalent-circuit model parameters of an ultracapacitor using Genetic algorithm (GA) approach. Ultracapacitors have two main parameters that dictates their performance: internal resistance and the capacitance. These parameters change drastically with temperature variations and age conditions. These parameters also vary from an ultracapacitor to another even if they were from the same manufacturer due to the manufacturing process. Hence, in order to allow accurate prediction of the ultracapacitor performance, an accurate value of these parameters is vital. The proposed algorithm is presented in this paper followed by experimental verification using a BCAP3000 2.7V, 3000F Maxwell ultracapacitor. The accuracy of the algorithm is evaluated and compared to the traditional least-square algorithm (LSA).

关键词： ultracapacitor parameter extraction genetic algorithm least-square algorithm

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Enhanced high dynamic range 3D shape measurement based on generalized phase-shifting algorithm

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OPTICS COMMUNICATIONS 2017年 385卷 43-53页

作者： Wang, Minmin Du, Guangliang Zhou, Canlin Zhang, Chaorui Si, Shuchun Li, Hui Lei, Zhenkun Li, YanJie Shandong Univ Sch Phys Jinan 250100 Peoples R China Dalian Univ Technol Dept Engn Mech Dalian 116024 Peoples R China Jinan Univ Sch Civil Engn & Architecture Jinan 2250020 Peoples R China

Measuring objects with large reflectivity variations across their surface is one of the open challenges in phase measurement profilometry (PMP). Saturated or dark pixels in the deformed fringe patterns captured by the camera will lead to phase fluctuations and errors. Jiang et al. proposed a high dynamic range real-time three-dimensional (3D) shape measurement method (Jiang et al., 2016) [17] that does not require changing camera exposures. Three inverted phase-shifted fringe patterns are used to complement three regular phase-shifted fringe patterns for phase retrieval whenever any of the regular fringe patterns are saturated. Nonetheless, Jiang's method has some drawbacks: (1) the phases of saturated pixels are estimated by different formulas on a case by case basis;in other words, the method lacks a universal formula;(2) it cannot be extended to the four step phase-shifting algorithm, because inverted fringe patterns are the repetition of regular fringe patterns;(3) for every pixel in the fringe patterns, only three unsaturated intensity values can be chosen for phase demodulation, leaving the other unsaturated ones idle. We propose a method to enhance high dynamic range 3D shape measurement based on a generalized phase-shifting algorithm, which combines the complementary techniques of inverted and regular fringe patterns with a generalized phase-shifting algorithm. Firstly, two sets of complementary phase-shifted fringe patterns, namely the regular and the inverted fringe patterns, are projected and collected. Then, all unsaturated intensity values at the same camera pixel from two sets of fringe patterns are selected and employed to retrieve the phase using a generalized phase-shifting algorithm. Finally, simulations and experiments are conducted to prove the validity of the proposed method. The results are analyzed and compared with those of Jiang's method, demonstrating that our method not only expands the scope of Jiang's method, but also improves measuremen

关键词： Phase-shifting algorithm High dynamic range (HDR) Phase measuring profilometry (PMP) Fringe projection least-square algorithm Phase error

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Enhanced two-frequency phase-shifting method based on generalized phase-shifting algorithm

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JOURNAL OF MODERN OPTICS 2017年第16期64卷 1614-1625页

作者： Wang, Minmin Du, Guangliang Zhou, Canlin Si, Shuchun Li, XiaoLei Lei, Zhenkun Li, YanJie Shandong Univ Sch Phys Jinan Peoples R China Hebei Univ Technol Sch Mech Engn Tianjin Peoples R China Dalian Univ Technol Dept Engn Mech Dalian Peoples R China Jinan Univ Sch Civil Engn & Architecture Jinan Peoples R China

In this paper, we develop a novel dual-frequency pattern which not only releases the restriction of conventional two-frequency phase-shifting algorithm that at least six fringe patterns are needed, but reduces the noise impact by decreasing the frequency ratio between the high- and low-components. To decrease the number of necessary patterns to five, a novel composite dual-frequency pattern scheme combining together a high- with a low-frequency pattern is employed. To make the algorithm less sensitivity to noise, the low-frequency component is with more than one period fringes, which is relatively prone to recover the continuous result by simple spatial phase unwrapping approach. Besides, the restriction of special phase shifts between two-frequency components in conventional methods is released by the generalized phase-shifting algorithm. Simulations and experiments are conducted to demonstrate that in addition to maintaining the minimum number of patterns, the proposed method reveals higher accuracy of phase retrieval.

关键词： Two-frequency phase-shifting algorithm phase measuring profilometry fringe projection least-square algorithm phase error

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A Generic Electrothermal Li-ion Battery Model for Rapid Evaluation of Cell Temperature Temporal Evolution

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IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS 2017年第2期64卷 998-1008页

作者： Motapon, Souleman Njoya Lupien-Bedard, Alexandre Dessaint, Louis-A. Fortin-Blanchette, Handy Al-Haddad, Kamal Univ Quebec Ecole Technol Super Grp Rech Elect Puissance & Commande Ind Montreal PQ H3C 1K3 Canada

This paper presents a generic electrothermal model for Li-ion battery. The model is developed with the objective to simplify the parameter identification procedure, while representing adequately the thermal effects on the battery performance. Most of the well-accepted electrothermal Li-ion battery models require in-depth and proprietary battery data or dedicated test environments for parameter identification. The dedicated test bench usually involves expensive thermal test chambers, calorimeters, and temperatures sensors, and challenges associated with their installations. This makes the electrical and thermal simulation of Li-ion batteries difficult to achieve. This paper proposes a generic electrothermal model with a simpler parameter identification process. The parameters identification process is solely based on datasheet discharge curves and simple experiments at room temperature. The model is validated experimentally using a 12 V 40 Ah LiFePO4 battery module. The performance of the model is tested with constant current discharges, constant current-constant voltage charges, as well as with a Simplified Federal Urban Driving Schedule dynamic driving cycle, at different operating temperatures. As expected, the simulation results show an error within +/- 1% and +/- 1.3% compared to experimental results, for both steady and dynamic states, respectively.

关键词： Charging constant current-constant voltage (CC-CV) electrical simulation electrothermal modeling generic battery model least-square algorithm Li-ion batteries

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Gas storage valuation with regime switching

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ENERGY SYSTEMS-OPTIMIZATION MODELING SIMULATION AND ECONOMIC ASPECTS 2016年第3期7卷 499-528页

作者： Baeuerle, Nicole Riess, Viola Karlsruhe Inst Technol Dept Math D-76128 Karlsruhe Germany

In this paper we treat a gas storage valuation problem as a Markov Decision Process. As opposed to existing literature we model the gas price process as a regime-switching model. Such a model has shown to fit market data quite well in Chen and Forsyth (Quant Finance 10:159-176, 2010). Before we apply a numerical algorithm to solve the problem, we first identify the structure of the optimal injection and withdrawal policy. This part extends results in Secomandi (Manag Sci 56:449-467, 2010). Knowing the structure reduces the complexity of the involved recursion in the algorithms. We explain the usage and implementation of two algorithms: a Multinomial-Tree algorithm and a least-square Monte Carlo algorithm. Both algorithms are shown to work for the regime-switching extension. In a numerical study we compare these two algorithms.

关键词： Gas storage valuation Regime switching Markov Decision Process least-square algorithm Multinomial-Tree algorithm

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Delta Carrier Range algorithm for Indoor Positioning Application to Pseudolite-like Transmitters

Delta Carrier Range Algorithm for Indoor Positioning Applica...

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International Conference on Indoor Positioning and Indoor Navigation (IPIN)

作者： Alexandre, Vervisch-Picois Nel, Samama Univ Paris Saclay CNRS Telecom SudParis Lab SAMOVAR Evry France

ISBN: (纸本)9781509024254

Indoor positioning with Pseudolites consists of deploying a network of terrestrial transmitters which have the same function as the Global Navigation Satellite Systems (GNSS) outdoor. In this paper, we propose an algorithm that allows carrying out sub-metric positioning using precise carrier phase measurements for a dynamic receiver. During the motion, the measured carried phases are changing according to relative position between the receiver and the transmitters. With enough transmitters, typically 4 for 2D positioning, and unless 3 measurements for each transmitters, it is thus possible to calculate the initial position of the motion. The algorithm and its limitations are explained. Finally, experimental results are presented to validate the previously presented concepts.

关键词： Indoor Positioning Pseudolite least-square algorithm Dilution of Precision Carrier Phase

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Comparison of two different (quasi-) dynamic testing methods for the performance evaluation of a Linear Fresnel Process Heat Collector

Comparison of two different (quasi-) dynamic testing methods...

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International Conference on Concentrating Solar Power and Chemical Energy Systems (SolarPACES)

作者： Hofer, A. Buechner, D. Kramer, K. Fahr, S. Heimsath, A. Platzer, W. J. Scholl, S. Fraunhofer Inst Solar Energy Syst ISE D-79110 Freiburg Germany Tech Univ Carolo Wilhelmina Braunschweig Inst Chem & Thermal Proc Engn ICTV D-38106 Braunschweig Germany

A small-scale Linear Fresnel Collector (LFC) for the generation of process heat has been tested by Fraunhofer ISE;its performance was evaluated by means of two different methods. The first is a quasi-dynamic testing method performed according to the testing standard ISO 9806: 2013, with modifications in the model to accurately describe LFCs. Due to the two-dimensional Incidence Angle Modifier (IAM) of an LFC, an iterative multi-linear regression (MLR) approach has been developed to be able to comprehensively evaluate the optical performance. The second method is a dynamic testing method based on a parameter identification incorporating a multi-node/plug-flow collector model without strict restraints on mass flow and inlet temperature stability. Both methods are briefly described in their conceptual design and their basic requirements, revealing their similarities and differences. Each method is then applied to real measurement data from an LFC, assessing practicability and identification accuracy. For both methods, the mean absolute difference between identified IAM values and results from ray tracing fell in a range of 0.013-0.017, leading to a similar accuracy in LFC performance evaluation. Differences in optical efficiency between the two methods are smaller, with an average absolute difference below 0.0098, even when using different measurement data and simulation models. Thus the dynamic method represents a good starting point for the further development of an alternative dynamic testing and evaluation method with more flexibility than the current testing standard. This will be significant when evaluating large-scale concentrating collectors and collectors with direct steam generation. (C) 2015 The Authors. Published by Elsevier Ltd.

关键词： Linear Fresnel collector performance evaluation parameter indentification method process heat collector multi-linear regression least-square algorithm

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