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Multi-time scale identification of key kinetic processes for lithium-ion batteries considering variable characteristic frequency

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Journal of Energy Chemistry 2023年第7期82卷 521-536,I0011页

作者： Haotian Shi Shunli Wang Jianhong Liang Paul Takyi-Aninakwa Xiao Yang Carlos Fernandez Liping Wang School of Information Engineering Southwest University of Science and TechnologyMianyang 621010SichuanChina Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China School of Pharmacy and Life Sciences Robert Gordon UniversityAberdeen AB10-7GJUK

The electrification of vehicles puts forward higher requirements for the power management efficiency of integrated battery management systems as the primary or sole energy *** this paper,an efficient adaptive multi-time scale identification strategy is proposed to achieve high-fidelity modeling of complex kinetic processes inside the *** specifically,a second-order equivalent circuit model network considering variable characteristic frequency is constructed based on the high-frequency,medium-high-frequency,and low-frequency characteristics of the key kinetic ***,two coupled sub-filters are developed based on forgetting factor recursive least squares and extended Kalman filtering methods and decoupled by the corresponding time-scale *** coupled iterative calculation of the two sub-filter modules at different time scales is realized by the voltage response of the kinetic diffusion *** addition,the driver of the low-frequency subalgorithm with the state of charge variation amount as the kernel is designed to realize the adaptive identification of the kinetic diffusion process ***,the concept of dynamical parameter entropy is introduced and advocated to verify the physical meaning of the kinetic *** experimental results under three operating conditions show that the mean absolute error and root-mean-square error metrics of the proposed strategy for voltage tracking can be limited to 13 and 16 mV,***,from the entropy calculation results,the proposed method can reduce the dispersion of parameter identification results by a maximum of 40.72%and 70.05%,respectively,compared with the traditional fixed characteristic frequency *** proposed method paves the way for the subsequent development of adaptive state estimators and efficient embedded applications.

关键词： Lithium-ion battery Kinetic parameters Entropy evaluation Parameter identification frequency characteristic

RESEARCH OF BJMOSFET frequency characteristicS

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Journal of Electronics(China) 2006年第4期23卷 590-593页

作者： Zeng Yun Yang Hongguan Shang Yuquan Li Xiaolei Zhang Yan Wu Yonghui Microelectronic Institute Hunan University Changsha 410082 China College of Electronic Info. ＆ Automation Tianjin Univ. of Science ＆ Tech. Tianjin 300222 China

The parasitic capacitance effect and its influence to the performance have been investigated in Bi-polar Junction Metal-Oxide-Semiconductor Field-Effect Transistor (BJMOSFET). The frequency characteristic equivalent circuit and high frequency response model of BJMOSFET have been presented. The frequency characteristic of BJMOSFET is simulated using the multi-transient analytical method and PSPICE9 simulator. The conclusions that BJMOSFET owns less total capacitance, wider frequency band, better transient charac-teristic and better frequency responses are reached by comparing with the traditional MOSFET at the same structure parameters and bias conditions. BJMOSFET, as a novel promising high frequency device, would be desired to find application in future integrated circuit.

关键词： Bipolar Junction Metal-Oxide-Semiconductor Field-Effect Transistor (BJMOSFET) frequency characteristic High frequency device PSPICE

Data-Driven Wind Turbine Wake Decomposition and Evolution Analysis: A frequency characteristics-based Clustering Procedure

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Data-Driven Wind Turbine Wake Decomposition and Evolution An...

An Infinite Horizon Linear Quadratic Problem with Unbounded Controls in Hilbert Space

第40届中国控制会议

作者： Zhenyu Chen Zhongwei Lin Jizhen Liu Gengda Li Feng Hu State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources School of Control and Computer Engineering North China Electric Power University Guodian New Energy Technology Research Institute Co. Ltd.

With the research in wind turbine wake deepening, frequency characteristics are gaining more attention. Data-driven methods are usually adopted to analyze the wake performance. In this paper, a frequency characteristics-based clustering procedure is proposed to decompose the wind turbine wake into clusters, of which the wake frequency-domain performance and dynamic wake evolution process can be analyzed. The proposed procedure first calculates the frequency amplitudes of the measured velocity time-series on every measurement point in space, then decomposes the wake according to the amplitudes using a clustering algorithm. Take the centroid in each cluster as an example, dominant frequency characteristics are analyzed, which show the wake meandering frequency while help the understanding of the dynamic wake evolution.

关键词： Data-Driven frequency characteristic Clustering Decomposition Dynamic Wake

来源： cnki会议评论

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Acta Mathematica Sinica,English Series 2001年第3期17卷 527-540页

作者： Han Zhong WU Xun Jing LI Department of Mathematics,Fudan University,Shanghai 200433,P.R.China E-mail:hzwu@*** xjli@*** Department of Mathematics Fudan University Shanghai 200433 P. R. China

An infinite horizon linear quadratic optimal control problem for analytic semigroup with unbounded control in Hilbert space is *** state weight operator is allowed to be inddefinite while the control weight operator is *** the exponential stabilization condition,it is proved that any optimal control and its optimal trajectory are *** positive real lemma as a necessary and sufficient condition for the unique solvability of this problem is *** closed-loop synthesis of optimal control is given via the solution to the algebraic Riccati equation.

关键词： Infinite horizon LQ problem Unbounded control Two-point boundary value problem Algebraic Riccati equation frequency characteristic

A Comparative Study on the Excitation of Large Volume Airgun Source with Different Combinations in Hutubi,Xinjiang,China

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Earthquake Research in China 2019年第4期33卷 573-583,I0001页

作者： SU Jinbo WANG Qiong CHEN Hao WEI Yunyun ZHANG Wenxiu WANG Haitao Earthquake Agency of Xinjiang Uygur Autonomous Region Urumqi 830011China The First Monitoring and Application Center CEATianjin 300180China China Earthquake Networks Center Beijing 100045China

In order to study the excitation of large-volume airgun source with different combinations in Hutubi,Xinjiang,China,we conducted a targeted *** method of timefrequency analysis is used to study the signals recorded by a seismometer on the shore of the excited pool,and it is concluded that different gun combinations will lead to different frequency of bubble pulse ***,linear combination method is used to analyze the signal-to-noise ratios of signals excited by different gun combinations which was recorded by seismic stations around the airgun *** order to improve the signal-tonoise ratios,it is more effective to increase the activation energy(the number of excited guns at the same time)than to stack the excited signals with smaller energy repeatedly.

关键词： Airgun source Different gun combinations Energy characteristic frequency characteristic Signal-to-noise ratio

Robust CMOS phase frequency detector for high speed and low jitter charge pump PLL

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Journal of Southeast University(English Edition) 2008年第1期24卷 15-19页

作者：周建政王志功东南大学射频与光电集成电路研究所合肥工业大学计算机与信息学院合肥230009

In order to improve the performance of the existing phase frequency detectors （PFDs）, a systematical analysis of the existing PFDs is presented. Based on the circuit architecture, both classifications and comparisons are made. A new robust CMOS phase frequency detector for a high speed and low jitter charge pump phrase-locked loop （PLL） is designed. The proposed PFD consists of two rising-edge triggered dynamic D flip-flops, two positive-edge detectors and delaying units and two OR gates. It adopts two reset mechanisms to avoid the LIP and DN signals to be logic-1 simultaneously. Thus, any current mismatch of the charge pump circuit will not worsen the performance of the PLL. Furthermore, it has hardly any dead-zone phenomenon in phase characteristic. Simulations with ADS are performed based on a TSMC 0. 18-μm CMOS process with a 1.8-V supply voltage. According to the theoretical analyses and simulation results, the proposed PFD shows a satisfactory performance with a high operation frequency （≈ 1 GHz）, a wide phase-detection range [ ± 2π], a near zero dead-zone （〈 0. 1 ps）, high reliability, low phase jitter, low power consumption （ ≈100 μW） and small circuit complexity.

关键词： phase frequency detectors dead-zone blind-zone phase characteristic frequency characteristic