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CSEE Journal of power and Energy Systems 2022年第3期8卷 710-720页

作者： Lin Yu Huadong Sun Shiyun Xu Bing Zhao Jian Zhang State Key Laboratory of power Grid Safety and Energy Conservation China Electric Power Research InstituteBeijing100192China

The power system is experiencing a higher penetration of renewable energy generations(REGs).The short circuit ratio(SCR)and the grid impedance ratio(GIR)are two indices to quantify the system strength of the power system with *** this paper,the critical short circuit ratio(CSCR)is defined as the corresponding SCR when the system voltage is in the critical stable *** static voltage stability analysis,the mathematical expression of the CSCR considering the impact of GIR is *** maximum value of CSCR is adopted as the critical value to distinguish the weak power *** on the static equivalent circuit analysis,it is proved that the CSCR is still effective to evaluate critical system strength considering the interactive impact among ***,we find that the GIR can be neglected and the SCR can be used individually to evaluate the system strength when SCR>2 or GIR>*** correctness and rationality of the CSCR and its critical value are validated on ADPSS.

关键词： Critical short circuit ratio critical value grid impedance ratio maximum power transfer theorem static equivalent circuit analysis

晶格畸变增强卤化锑晶体团簇的自陷激子发射（英文）

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Science china Materials 2025年第1期 132-140页

作者：刘达何敬敬孙玉婷刘心翊彭玉李庆杨化桂牛强杨双侯宇 Key Laboratory for Ultrafine Materials of Ministry of Education Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology china National Enterprise Technology Center Inner Mongolia Erdos Electric Power and Metallurgy Group Company Limited

零维钙钛矿材料以自陷激子引起的宽带发射为特征,是一种很有前途的刺激响应和光加密材料.然而,现有的研究主要集中在结构相变对光物理性质的影响上,对自陷激子的发射机制缺乏深入了解.本文证明了零维卤化锑单晶中的脱水反应,在不诱导结...

零维钙钛矿材料以自陷激子引起的宽带发射为特征,是一种很有前途的刺激响应和光加密材料.然而,现有的研究主要集中在结构相变对光物理性质的影响上,对自陷激子的发射机制缺乏深入了解.本文证明了零维卤化锑单晶中的脱水反应,在不诱导结构相变的基础上显著增强了自陷激子的发射,导致光致发光量子产率从3.5%大幅提高到91.4%.利用原位X射线衍射和光致发光技术揭示了晶体结构和光致发光强度之间的定性关系,证明了在脱水过程中引入了丰富的晶格畸变.温度依赖的荧光光谱和瞬态吸收光谱表明,晶格畸变导致中等的电子-声子耦合强度和更高的激子结合能,加速了自陷激子从非辐射复合单重态弛豫到辐射复合三重态,进而表现出增强的光致发光.作为概念验证,在防伪、可重写发光纸和湿度传感等多重场景中实现了应用.这一发现阐明了自陷激子的发射机制,并为设计可切换发光材料提供了一条新途径.

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Distributionally robust optimization model of active distribution network considering uncertainties of source and load

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Journal of Modern power Systems and Clean Energy 2019年第6期7卷 1585-1595页

作者： Lei DONG Jia LI Tianjiao PU Naishi CHEN power System research institute North China Electric Power UniversityBeijing 102206China china electric power research institute Beijing 100192China

To ensure the safety and reliability of the distribution network and adapt to the uncertain development of renewable energy sources and loads,a two-stage distributionally robust optimization model is proposed for the active distribution network(ADN)optimization problem considering the uncertainties of the source and load in this *** establishing an ambiguity set to capture the uncertainties of the photovoltaic(PV)power,wind power and load,the piecewise-linear function and auxiliary parameters are introduced to help characterize the probability distribution of uncertain *** optimization goal of the model is to minimize the total expected cost under the worst-case distribution in the ambiguity *** first-stage expected cost is obtained based on the predicted value of the uncertainty *** second-stage expected cost is based on the actual value of the uncertainty variable to solve the first-stage *** generalized linear decision rule approximates the two-stage optimization model,and the affine function is introduced to provide a closer approximation to the second-stage optimization ***,the improved IEEE 33-node and IEEE 118-node systems are simulated and analyzed with deterministic methods,stochastic programming,and robust optimization methods to verify the feasibility and superiority of the proposed model and algorithm.

关键词： Active distribution network(ADN) Source-load uncertainty Two-stage distributionally robust optimization Ambiguity set Generalized linear decision rule

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Predicting transformer temperature field based on physics-informed neural networks

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High Voltage 2024年第4期9卷 839-852页

作者： Pengfei Tang Zhonghao Zhang Jie Tong Tianhang Long Can Huang Zihao Qi china electric power research institute BeijingChina

The safe operation of oil-immersed transformers is critical to the safety and stability of the power *** the operating time increases,the failure rate of oil-immersed transformers shows an increasing trend,posing serious challenges to safe *** is necessary to investigate the internal state of the oil-immersed transformer to improve the digital degree and achieve digitalisation and intelligent operation and maintenance.A physics-informed neural network(PINN)for oil-immersed transformers was introduced to reconstruct the temperature distribution inside the *** to the approach,the loss function of the network would be optimised by incorporating physical constraint loss terms including heat transfer equations,initial conditions and boundary *** results show that the method proposed can be used to reconstruct and predict the temperature field of transformers in a few seconds with satisfactory *** conclusion,the PINN proposed outperforms deep neural networks in terms of accuracy,reliability and interpretability,especially in data-poor cases.

关键词： immersed conclusion constraint

Economic optimization on two time scales for a hybrid energy system based on virtual storage

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Journal of Modern power Systems and Clean Energy 2018年第5期6卷 1004-1014页

作者： Jingjie YANG Bingqing GUO Bo QU china electric power research institute

This paper proposes an economic optimization method with two time scales for a hybrid energy system based on the virtual storage characteristic of a thermostatically controlled load(TCL). The optimization process includes two time scales in order to ensure accuracy and efficiency. Based on the forecast load and energy supply of the system, the first time scale is day-ahead economic operating optimization, carried out to determine the minimum operating cost for the whole day, and to find the period of greatest cost to which the second time scale optimization is applied. Using the virtual storage characteristic, the second time scale is short-term detailed optimization carried out for these particular hours. By dispatching thermal load in this period and adjusting energy supply accordingly, we can find the optimal economic performance, and customer requests are taken into account to ensure satisfaction. A case study in Tianjin, china illustrates the effectiveness of this method and proves that a TCL can make a great contribution to improving the economic performance of a hybrid energy system.

关键词： Economic optimization Hybrid energy system Virtual storage Two time scales Heating ventilation and air conditioning(HVAC) system

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Graph Computing and Its Application in power Grid Analysis

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CSEE Journal of power and Energy Systems 2022年第6期8卷 1550-1557页

作者： Mike Zhou Jianfeng Yan Qianhong Wu china electric power research institute Beijing 100192China

Approaches to apply graph computing to power grid analysis are systematically explained using real-world application *** exploring the nature of the power grid and the characteristics of power grid analysis,the guidelines for selecting appropriate graph computing techniques for the application to power grid analysis are outlined.A custom graph model for representing the power grid for the analysis and simulation purpose and an in-memory computing(IMC)based graph-centric approach with a shared-everything architecture are *** algorithms,including network topology processing and subgraph processing,and graph computing application scenarios,including in-memory computing,contingency analysis,and Common Information Model(CIM)model merge,are presented.

关键词： CIM model merge contingency analysis Graph computing in-memory computing network topology processing power grid analysis subgraph processing

Collaborative Fault Recovery and Network Reconstruction Method for Cyber-physical-systems Based on Double Layer Optimization

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CSEE Journal of power and Energy Systems 2023年第1期9卷 380-392页

作者： Wanxing Sheng Keyan Liu Zhao Li Xueshun Ye china electric power research institute Beijing 100192China

For fault characteristics of cyber-physical-systems(CPS)based distribution network,a spatiotemporal incidence matrix to represent correlation of concurrent faults on cyberspace and physical space is proposed,and strategies of fault location,removal,and recovery of concurrent faults are analyzed in this *** the multiple objectives of minimum network loss,voltage deviation,and switching operation times,a collaborative power supply restoration model of a CPS-based distribution network with the strategy that restoration of the communication layer is prior to the physical layer is constructed using the Dijkstra’s dynamic routing algorithm and second-order cone relaxation distribution network reconfiguration method,to realize orderly recovery of a distribution network during CPS concurrent *** investigations are made based on the DCPS-160 case,and the accuracy and effectiveness of the proposed model are also verified.

关键词： Collaborative fault cyber-physical-systems distribution network double layer optimization

Coordination Control Method for Preventing Sub/Super Synchronous Oscillations of Multi-wind Farm Systems

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CSEE Journal of power and Energy Systems 2023年第5期9卷 1655-1665页

作者： Guoqing He Weisheng Wang Haijiao Wang china electric power research institute Beijing 100192China

In recent years,sub/super-synchronous oscillations occur frequently in large-scale wind power bases throughout *** the oscillation frequencies are close to the fundamental frequency,the current components can spread over a large area,and may destroy the shafting of rotating devices in the power *** the control strategy and parameters of wind turbines can prevent this problem to some extent,however,due to complex operational conditions and continuous development of wind power,the off-line improvement measures on wind turbines cannot eliminate the potential oscillation *** paper proposes an oscillation risk screening and stability assessment method,and develops a coordination control method for large-scale wind farm systems to prevent sub/supersynchronous *** Nyquist criterion and the modal analysis method are combined to generate quantitative factors for the stability assessment and the control strategy *** coordination control method consists of minute-level power coordinated allocation and second-level fast power control to prevent and eliminate the oscillations.A detailed simulation model of a multiple wind farms system originated from an actual wind power base in china is presented to verify the effectiveness of the proposed method.

关键词： Coordination control prevention sequence impedance sub/super-synchronous oscillations wind farm

Parameter Identification for Static Var Compensator Model Using Sensitivity Analysis and Improved Whale Optimization Algorithm

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CSEE Journal of power and Energy Systems 2022年第2期8卷 535-547页

作者： Qiang Guo Lei Gao Xiaojie Chu Huadong Sun china electric power research institute Beijing 100192China

A parameter estimation method based on an improved Whale Optimization Algorithm is proposed in this paper to identify the parameters of a static var compensator(SVC)***,a mathematical model of SVC is ***,the reverse learning strategy and Levy flight disturbance strategy are introduced to improve the whale optimization algorithm,and the improved whale optimization algorithm is applied to the parameter identification of the static var compensator ***,a stepwise identification method,by analyzing the local sensitivities of parameters,is proposed which solves the problem of low accuracy caused by multi-parameter *** method provides a new estimation strategy for accurately identifying the parameters of the static var compensator *** results show that the parameter estimation method can be an effective tool to solve the problem of parameter identification for the SVC model.

关键词： Local sensitivity analysis parameter estimation static var compensator model stepwise identification method whale Optimization Algorithm

Damping Characteristic Analysis and Optimization of Wind-thermal-bundled power Transmission by LCC-HVDC Systems

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Journal of Modern power Systems and Clean Energy 2024年第1期12卷 299-312页

作者： Liwen Zheng Shiying Ma the power System Department China Electric Power Research InstituteBeijing 100192China

With the rapid development of renewable energy,wind-thermal-bundled power transmission by line-commutated converter based high-voltage direct current(LCC-HVDC)systems has been widely *** dynamic interaction mechanisms among permanent magnet synchronous generators(PMSGs),synchronous generators(SGs),and LCC-HVDC system become *** deal with this issue,a path analysis method(PAM)is proposed to study the dynamic interaction mechanism,and the damping reconstruction is used to analyze the damping characteristic of the ***,based on the modular modeling,linearized models for the PMSG subsystem,the LCC-HVDC subsystem,and the SG subsystem are ***,based on the closed-loop transfer function diagram of the system,the disturbance transfer path and coupling relationship among subsystems are analyzed by the PAM,and the damping characteristic analysis of the SG-dominated oscillation mode is studied based on the damping *** with the PAM,the small-signal model of the system is obtained and eigenvalue analysis results are ***,the effect of the control parameters on the damping characteristic is analyzed and the conclusions are verified by time-domain ***,the penalty functions of the oscillation modes and decay modes are taken as the objective function,and an optimization strategy based on the Monte Carlo method is proposed to solve the parameter optimization *** simulation results are presented to validate the effectiveness of the proposed strategy.

关键词： Wind-thermal-bundled power transmission line-commutated converter based high-voltage direct current(LCC-HVDC) path analysis method(PAM) damping characteristic analysis Monte Carlo method

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