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Chinese Physics B 2013年第8期22卷 620-626页

作者：伍展文李洁黎松林郑东宁 Beijing National Laboratory for Condensed Matter Physics & institute of Physics Chinese Academy of Sciences institute of Testing and research Zhongshan Power Supply Bureau Guangdong Power Grid Corporation

Epitaxial La2/3Cal/3MnO3 thin films grown on LaA103 （001） substrates were irradiated with low-energy 120-keV H＋ ions over doses ranging from 1012 ions/cm2 to 1017 ions/cm2. The irradiation suppresses the intrinsic insulator-metal （I-M） transition temperature and increases the resistance by reducing the crystallographic symmetry of the films. No irradiation-induced columnar defects were observed in any of the samples. The specific film irradiated at a critical dose around 8 x 1015 ions/cm2 is in a threshold state of the electric insulator where the I-M transition is absent. In an external field of 4 T or higher, the I-M transition is restored and thus an enormous magnetoresistance is observed, while a negative temperature coefficient resumes as the temperature is reduced further. Magnetic relaxation behavior is confirmed in this and other heavily irradiated samples. The results are interpreted in terms of the displacement of oxygen atoms provoked by ion irradiation and the resulting magnetic glassy state, which can be driven into a phase coexistence of metallic ferromagnetic droplets and the insulating glass matrix in a magnetic field.

关键词： manganite ion irradiation magnetoresistance

Situation Awareness and Sensitivity Analysis for Absorption of Grid-connected Renewable Energy power Generation Integrating Robust Optimization and Radial Basis Function Neural Network

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Journal of Modern power Systems and Clean Energy 2023年第6期11卷 1795-1803页

作者： Ziqi Zhang Zhong Chen Qi Zhao Yi Wang Jiang Tian School of Electrical Engineering Southeast UniversityNanjingChina Suzhou power Supply Branch of the state Grid Jiangsu Electric power Company SuzhouChina NARI Group corporation Ltd. (State Grid Electric Power Research Institute Ltd.)NanjingChina

The significance of situation awareness(SA) in power systems has increased to enhance the utilization of gridconnected renewable energy power generation(REPG). This paper proposes a real-time calculation architecture based on the integration of robust optimization(RO) and artificial intelligence. First, the time-series simulation of the REPG consumption capacity is carried out under the current grid operating conditions. RO is employed in this simulation, given the randomness of the REPG output and the grid load. Then, the radial basis function neural network(RBFNN) is trained with the results under different parameters using the artificial fish swarm algorithm(AFSA), enabling the neural network(NN) to be the replacement for the time-series simulation model. The trained NN can quickly perceive the REPG absorption situation within the predefined grid structure and period. Moreover, the Sobol' method is adopted to conduct the global sensitivity analysis for different parameters based on the input-output samples obtained by the trained NN. Finally, the simulation experiments based on the modified IEEE 14-bus system prove the real-time performance and accuracy of the proposed SA architecture.

关键词： Renewable energy radial basis function neural network robust optimization sensitivity analysis situation awareness

Sample Generation for Security Region Boundary Identification Based on Topological Features of Historical Operation Data

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Journal of Modern power Systems and Clean Energy 2024年第4期12卷 1087-1095页

作者： Xiaokang Wu Wei Xu Feng Xue College of Energy and Electrical Engineering Hohai UniversityNanjingChina NARI Group corporation NanjingChina state Grid Electric power research institute NanjingChina

Since the scale and uncertainty of the power system have been rapidly increasing,the computation efficiency of constructing the security region boundary(SRB)has become a prominent *** on the topological features of historical operation data,a sample generation method for SRB identification is proposed to generate evenly distributed samples,which cover dominant security *** boundary sample pair(BSP)composed of a secure sample and an unsecure sample is defined to describe the feature of *** resolution,sampling,and span indices are designed to evaluate the coverage degree of existing BSPs on the SRB and generate samples closer to the *** on the feature of flat distribution of BSPs over the SRB,the principal component analysis(PCA)is adopted to calculate the tangent vectors and normal vectors of ***,the sample distribution can be expanded along the tangent vector and corrected along the normal vector to cover different security ***,a sample set is randomly gen-erated based on the IEEE standard example and another new sample set is generated by the proposed *** results indicate that the new sample set is closer to the SRB and covers different security modes with a small calculation time cost.

关键词： Clustering analysis principal component analysis(PCA) sample generation security region boundary(SRB)

Stochastic convergence analysis of cubature Kalman filter with intermittent observations

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Journal of Systems Engineering and Electronics 2018年第4期29卷 823-833页

作者： SHI Jie QI Guoqing LI Yinya SHENG Andong School of Automation Nanjing University of Science and TechnologyNanjing 210094China NARI Group corporation/state Grid Electric power research institute Nanjing 211000China

The stochastic convergence of the cubature Kalmanfilter with intermittent observations （CKFI） for general nonlinearstochastic systems is investigated. The Bernoulli distributed ran-dom variable is employed to describe the phenomenon of intermit-tent observations. According to the cubature sample principle, theestimation error and the error covariance matrix （ECM） of CKFIare derived by Taylor series expansion, respectively. Afterwards, itis theoretically proved that the ECM will be bounded if the obser-vation arrival probability exceeds a critical minimum observationarrival probability. Meanwhile, under proper assumption corre-sponding with real engineering situations, the stochastic stabilityof the estimation error can be guaranteed when the initial estima-tion error and the stochastic noise terms are sufficiently small. Thetheoretical conclusions are verified by numerical simulations fortwo illustrative examples; also by evaluating the tracking perfor-mance of the optical-electric target tracking system implementedby CKFI and unscented Kalman filter with intermittent observa-tions （UKFI） separately, it is demonstrated that the proposed CKFIslightly outperforms the UKFI with respect to tracking accuracy aswell as real time performance.

关键词： cubature Kalman filter (CKF) intermittent observation estimation error stochastic stability.

Decision Support System for Adaptive Restoration Control of Transmission System

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Journal of Modern power Systems and Clean Energy 2021年第4期9卷 870-885页

作者： Ze Li Yusheng Xue Haohao Wang Lili Hao School of Electrical Engineering Southeast UniversityNanjingChina state Grid Electric power research institute(NARI Group corporation) NanjingChina state Grid Electric power research institute(NARI Group corporation) NanjingChinaand they are also with State Key Laboratory of Smart Grid Protection and Operation ControlNanjingChina School of Electrical Engineering and Control Science Nanjing Tech UniversityNanjingChina

The power system restoration control has a higher uncertainty level than the preventive control of cascading failures. In order to ensure the feasibility of the decision support system of restoration control, a decision support framework for adaptive restoration control of transmission system is proposed, which can support the coordinated restoration of multiple partitions, coordinated restoration of units and loads, and coordination of multi-partition decision-making process and actual restoration process. The proposed framework is divided into two layers, global coordination layer and partition optimization layer. The upper layer partitions the transmission system according to the power outage scenario, constantly and dynamically adjusts the partitions during the restoration process, and optimizes the time-space decision-making of inter-partition connectivity. For each partition, the lower layer pre-selects restoration targets according to the estimated restoration income, optimizes the corresponding restoration paths, and evaluates the restoration plans according to the expected net income per unit of power consumption. During the restoration process, if the restoration operation such as energizing the outage branch fails, the current restoration plan will be adaptively switched to the sub-optimal one or re-optimized if necessary. The framework includes two operation modes, i.e., the on-line operation mode and training simulation mode, and provides an information interaction interface for collaborative restoration with related distribution systems. The effectiveness and adaptability of the proposed framework is demonstrated by simulations using the modified IEEE 118-bus system.

关键词： Transmission system restoration two-layer decision support framework restoration risk and income restoration uncertainty sand table deduction

Subsynchronous resonance and its mitigation for power system with unified power flow controller

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Journal of Modern power Systems and Clean Energy 2018年第1期6卷 181-189页

作者： Xinyao ZHU Meng JIN Xiangping KONG Jingbo ZHAO Jiankun LIU Qian ZHOU state Grid Jiangsu Electric power research institute state Grid Jiangsu Electric power Maintenance Branch Company

Control strategy of unified power flow controller(UPFC)utilizing dq decoupling control is deduced in this paper,which can closely follow the control orders of the active and reactive *** subsynchronous resonance(SSR)characteristics of a series compensated system equipped with UPFC are studied,and the results reveal that SSR characteristics of the system may vary significantly with UPFC in service or ***,supplementary subsynchronous damping controller(SSDC)for UPFC is proposed and investigated,and the effectiveness of the proposed SSDC is verified by damping torque analysis and time domain simulations.

关键词： Unified power flow controller(UPFC) Series capacitor compensation Subsynchronous resonance(SSR) Supplementary subsynchronous damping controller(SSDC) Damping torque analysis

High accuracy object detection via bounding box regression network

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Frontiers of Optoelectronics 2019年第3期12卷 324-331页

作者： Lipeng SUN Shihua ZHAO Gang LI Binbing LIU state Grid Hunan Electric power corporation Limited research institute Changsha 410007China state Grid Hunan Electric power corporation Limited Changsha 410007China School of Optical and Electronics Information Huazhong University of Science and TechnologyWuhan 430074China

As one of the primary computer vision problems, object detection aims to find and locate semantic objects in digital images. Different with object classification, which only recognizes an object to a certain class, object detection also needs to extract accurate locations of objects. In the state-of-the-art object detection algorithms, bounding box regression plays a critical role in order to achieve high localization accuracy. Almost all the popular deep learning based object detection algorithms have utilized bounding box regression for fine tuning of object locations. However, while bounding box regression is widely used, there is few study focused on the underlying rationale, performance dependencies, and performance evaluation. In this paper, we proposed a dedicated deep neural network for bounding box regression, and presented several methods to improve its performance. Some ad hoc experiments are conducted to prove the effectiveness of the network. Also, we apply the network as an auxiliary module to the faster R-CNN algorithm and test them on some real-world images. Experiment results show certain performance improvements on detection accuracy in term of mean IOU.

关键词： deep learning object detection bounding box regression IOU distribution

Statistical characteristics and mechanism analysis of adhered particle on surface under strong electric field

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Particuology 2019年第2期17卷 110-122页

作者： Yunpeng Jiang Lee Li Ming Lu Rumeng Wang Yiwen Jiang Shanfeng Liu Chao Su state Key Laboratory of Advanced Electromagnetic Engineering and Technology Huazhong University of Science & Technology Wuhan 430074 China state Grid Henan Electric power research institute Zhengzhou 450052 China Qingyuan power Supply Bureau of Guangdong power Grid corporation Guangdong 511515 China

Insulators on high-voltage Uansmission lines are almost the only man-made structures on the Earth's surface intended for long-term operation under strong electric fields. After samples of natural contaminant particles were collected from insulator surfaces in China, it was found that the particle diameter distribution (PDD) was mainly concentrated in the 5-50 μm range. To analyze the statistical characteristics of these particles, this work studies the physical processes of particle collision and adhesion using the theories of hydrodynamics and collision dynamics. The physical model considers coupling of the fluid field and the electric field, introduces an adhesion criterion, and establishes a particle and surface collision model. The effects of relative humidity, wind speed, aerodynamic shape, electric field type, and electric field strength on particle adhesion were analyzed. The results show that the relative humidity and wind speed have very significant effects and the influences of the electric field type and the electric field strength are obvious, but the in fluence of the aerodynamic shape is relatively weak. The simulation results support the statistical characteristics determined in this work. The physical model established here provides reference values for study of the adhesion characteristics of particles on surfaces under electric fields.

关键词： Contaminant particle Collision Adhesion Particle diameter Simulation analysis

Short-term Cooling,Heating and Electrical Load Forecasting in Business Parks Based on Improved Entropy Method 36

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Short-term Cooling,Heating and Electrical Load Forecasting i...

Transition towards higher penetration of renewables: an overview of interlinked technical, environmental and socio-economic challenges

第36届中国控制会议

作者： Ling Cheng Yu Zhang Li Suo Si Shen Fang Fang Lu Jin China Electrical power research institute state Grid Shanghai Municipal Electric power Company Electric power research institute NARI Group corporation/state Grid Electric power research institute The School of Control and Computer Engineering North China Electric Power University

ISBN: (纸本)9781538629185

Short-term cooling,heating and electrical load forecasting in business parks is the basis of safe and economical operation of the scheduling system,and its accuracy is largely influenced by the selection of similar *** order to improve the accuracy of load forecasting,a short-term load forecasting method based on improved entropy method is *** method is used in the similar day selection and the similar day weight determination *** overcomes the drawback of traditional entropy weight method that the information transferred by entropy weight and entropy value is inconsistent when all entropy values are close to *** verification example shows that this method can not only select the most suitable similar day from the historical day,but also has a faster computing speed than the conventional intelligent algorithm.

关键词： short-term cooling heating and electrical load forecasting improved entropy method similar days

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Journal of Modern power Systems and Clean Energy 2019年第1期7卷 1-8页

作者： Xinyu CHEN Michael B.MCELROY Qiuwei WU Yinbiao SHU Yusheng XUE John A.Paulson School of Engineering and Applied Sciences Harvard University Department of Electrical Engineering Technical University of Denmark state Grid corporation of China state Grid Electric power research institute

investment for renewables has been growing rapidly since the beginning of the new century, and the momentum is expected to sustain in order to mitigate the impact of anthropogenic climate *** towards higher renewable penetration in the power industry will not only confront technical challenges, but also face socio-economic *** connected between environment and energy systems are also tightened under elevated penetration of *** paper will provide an overview of some important challenges related to technical, environmental and socio-economic aspects at elevated renewable *** integrated analytical framework for interlinked technical, environmental and socio-economic systems will be presented at the end.

关键词： Wind power Solar power Integrated energy systems Missing money problem Low carbon policies