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Experimental Demonstration of Ground Plane Immunity for Magnetoelectric Antennas

Experimental Demonstration of Ground Plane Immunity for Magn...

IEEE MTT-S International Microwave Workshop Series on advanced Materials and Processes for RF and THz Applications (IMWS-AMP)

作者： Xianfeng Liang Huaihao Chen Zhongqiang Hu Hwaider Lin Hui Huang Jinghong Guo Dengfeng Ju Ming Liu Nian X. Sun Institute of Electric Power Sensing Technology State Grid Smart Grid Research Institute Co. LTD. Beijing China Department of Electrical and Computer Engineering Northeastern University Boston USA Electronic Materials Research Laboratory Key Laboratory of the Ministry of Education & International Center for Dielectric Research School of Electronic Science and Engineering Xi’an Jiaotong University Xi’an China Winchester Technologies LLC Burlington MA USA

Compact and low-profile antennas that can be mounted on the plane surface have been researched considerably for decades in communication systems. However, when the planar antennas are placed on a metallic surface, the radiation from the antennas can be canceled out by the imaging current. By utilizing acoustic wave resonance rather than relying on electromagnetic (EM) wave resonance, a novel mechanically driven antenna because of the magnetoelectric (ME) effect was proposed to have a ground plane immunity property. In this paper, a general review of the development of ME antennas is first presented. And then a section is dedicated to introducing the theory and the experimental demonstration of ground plane immunity for ME antennas. Finally, further designs to enhance the antenna performance and future applications of employing ME antennas are presented.

关键词： Microwave antennas Radio frequency Magnetic resonance imaging Surface acoustic waves Magnetoelectric effects Magnetoacoustic effects Planar arrays

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LightGBM-Based Prediction of Remaining Useful Life for Electric Vehicle Battery under Driving Conditions

LightGBM-Based Prediction of Remaining Useful Life for Elect...

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2020 IEEE Sustainable power and Energy Conference, iSPEC 2020

作者： Liu, Huiqiao Xiao, Qian Jiao, Zhipeng Meng, Jinhao Mu, Yunfei Hou, Kai Yu, Xiaodan Guo, Shiqi Jia, Hongjie Zhonghuan Information College Tianjin University of Technology Department of Automation Engineering Tianjin China Key Laboratory of Smart Grid of Ministry of Education Tianjin University Tianjin China State Key Laboratory of Reliability and Intelligence of Electrical Equipment Hebei University of Technology Tianjin China College of Electrical Engineering Sichuan University Chengdu China State Grid Tianjin Binhai Electric Power Supply Company Tianjin China

ISBN: (纸本)9781728191645

Remaining useful life (RUL) prediction for electric vehicle battery (EV battery) is of great significance for the early replacement and regular maintenance of batteries with potential safety hazards in driving conditions. This paper proposes a novel method based on light gradient boosting machine (LightGBM) to predict the RUL of the battery under driving conditions. LightGBM uses the histogram optimization strategy to reduce the number of traversal of the data sample set and improve the robustness of the method;the depth-first splitting (leaf-wise) strategy reduces the risk of overfitting;the gradient-based one-sided sampling strategy (GOSS), reduce the data dimension;use the exclusive feature bundling strategy (EFB) to reduce the feature dimension. However, the LightGBM method has the difficulty of parameter setting. Therefore, this paper uses Hyperopt based on distributed asynchronous algorithm configuration/hyperparameter optimization to optimize its complicated hyperparameters. Subsequently, the method was applied to the prediction of battery RUL under simulated driving conditions. Based on the comparative cases, the results show that this method can guarantee the rapidity, accuracy and robustness of RUL prediction under the condition of low memory usage. © 2020 IEEE.

关键词： Forecasting

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The influence of adjacent lines on the surface electric field of outage maintenance personnel

The influence of adjacent lines on the surface electric fiel...

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22nd International Symposium on High Voltage Engineering (ISH 2021)

作者： X. Lingzhi C. Dengfeng C. Yang D. Zhiyuan S. Keer State Grid Anhui Electric Power Co. Ltd. Electric Power Research Institute Hefei People's Republic of China State Key Laboratory of Power Transmission Equipment & System Security and New Technology (Chongqing University) Chongqing People's Republic of China

In this paper, the induced electric field generated by the adjacent ±800 kV UHV line on the body surface of ±1100 kV DC transmission line operators in outage maintenance is studied. The distribution characteristics of the electric field on the body surface of line maintenance personnel are obtained based on the upflow finite element method. The distribution of electric field on the human body surface at five typical operation locations commonly used for line maintenance is simulated and measured on site. The simulation results show that when ±1100 kV line is shut down for maintenance, no matter where the working location is, the induced electric field on the operator's body surface caused by adjacent UHV line is generally small, and the electric field at the tip of human body is too large. The maximum is no more than 13 kV/m, and the field strength of smooth parts such as the trunk is very small. The electric field on the body surface decreases with the increase of line spacing, and the decline rate of the tip of the body is less than that of the smooth part. The field measured data verify the reliability of the simulation results.

关键词： electric fields finite element analysis HVDC power transmission power transmission lines

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Fast power Flow Calculation Method for Electricity Hydrogen Storage Integrated Energy Network

Fast Power Flow Calculation Method for Electricity Hydrogen ...

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IEEE Conference on Energy Internet and Energy System Integration (EI2)

作者： Zhijun Liu Haijun Liu Shuai Wang Bin Ge Jiawei Li Siwei Liu Runhao Gao Xiaoling Su Zhangjiakou Chongli District Power Supply Branch State Grid Jibei Electric Power Company Zhangjiakou China State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research Institute co. Ltd Beijing China Qinghai Key Lab of Efficient Utilization of Clean Energy School of Water Resources and Electric Power Qinghai University China

ISBN: (纸本)9781665434263

power system has developed significantly because of the increasing share of renewable energy sources (RESs). Despite the advantages, they also bring inevitable challenges to power system stability. Hydrogen energy plays an indispensable role in the process of energy transformation. This paper presents fast power flow calculation method for integrated energy network which contains PV, wind farm and hydrogen storage system. Energy hub model is developed to analyze the interaction between the power system and hydrogen system in steady-state operation. The mathematical model includes power grid, hydrogen network, PV and wind generation, hydrogen storage system, energy hub and power loss. Gauss-Seidel iterate method and Newton-Raphson method are applied to calculate the power flow calculation model of integrated energy system. Finally, a calculation example is used to verify the effectiveness of the proposed model and calculation algorithm.

关键词： Wind energy generation Renewable energy sources Hydrogen power system stability Wind power generation Wind farms Mathematical models

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Acid and alkali resistance of cycloaliphatic epoxy resin insulators 1

Acid and alkali resistance of cycloaliphatic epoxy resin ins...

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1st IEEE China International Youth Conference on Electrical Engineering, CIYCEE 2020

作者： Yin, Li Zhang, Chong Yang, Wei Tian, Ye Yan, Bingyue Wang, Yunsong Liu, Yuhao Global Energy Interconnection Research Institute Co. Ltd State Key Laboratory of Advanced Power Transmission Technology Beijing102209 China Electric Power Research Institute of State Grid Liaoning Electric Power Co. Ltd. Shenyang110006 China Tsinghua University Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate School Shenzhen518055 China

ISBN: (纸本)9781728196596

In order to study the acid and alkali resistance of the novel hard cycloaliphatic epoxy resin insulator sheath material, two frequently used cycloaliphatic epoxy resins (hexahydrohsphenol-A diglycidyl ether/ hexahydrophthalate diglycidyl ester) are selected and immersed in 2% HCl and NaOH solution at room temperature (25°C). Through surface roughness, static contact angle, scanning electron microscope and fourier infrared spectroscopy tests, the surface morphology and chemical structure stability of the two cycloaliphatic epoxy resins under different immersion times are analyzed. The results show that both cycloaliphatic epoxy resins do not have obvious corrosion in acidic environment, but in alkaline environment, both cycloaliphatic epoxy resins are corroded and aged. The corrosion of cycloaliphatic epoxy resins in acidic and alkaline environments originates from hydrolysis of ester bonds, so the corrosion of hexahydrophthalate diglycidyl ester with more ester bonds is more severe. © 2020 IEEE.

关键词： Surface roughness

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Research on water absorption characteristic of cycloaliphatic epoxy resin insulator 1

Research on water absorption characteristic of cycloaliphati...

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1st IEEE China International Youth Conference on Electrical Engineering, CIYCEE 2020

作者： Yin, Li Zhang, Chong Yang, Wei Tian, Ye Yan, Bingyue Liu, Yuhao Wang, Yunsong Global Energy Interconnection Research Institute Co. Ltd State Key Laboratory of Advanced Power Transmission Technology Beijing102209 China Electric Power Research Institute of State Grid Liaoning Electric Power Co. Ltd. Shenyang110006 China Tsinghua University Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate School Shenzhen518055 China

ISBN: (纸本)9781728196596

The water absorption characteristic of the base resin of cycloaliphatic epoxy resin insulators were studied. Hydrogenated bisphenol A glycidyl ether resin (EP-A) and diglycidyl 1, 2-cyclohexanedicarboxylate resin (EP-B) were immersed in deionized water at 80°C. It was found that the water uptake of the both of cycloaliphatic epoxy resins increased with the increase of soaking time. The water absorption of EP-A is mainly caused by Fick diffusion and internal molecular relaxation. The water absorption of EP-B is mainly attributed to Fick diffusion and surface micro cracks and voids formed by aging. The water absorption of the two kinds of resins can be described by Diffusion-Relaxation model. The moisture diffusion coefficient D of EP-B is less than that of EP-A at the initial stage of water absorption, which indicates the better property to inhibit the water penetration into the interface. Compared with EP-B, EP-A has better hydrolysis resistance. © 2020 IEEE.

关键词： Water absorption

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Distance protection of EHV long transmission lines considering compensation degree of shunt reactor

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Global Energy Interconnection 2019年第1期2卷 64-70页

作者： Wang Jiang Jiping Lu Hongji Xiang Xing Ma Hui Fang State Grid Chongqing Electric Power Company Electric Power Research Institute State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University

This study investigated the feasibility of distance protection in extra-high voltage(EHV) networks. In long-distance transmission lines, the distributed parameter characteristic of the EHV network is obvious. When a fault occurs far away from the measurement site, the measured impedance might not be directly proportional to the fault distance, and the protection domain of distance protection will be decreased. The detailed theory inferred and proven in this paper reveals that this phenomenon is widespread in EHV transmission lines. The results indicate that the protection domain error is greatly reduced by the application of the shunt reactor. Overall, simulation results show that the proposed method is effective for impedance relay, considering different characteristics, different lengths of lines, and compensation degrees.

关键词： EHV Distance protection Shunt reactor Compensation degree

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Protection and Fault Recovery Strategy of AC and DC System of Flexible Substation 8

Protection and Fault Recovery Strategy of AC and DC System o...

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8th IEEE International Conference on advanced power System Automation and Protection, APAP 2019

作者： Huanhuan, Qi Zhanfeng, Deng Guoliang, Zhao Zhengang, Lu Zhe, Zhou Zhao, He Global Energy Interconnection Research Institute Co. Ltd State Key Laboratory of Advanced Power Transmission Technology Beijing China State Grid Corporation of China State Grid Beijing Electric Power Corporation Beijing China

ISBN: (纸本)9781728117225

The AC and DC system of flexible substation have been applied in the project, and it is imperative to study the protection scheme. Based on the basic structure of the AC and DC system of flexible substation, the partitioned and layered protection scheme are proposed. Both the component-level and the station-level protection configuration schemes are proposed. Based on two flexible substations connected to the grid, the fault recovery strategy is proposed, and the fault recovery processes of 10kV AC line fault and ± 10kV DC line fault of two flexible substations are simulated and analyzed. The simulation results are consistent with the proposed strategy. The proposed fault recovery strategy has reference significance for the device or system composed of converter interconnections in multiple operating states. © 2019 IEEE.

关键词： AC and DC system Fault isolation Fault recovery Flexible substation Protection

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Design and Research of an Optical Transient Overvoltage Sensor

Design and Research of an Optical Transient Overvoltage Sens...

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Electrical Engineering and Automation (IFEEA), International Forum on

作者： Xin Li Jing Xiao Hualong Deng Qing Yang State Grid Hunan Electric Power Co. Ltd Electric Power Research Institute Changsha China Hunan Changgao Senyuan Power Equipment Co. Ltd Hengyang China State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing China

The safe and reliable operation of the power system is a prerequisite for ensuring the normal operation of the national economy and other sectors. To improve the efficiency and reliability of power grid operation, this paper designs an optical transient overvoltage sensor based on the Pockels effect principle. Through comparative analysis of the physical properties of different electro-optic crystal materials, a reasonable selection of the applicable electro-optic crystal materials. A voltage measurement platform was built in the laboratory, and the power frequency response characteristics, amplitude-frequency characteristics, and high-frequency impulse voltage response characteristics of the sensor were analyzed separately. And the accuracy of waveform restoration is improved by optimizing the output waveform of the sensor. Finally, the layout method and overall packaging scheme of the sensor’s constituent units are proposed, which has high engineering application value.

关键词： Voltage measurement Optical design Crystals Reliability engineering Adaptive optics power system reliability Optical sensors

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A novel fiber-optic implantable basin insulator and its detection of current-excited GIS vibration signals

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Measurement 2025年 256卷

作者： Yuxuan Song Anqi Tao Weigen Chen Weikai Zhang Changding Wang Xiaosong Zhu Bo Liu Haoyuan Tian Hong Liu State Key Laboratory of Power Transmission Equipment Technology Chongqing University Chongqing 400044 China State Grid Chongqing Electric Power Company Research Institute Chongqing 401120 China Shangdong Taikai High Voltage Switchgear Co. Ltd. Taian 271000 China

In this paper, a fiber optic implanted basin insulator and its fiber optic interferometric demodulation system are proposed for detecting mechanical vibration acceleration signals in GIS. The fiber optic sensor is integrated with the GIS basin insulator for theoretically long-term reliability and resistance to electromagnetic interference. The fiber-optic basin insulator implanted with sensing fibers is developed and verified to have good electrical characteristics through multiphysics field simulation and type test. Three typical mechanical faults of GIS current-excited devices are set up, and vibration monitoring experiments are carried out based on a real-type three-phase common box 126 kV GIS device. The experimental results verify the sensitivity and field applicability of the developed implanted sensing fiber basin insulator and sensing system for measuring vibration acceleration signals under normal and fault conditions. The study provides a new idea for the development of self-aware components for GIS equipment.

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