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Study on the fastening characteristics of preformed helical fittings considering the surface effect of transmission lines

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SCIENTIFIC REPORTS 2023年第1期13卷 1-21页

作者： Lv, Zhongbin Liu, Guanghui Li, Fangyu Wu, Chuan Tao, Yaguang Liu, Jufang Ye, Zhongfei Liu, Xiaohui Sun, Yuntao Bo, Yan Chongqing Univ Coll Aerosp Engn Chongqing 400044 Peoples R China State Grid Henan Elect Power Res Inst Zhengzhou 450052 Peoples R China Chongqing Jiaotong Univ Sch Civil Engn Chongqing 400074 Peoples R China BYD Co Ltd Shenzhen 518118 Peoples R China Chongqing Jiaotong Univ State Key Lab Mt Bridge & Tunnel Engn Chongqing 400074 Peoples R China Nanjing Elect Power Fittings Design & Res Inst Co Nanjing 210009 Peoples R China

Because of their superior mechanical properties, preformed helical fittings are widely used in UHV transmission lines. However, they easily slip and become loose under extreme environments, so it is very important to study the fastening characteristics of preformed helical fittings. According to the stress characteristics of preformed helical fittings, a parametric finite element model including a core and preformed armor rods was established. Finally, the finite element model calculation was verified by comparing it with the test results. In this paper, the influences of the preformed armor rod diameter, pitch, length and forming aperture on the fastening characteristics were investigated. The numerical simulation results showed that the smaller the forming aperture of preformed armor rods, the larger the grip force. However, a small forming aperture is inconvenient to install, and too large of a grip force on the core easily leads to core damage. With the increase in the preformed armor rod length, the grip force increased gradually and linearly, and the increase slowed after the pitch number reached 9. The larger the pitch, the smaller the grip force of the preformed helical fittings. The fastening characteristics of preformed armor rods with slightly larger diameters were better and the fourth power of the diameter of the preformed armor rods has a linear relationship with the grip force.

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Unraveling quench dynamics and real-time continuous detection in HTS tapes through distributed fiber optic sensing

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SUPERCONDUCTOR SCIENCE & TECHNOLOGY 2023年第12期36卷 125007-125007页

作者： Yang, Taolue Wang, Xingzhe Lanzhou Univ Minist Educ Coll Civil Engn & Mech MoEKey Lab Special Funct Mat & Struct DesignKey Lanzhou 730000 Peoples R China China Southern Power Grid Technol Co Ltd Guangzhou 510080 Peoples R China

High-temperature superconducting (HTS) tapes, coils, and magnets often experiences intricate quench instabilities and failures during high current-carrying operations, posing challenges to their practical applications. This study addresses the need for a measurement approach capable of monitoring multi-field signals in superconducting structures within cryogenic and extreme electromagnetic environments. We explore the application of distributed fiber optic sensing (DFOS) technology, specifically employing the optical frequency domain reflectometry scheme, which offers distinct advantages over traditional point-type electrical testing methods, particularly for superconducting materials and magnets. In this experimental study, we continuously track the quench evolution process in superconducting tapes using both bonded and stress-free fibers for real-time monitoring. A comprehensive analysis of the acquired temperature and thermoelastic strain profiles provides essential insights into the dynamic behavior of quench events. The findings demonstrate the effectiveness of DFOS in identifying and characterizing the onset and propagation of quenches. By arranging bonded and stress-free fibers in parallel on the HTS tape's surface, we successfully decouple the effects of strain-temperature cross-sensitivity, enabling the extraction of temperature and train profiles. The bonded fiber optic sensor demonstrates rapid sensitivity to the thermally quenched events. Temporal derivatives of voltage and thermal strain exhibit characteristic plateaus and slope changes during quenches, respectively. The voltage rate displays two plateaus corresponding to superconducting-to-normal transitions, while strain rates exhibit potential as criteria for identifying quench events in HTS materials. Moreover, DFOS outperforms traditional terminal average voltage measurement, capturing quench evolution tails from the initial point of quench until the complete transition of the segment into the norm

关键词： HTS tapes quench detection distributed fiber optic sensing OFDR strain and temperature decouple

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Research on the test method of new smart meter based on embedded operating system 2020

Research on the test method of new smart meter based on embe...

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2020 International Conference on Aviation Safety and Information Technology, ICASIT 2020

作者： Wang, Zhiqiang Liang, Zhaoqing Qu, Shengbo Fu, Qingqin Liu, Jia Beijing Smartchip Microelectronics Technology Co. Ltd. Key Lab of Power Grid Design and Analysis State Grid Corporation of China Beijing China

ISBN: (纸本)9781450375764

In order to realize the separation of metering function and non-metering function, the smart meter is divided into the metering module, extended module and management module. Furthermore, the management module of the new smart meter accomplishes the hardware and software decoupling by introducing the embedded operating system (EOS). This paper proposes some test method to verify the efficiency of the new smart meter. The result has indicated that the new smart meter based on EOS can achieve superior over the traditional smart meter in term of the real-time performance, security and robustness. © 2020 ACM.

关键词： Testing

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Dynamic self-test scheme and authentication protocol for improving robustness of strong PUF

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MICROELECTRONICS JOURNAL 2023年 139卷

作者： Li, Yan Yang, Weifeng Li, Jiang Yuan, Yanfang Zhang, Hu Wang, Fengdi Cui, Yijun Beijing Smart Chip Microelect Technol Co Ltd State Grid Key Lab Power Ind Chip Design & Anal Te Beijing Peoples R China Nanjing Univ Aeronaut & Astronaut Nanjing 211106 Peoples R China

In the realm of IoT applications, where resources are limited, physical unclonable functions (PUFs) have emerged as a promising encryption strategy due to their lightweight and high-security. While several PUFs have been proposed, there is still a need to balance low-cost and high security given the constraints of hardware resources. This paper presents a PUF design based on sub-threshold current arrays that offers high resource utilization. To improve the robustness of PUF response, a dynamic control and self-test scheme is proposed. Additionally, a high-efficiency authentication protocol is developed to enhance the utilization of CRPs. Even if an unstable response is generated, the proposed protocol considers it to be authenticated successfully as long as the degree of stability of the response is within a specific range. The PUF circuit occupies only 377.4 nm2 and achieves good uniqueness and stability with a bit error rate (BER) of 0.45% per 10 degrees C over a temperature range of -40 degrees C to 80 degrees C.

关键词： Sub-threshold current array Physical unclonable function Hardware security Authentication protocol

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A-CS: Adaptive Compressive Data Gathering for Chain-type Wireless Sensor Networks 4

A-CS: Adaptive Compressive Data Gathering for Chain-type Wir...

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2022 4th International Conference on Electronic Engineering and Informatics, EEI 2022

作者： Jia, Qiang Zhang, Yiyi Guo, Peng Zhang, Kui Liu, Jiang State Grid Key Laboratory of Power Industrial Chip Design and Analysis Technology Beijing Smart-Chip Microelectronics Technology Co. Ltd. Beijing China Huazhong University of Science and Technology Wuhan China Pentair Group Netherlands Shenzhen Miaoyan Technology Co. Ltd. Shenzhen China

ISBN: (纸本)9783800759231

Compressive Sensing has been validated as an efficient way for data gathering in chain-type wireless sensor networks (WSNs). Given the sparsity of the sensor nodes’ raw data, each sensor node just needs to send a constant size of data during the multi-hop data gathering, instead of relaying increasing size of data as in traditional data gathering works. However, we notice that the sparsity of raw data in event-involved local region may not be the same as that in the other usual region, which gives us hint that existing compressive sensing based on uniform sparsity of data actually can be improved. In this paper, we propose an adaptive compressive data gathering method A-CS for chain-type wireless sensor networks. Meanwhile, we design an ultra-lightweight localized sparsity variation detection mechanism for determining the event-involved region. Numerous simulation has been conducted, showing the efficiency of the proposed A-CS method. © VDE VERLAG GMBH ∙ Berlin ∙ Offenbach.

关键词： Compressed sensing

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A 433/2400 MHz dual-band frequency synthesizer with glitch-free phase-interpolated frequency divider and hybrid post-synthesizer

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MICROELECTRONICS JOURNAL 2021年 116卷 105158-105158页

作者： Tang, Xiaoke Zhao, Xu Hu, Ang Liu, Dongsheng Jin, Zirui Beijing Smart Chip Microelect Technol Co Ltd State Grid Key Lab Power Ind Chip Design & Anal T Beijing Peoples R China Huazhong Univ Sci & Technol Sch Opt & Elect Informat Wuhan 430074 Peoples R China

A three-stage low phase noise cascaded phase locked loop (PLL) with reference quadrupler and phase interpolated (PI) frequency divider is presented in this paper. The first stage consists of a frequency doubler and an injection locked (IL) loop. By increasing the reference frequency from 50 MHz to 200 MHz, the maximum loop division ratio is deduced, yielding to 12 dB in-band noise transfer gain suppression and larger loop bandwidth. The second stage is a fractional-N PLL. In order to mitigating the effect of quantization noise in fractional N model, a double-orthogonal PI frequency divider is utilized. The division ratio step is reduced from 1 to 1/32, leading to 30 dB quantization noise suppression. The third stage is a hybrid charge-pump (CP) and sub-sampling PLL (SSPLL). By utilizing this hybrid structure, the third-stage output phase noise is dominated by the output clock of the second stage. The PLL is designed and simulated in 65 nm CMOS process. At 2.4 GHz, the spot phase noise are-100 and-114 dBc/Hz at 10 kHz and 1 MHz offsets respectively and the power consumption is 12 mW.

关键词： Phase lock loops (PLL) Injection locked Injection Phase interpolator Frequency synthesizer (FS)

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Structure and regional optimization of a phase change material Trombe wall system

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ENERGY 2024年 305卷

作者： Zhou, Yaping Zhu, Jiangtian Zhang, Yuan Zhou, Xinli Sun, Xiaoqin Changsha Univ Sci & Technol Sch Energy & Power Engn Changsha 410114 Hunan Peoples R China China Mobile Design Inst Co Ltd Hunan Branch Changsha 410003 Peoples R China Changsha Univ Sci & Technol State Key Lab Disaster Prevent & Reduct Power Grid Changsha 410114 Hunan Peoples R China

Trombe walls (TW) have been an effective passive solar technology for enhancing building energy efficiency. Considering the thermal storage and regulation capabilities of phase change materials (PCM) in solar energy utilization, TW with PCM (PCMTW) were designed and optimized to further improve building energy performance. This study investigated the combined effects of PCM phase change temperature, PCM location and ventilation strategies on a single-layer PCMTW. Moreover, a novel double-layer PCMTW was proposed and evaluated across various climate regions of China in consideration of the effect of PCM phase change temperature combinations. Results show that the single-layer PCMTW with PCM22 placed next to inner surface and ventilation achieved the lowest annual energy consumption. The selection of PCM phase change temperature was crucial for various climatic conditions. Compared to the traditional building, the highest heating energy-saving was 118.16 kWh/m 2 achieved in Changchun with PCM22 + 28, and the highest cooling energy-saving was 45.71 kWh/m 2 achieved in Haikou with PCM25 + 28. Additionally, the double-layer PCMTW was recommended for climate regions where the daily average temperature and the daily average solar emissivity were 20 - 25 degrees C and below 4 kWh/m 2 in summer, and below 10 degrees C and 2 - 6 kWh/m 2 in winter.

关键词： Building sector Trombe wall Phase change material Energy saving Chinese climate

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design and characterization of novel doped heterostructured electromagnetic shielding packaging materials for Current sensor chip applications

Design and characterization of novel doped heterostructured ...

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International Conference on (ICEPT) Electronic Packaging Technology

作者： Haichao Huang Shuaipeng Wang Yanning Chen Zhen Fu Yongfu Li Xiping Jiang State Grid Key Laboratory of Power Industrial Chip Design and Analysis Technology Beijing Smart-Chip Microelectronics Technology Co. Ltd. Beijing China Beijing Smart-Chip Microelectronics Technology Co. Ltd. Beijing China State Grid Chongqing Electric Power Company Electric Power Research Institute. Chongqing China

Electromagnetic radiation not only disrupt the use of equipment such as sensors, electronic components and precision instruments and affects their normal operation, but also leads to the leakage of important data and even reduces their reliability. It is still challenging to significantly improve the anti-electromagnetic interference performance from the chip packaging material level. Doped polyaniline (PANI) is considered as one of the most potent electromagnetic shielding materials as its easy synthesis, stable performance, unique chemical and electromagnetic *** address the technical challenges of chip anti-interference in complex electromagnetic environment and make full use of the advantages of doped PANI in electromagnetic shielding, this thesis uses doped PANI, carbon fiber, metal particles, etc. to prepare heterogeneous structure composite electromagnetic shielding packaging materials. Through the modification of the material and the construction of the shielding structure, the influence of the content of functional components, the size and structure of the reflective cavity on its electromagnetic properties is systematically studied, and the mechanism of the regulation of the electromagnetic shielding performance of the material is revealed. A series of CF/PANI heterogeneous structure composite electromagnetic shielding materials were obtained by in situ polymerization of carbon fiber surface coated with PANI, through optimization of components, structure and properties. Based on the excellent electrical properties of PANI and the characteristic of no electromagnetic loss, the reflective layer is constructed inside the material, and the effects of carbon fiber and metal particle content and morphology on the conductivity and dielectric behavior of CF/PANI are systematically investigated to enhance the dielectric loss and absorption loss of the material and improve the electromagnetic shielding effectiveness of the material through multiple reflect

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An intelligent measuring device and its function realization method for deepening application in substation 6

An intelligent measuring device and its function realization...

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6th IEEE Advanced Information Technology, Electronic and Automation Control Conference (IEEE IAEAC)

作者： Du, Jun Fan, Lin Cui, Yongxu Liang, Hua Liu, Yongfu Beijing Smart Chip Microelect Technol Co Ltd State Grid Key Lab Power Ind Chip Design & Anal T Beijing 100192 Peoples R China Beijing Smart Chip Microelect Technol Co Ltd Beijing Engn Res Ctr High Reliabil IC Power Ind G Beijing 100192 Peoples R China

ISBN: (数字)9781665458641

ISBN: (纸本)9781665458641

This thesis focuses on the intelligent measuring device for further application of power supply district , which realizes an analysis method of meter measurement error in the electricity meter box and an efficient electrical topology identification scheme in power supply district. Through the meter search, reading and measurement functions of the switches , the corresponding relationship between the total meter and the sub meter in the meter box is realized, and a matrix equation related to the measurement value and the abnormal coefficient is established. The analysis of meter inaccuracy or power theft behavior is supported by solving the abnormal coefficient of each sub meter. In view of the efficiency of electrical topology identification, a voltage distortion and characteristic current identification scheme is proposed to realize the rapid identification of sub nodes in the substation area without the archives of the terminal.

关键词： Topology identification Distorted voltage Characteristic current Measure error analyze

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Construction and mechanism analysis of flame-retardant, energy-storage and transparent bio-based composites based on natural cellulose template

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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES 2024年第Part1期263卷 130317页

作者： Li, Mixue Li, Xu Xu, Kai Qin, Ao Yan, Chentao Xu, Yue Shan, Depeng Wang, Jinlong Xu, Miaojun Li, Xiaoli Li, Bin Liu, Lubin Northeast Forestry Univ Coll Chem Chem Engn & Resource Utilizat Heilongjiang Key Lab Mol Design & Preparat Flame R Harbin 150040 Peoples R China Northeast Forestry Univ Key Lab Forest Plant Ecol Minist Educ Harbin 150040 Peoples R China State Grid Heilongjiang Elect Power Co Ltd Harbin 150040 Peoples R China

With the proposal of sustainable development strategy, bio-based energy storage transparent wood (TW) has shown broad application value in green buildings, cold chain transportation, and optoelectronic device fields. However, its application in most fields is limited due to its own flammability. In this study, epoxy resin, triethyl phosphate (TEP) and polyethylene glycol (PEG) were introduced into delignified balsa wood template by vacuum pressure impregnation, and bio-based TW/PEG/TEP integrating flame retardant, high strength and phase -change energy -storage performance was prepared. TW/PEG composites have no leakage during phase change process and their transparency is up to 95 %. Compared with TW/PEG, the shielding effect of char layer and the inhibition effect in condensed and gas phase significantly decrease the total heat release of TW/PEG/TEP. TW/PEG/ TEP biocomposites still maintained a high enthalpy of phase change and a low peak melting temperature, which was conducive to its application around the area of low temperature phase change energy storage. In addition, the tensile strength of TW/PEG/TEP was nearly 4 times higher than that of DW, and its toughness was obviously enhanced. TW/PEG/TEP biocomposites conformed to the current concept of energy -saving and green development. It has the potential to replace traditional petrochemical -based materials and shows excellent application prospects in emerging fields.

关键词： Transparent wood Fire safety Phase change energy storage

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