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arXiv 2022年

作者： Li, Yang Wang, Ruinong Li, Yuanzheng Zhang, Meng Long, Chao The Key Laboratory of Modern Power System Simulation Control and Renewable Energy Technology Ministry of Education Northeast Electric Power University Jilin132012 China The State Grid Jilin Electric Power Co. Ltd Jilin Power Supply Company Chuanying District Jilin132001 China The School of Artificial Intelligence and Automation Huazhong University of Science and Technology Wuhan430074 China The School of National Key Laboratory of Science and Technology Vessel Integrated Power System Naval University of Engineering Wuhan430033 China The School of Water Energy and Environment Cranfield University United Kingdom

In a modern power system with an increasing proportion of renewable energy, wind power prediction is crucial to the arrangement of power grid dispatching plans due to the volatility of wind power. However, traditional centralized forecasting methods raise concerns regarding data privacy-preserving and data islands problem. To handle the data privacy and openness, we propose a forecasting scheme that combines federated learning and deep reinforcement learning (DRL) for ultra-short-term wind power forecasting, called federated deep reinforcement learning (FedDRL). Firstly, this paper uses the deep deterministic policy gradient (DDPG) algorithm as the basic forecasting model to improve prediction accuracy. Secondly, we integrate the DDPG forecasting model into the framework of federated learning. The designed FedDRL can obtain an accurate prediction model in a decentralized way by sharing model parameters instead of sharing private data which can avoid sensitive privacy issues. The simulation results show that the proposed FedDRL outperforms the traditional prediction methods in terms of forecasting accuracy. More importantly, while ensuring the forecasting performance, FedDRL can effectively protect the data privacy and relieve the communication pressure compared with the traditional centralized forecasting method. In addition, a simulation with different federated learning parameters is conducted to confirm the robustness of the proposed scheme. Copyright © 2022, The Authors. All rights reserved.

关键词： Electric load dispatching

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Broadband power Amplifiers Behavioral Modeling Method Based on Instantaneous Input power 3

Broadband Power Amplifiers Behavioral Modeling Method Based ...

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3rd IEEE International Conference on Electronic Information and Communication technology, ICEICT 2020

作者： Li, Wei Bian, Hongwei Meng, Jin Zhang, Jiahao Li, Yi National Key Laboratory of Science and Technology on Vessel Integrated Power System Wuhan China Faculty of Electrical Engineering Naval University of Engineering Wuhan China

ISBN: (纸本)9781728190457

This paper presents a novel Augmented Memory Polynomial (AMP) model for the broadband radio frequency high power amplifiers behavioral modeling and digital predistortion. The proposed model consists of a weighted memoryless sub model and a weighted memory sub model. The weighted memoryless sub model involving a weighting, polynomial error signal, and de-weighting parts is used for predicting the strong static nonlinear behaviors of the power amplifiers. The weighted memory sub model is used for the dynamic memory nonlinearity by introducing an instantaneous power dependent weight function into the static and dynamic terms of the conventional memory polynomial (CMP) model. The performance of the proposed model is assessed in terms of in-band and out-of-band errors, such as normalized mean square error (NSME) and adjacent channel power ratio (ACPR). Compared with the CMP, the weighted memory polynomial (WMP) is complex in computation due to the numbers of model coefficient. Furthermore, the proposed method is applied to the digital predistortion so as to cancel the nonlinearity of the power amplifier. The experimental results show that the proposed for modelling the power amplifier and applying the digital predistortion is feasible and effective because it can result in up to 10dB improvement in the ACPR for the same number of coefficients. © 2020 IEEE.

关键词： power amplifiers

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PCG: Mitigating Conflict-based Cache Side-channel Attacks with Prefetching

arXiv

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arXiv 2024年

作者： Jiang, Fang Tong, Fei Wang, Hongyu Cheng, Xiaoyu Zhou, Zhe Ling, Ming Mao, Yuxing The School of Cyber Science and Engineering Southeast University Jiangsu Nanjing China Jiangsu Province Engineering Research Center of Security for Ubiquitous Network China The Purple Mountain Laboratories Jiangsu Nanjing China The State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Wiscom System Co. LTD China The School of Integrated Circuits Southeast University Jiangsu Nanjing China

To defend against conflict-based cache side-channel attacks, cache partitioning or remapping techniques were proposed to prevent set conflicts between different security domains or obfuscate the locations of such conflicts. But such techniques complicate cache design and may result in significant performance penalties. Therefore, there have been lightweight prefetching-based schemes proposed to introduce noise to confuse attackers’ observation. However, we have validated experimentally that relying on prefetching to only introduce noise is insufficient, as attackers can still reliably distinguish the victim’s cache accesses. This paper proposes a novel prefetching-based scheme, called PCG. It combines adding victim-irrelevant cache occupancy changes and reducing victim-relevant cache occupancy changes to disrupt attackers by generating noisy and indistinguishable cache access patterns. Additionally, PCG can either work independently or seamlessly be integrated with most of the commonly used prefetchers. We have implemented and evaluated PCG in both gem5 and the open-source RISC-V core BOOMv3. The evaluation results show the PCG’s robust security superior to the existing solutions, while without resulting in significant performance degradation. According to the evaluation based on the SPEC CPU 2017 benchmark suite, PCG even shows an average performance improvement of about 1.64%. Moreover, it incurs only 1.26% overhead on hardware resource consumption. Copyright © 2024, The Authors. All rights reserved.

关键词： Side channel attack

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A High Step-down DC-DC Converter with Matrix-Transformer and Wide Voltage Gain for Vehicle power Supply Applications 22

A High Step-down DC-DC Converter with Matrix-Transformer and...

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22nd International Conference on Electrical Machines and systems, ICEMS 2019

作者： Xu, Xiaohui Zhang, Yinghui Zhu, Lei Yu, Hu Zhang, Yanfeng Wu, Hongfei Integrated Power System Technology Laboratory Science and Technology on Ship WuHan China Nanjing University of Aeronauticss and Astronautics Nanjing China

ISBN: (纸本)9781728133980

A two-stage high step-down DC-DC converter with matrix-transformer is presented for vehicle power supply applications. Wide voltage gain is achieved by the front-end Boost converter and down-stream phase-shifted full-bridge converter. With the novel two-stage structure, the input voltage range of the down-stream full-bridge converter is narrowed significantly, which helps to reduce the current stress of primary switches and the voltage stress of the secondary switches. Devices with better performances can be chosen and high efficiency power conversion is achieved with the presented topology. Furthermore, the matrix-transformer is used in full-bridge converter to handle the large output current, which is beneficial for simplifying the design and processing of the transformer. Meanwhile, the current sharing of transformer windings will not be considered. Operation principles and characteristics of this converter are analyzed in detail. Experimental results are provided to evaluate the effectiveness of the presented solutions. © 2019 IEEE.

关键词： Vehicles

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A Modular Multilevel Converter with integrated Composite Energy Storage for ship MVDC Electric Propulsion system

A Modular Multilevel Converter with Integrated Composite Ene...

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International Conference on power Electronics and Motion Control (IPEMC)

作者： Wenfeng Long Nianzhou Liu Kui Wang Xiaohui Xu Zedong Zheng Yongdong Li Science and Technology on Ship Integrated Power System Technology Laboratory Wuhan China China State Key Lab. of Power System Tsinghua University Beijing China

ISBN: (数字)9781728153018

ISBN: (纸本)9781728153025

In order to satisfy the demands of ship high-power electric propulsion system and energy storage system of a medium voltage direct current (MVDC) based ship integrated power system (IPS), a modular multilevel converter with integrated composite energy storage (MMC-ICES) is proposed in this paper. In order to pursue both fast power response and longtime power supply, both batteries and super-capacitors are integrated into the MMC to form a composite energy storage. Therefore, it can not only compensate the pulse power of high-energy equipment in a ship, solve the low-frequency voltage fluctuation problem of sub-module capacitors when the MMC drives a propulsion motor under low speed high torque condition, but also provide emergency power supply under ship grid fault condition. The decoupled control method is discussed in detail and verified by simulation results in this paper.

关键词： Multilevel converters Voltage fluctuations Torque Simulation Capacitors Propulsion Marine vehicles

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Threshold Voltage Stability Enhancing technology for p-GaN HEMTs Using Hybrid Gate Structure

IEEE Electron Device Letters

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IEEE Electron Device Letters 2022年 1-1页

作者： Zhang, Chi Li, Mingfei Li, Sheng Liu, Siyang Wang, Denggui Lu, Weihao Ma, Yanfeng Liu, Mengli Wei, Jiaxing Zhang, Long Zhou, Jianjun Bai, Song Sun, Weifeng National ASIC System Engineering Research Centre Southeast University Nanjing China Science and Technology on Monolithic Integrated Circuits and Modules Laboratory Nanjing Electronic Devices Institute Nanjing China State Key Laboratory of Wide-Bandgap Semiconductor Power Electronic Devices Nanjing Electronic Devices Institute Nanjing China

A novel hybrid gate p-GaN power high-electron mobility transistor (Hyb-HEMT) technology is proposed in this work to effectively enhance threshold voltage (Vth) stability without significant gate leakage current (Igss) degradation. In this device concept, gate structure consists of spaced ohmic-type p-GaN metal dots and Schottky-type p-GaN metal. Charge storage effect can be alleviated through a free-carrier “discharge path” induced by ohmic-type p-GaN region, thus enhancing the Vth stability. The surrounding geometry distribution of Schottky-type p-GaN metal can take full advantage of depletion region, ensuring a relatively low Igss. It is experimentally demonstrated that hybrid gate structure can successfully suppress Vth shift within only 0.03V under 1200s DC drain/gate bias stress and the activation energy (EA) of proposed Hyb-HEMT is only 0.59eV, which indicates Hyb-HEMT owns shallower traps, leading to easier discharge of the induced stored charges. Meanwhile, experimental results and the mix-mode simulation prove that no carrier injection or trapping effect occurs in p-GaN layer after repetitive reverse freewheeling stress for the Hyb-HEMT device. IEEE

关键词： Threshold voltage

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A Narrow-strip Broadband Microstrip Patch Antenna Based on Conducting Block Transition Fed

A Narrow-strip Broadband Microstrip Patch Antenna Based on C...

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IEEE Information technology, Networking, Electronic and Automation Control Conference

作者： Qiliang Wang Kang Luo Yi Li Jin Meng Fangmin He National Key Laboratory of Science and Technology on Vessel Integrated Power System

ISBN: (数字)9781728143903

ISBN: (纸本)9781728143910

In this paper, a narrow-strip broadband microstrip antenna based on conducting block transition is designed. In order to meet narrow-strip dimensions (width is less than 0.22λ), a feed structure combining conducting block and short probe is applied, which plays a role of transition tuning. The formulas of transmission line mode and Q factor are analyzed to guide antenna design. An impedance bandwidth of 90% (-10dB) and 56% (-16dB) at operating frequency 3.5GHz is obtained. A parametric study of the antenna is described, including the thickness of the air layer, relative position of the feed source and the dimensions of the radiating patch. The antenna without the radiating patch is constructed and studied. By analyzing the current distribution on the patch surface, a anti-symmetric cross-feed structure in the longitudinal direction of the antenna is presented, which effectively improves the cross-polarization in H-plane.

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A Predictive Method for Switching Time of Nanosecond Pulsed power system of Ohmic Loads Using SiC MOSFETs

A Predictive Method for Switching Time of Nanosecond Pulsed ...

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Workshop on Wide Bandgap power Devices and Applications in Asia (WiPDA Asia)

作者： Yifei Luo Xin Li Fei Xiao Zenan Shi Ruitian Wang Feng Xie National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an China

ISBN: (纸本)9781665448178

In this paper, a predictive method for accurately determining the switching time of nanosecond pulsed power system is proposed, which is important to evaluate and better design higher-grade pulse power system. Compared to the traditional predictive method of switching time, the ohmic loads and nonlinearity of capacitances are considered in the proposed method. In detail, the expressions of the switching time are deduced, in which, the main parasitic elements affecting the switching transient are considered. In order to verify the validity of the method, an ohmic-load double pulse circuit is established. The experimental device is a CREE SiC MOSFET module CAS325M12HM2 (1200V/325A). The predictive results of the proposed method are compared with experiments and the traditional predictive method under different voltages and currents. The comparison results show that the proposed method has a good agreement with experiments and has better predictive accuracy than the traditional method, which verifies the effectiveness and accuracy. The method of prediction the switching time of nanosecond pulsed power system of ohmic loads using SiC MOSFETs offers a theoretical reference to evaluate and improve pulse power systems.

关键词： MOSFET Silicon carbide Asia Switches Prediction methods Capacitance Pulse circuits

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High-Performance Object Detection for Optical Remote Sensing Images with Lightweight Convolutional Neural Networks 22

High-Performance Object Detection for Optical Remote Sensing...

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22nd IEEE International Conference on High Performance Computing and Communications, 18th IEEE International Conference on Smart City and 6th IEEE International Conference on Data science and systems, HPCC-SmartCity-DSS 2020

作者： Liu, Jia Liu, Renhua Ren, Kaijun Li, Xiaoyong Xiang, Jianjian Qiu, Shaohua China University of Geosciences School of Computer Science Wuhan China National University of Defense Technology College of Meteorology and Oceanography Changsha China National Key Laboratory of Science and Technology on Vessel Integrated Power System Naval University of Engineering Wuhan China

ISBN: (纸本)9781728176499

Convolutional neural network (CNN)-based object detection for optical remote sensing images has achieved higher accuracy compared with traditional detection methods with handcrafted features. However, the deep and large CNNs make it hard to be deployed in real-Time scenarios with limited computation, storage, power and bandwidth resources, for example, data processing onboard airborne, satellites and unmanned aerial vehicles for search and rescue. Therefore, in this paper we present a high-performance object detection approach for optical remote sensing images. Based on the widely used Faster R-CNN framework, we integrate state-of-The-Art lightweight CNNs as backbone to extract features, slim the heavy-head architecture of two-stage detector by reducing dimensions of features, and fine-Tune our models with NWPU VHR-10 optical remote sensing dataset. Besides, the multi-Threading for CPU and detection in batches for GPU are deployed to enhance the throughput of detectors and utilization of multi-core CPU and many-core GPU. Experiments show that our presented detection approach can significantly reduce the model size, computation complexity and detection time, while maintaining competitive accuracy. Specifically, the one with ShuffleNet-v2 and slimmed features has achieved a highest mean average precision of 94.39%, a lowest computational complexity of 18.97 Giga floating point operations, a highest detection speed of 90.10 frames per second (fps) for GPU and 3.07 fps for CPU, corresponding to speedups of 6.94X and 13.26X compared with the baseline on the benchmarked system, with a model size of 13.6 MB. Moreover, it further improves the efficiency and achieves 4.98 fps on CPU with 4 threads, and 200.24 fps on GPU with a batch size of 32. © 2020 IEEE.

关键词： Object detection

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Research on Image Enhancement and Detection Techniques for Multiple Fault Types in Insulators of power Transmission Lines

SSRN

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SSRN 2024年

作者： He, Min Qin, Liang Li, Qiang Zhu, Wanjun Deng, Xinlan Liu, Kaipei Hubei Key Laboratory of Power Equipment System Security for Integrated Energy 299 Bayi Road Wuchang District Hubei Wuhan430072 China School of Electrical Engineering and Automation Wuhan University 299 Bayi Road Wuchang District Hubei Wuhan430072 China State Grid Information Telecommunication Group Co. Ltd. Changping District Future Science and Technology City Beijing102211 China

Insulators are crucial components in power transmission lines, and their exposure to harsh environmental conditions can lead to malfunctions. The complexity of insulator inspection arises primarily from the intricate lighting and background conditions in the inspection environment. Effectively and promptly detecting the fault status of these insulators in such a complex environment is an urgent issue that needs to be *** paper addresses the challenges posed by complex lighting conditions, particularly the issues of uneven illumination in low-light and high overexposure environments. A novel adversarial network based on structure and brightness layer decomposition and fusion is designed to tackle these challenges. Through the implementation of a brightness balance loss strategy, the usability of inspection images is enhanced, resulting in an average PSNR improvement of 0.4 and an SSIM improvement of 0.29 in the enhanced ***, an improved YOLOv8-based algorithm for detecting multiple fault types in aerial images of insulators with complex backgrounds and varying fault sizes is designed. This algorithm aims to achieve rapid and accurate localization of insulators and their respective fault areas.A portion of the approach utilizes the distribu tion characteristics of insulators, combining them with an axial attention feature extraction structure to extract targets in complex backgrounds. In the subsequent feature fusion stage, a multi-scale feature fusion structure, Res-PANet, based on residual skip connections, is constructed to replace the original PANet network. This replacement aims to enhance the detection accuracy of the network in multi-object *** results indicate that the detection model, after preprocessing for complex lighting conditions, achieves a higher detection accuracy, with an average precision of 89.93%. This demonstrates a strong practical value for engineering applications. © 2024, The Authors. All rights r

关键词： Fault detection

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