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Plug-in Gate-loop Compensators for Series-connected IGBT Drivers in a Solid-state Fault Current Limiter

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 165-174页

作者： Rui Wang yu chen Jing chen Lin Liang Li peng School of Electrical and Electronic Engineering Huazhong University of Science and TechnologyWuhan 430074China

A solid-state fault current limiter(SSFCL)is the key protective equipment in a direct current distribution network.In order to meet the high voltage requirements and reduce costs,implementing a SSFCL based on series-connected insulated gate bipolar transistors(IGBTs)is a promising approach.However,voltage unbalancing of IGBTs would be introduced if the gateloops of the IGBTs are non-identical.In this paper,a plug-in gate-loop compensator with discrete gate voltage feedback and pulsewidth current compensation is proposed.The main merits are:1)with the plug-in structure,the extra current sources only provide small power to fine-tune the gate-loop without affecting the functions provided by the commercial IGBT gate driver;2)the gate-emitter voltages of IGBTs are compared with the preset thresholds to obtain control criterion,and the pulsewidths of the current sources are controlled for gate-loop compensation,thus both analog-digital and digital-analog converters are avoided;3)the control law is easy to implement in FPGA,and is robust to voltage variation of power-loops.With the proposed compensator,the voltage unbalancing is alleviated immediately at the present switching cycle,and further eliminated cycle-by-cycle during the current limitation process.Experimental results verify the feasibility of the proposed compensator.

关键词： Current limitation direct current distribution network insulated gate bipolar transistors(IGBTs) voltage balancing

Inertial Proximal ADMM for Separable Multi-Block Convex Optimizations and Compressive Affine Phase Retrieval

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1459-1496页

作者： peng LI Wen Gu chen Qi yu SUN School of Mathematics and Statistics Gansu Key Laboratory of Applied Mathematics and Complex SystemsLanzhou UniversityLanzhou 730000P.R.China Graduate School China Academy of Engineering PhysicsBeijing 100088P.R.China Institute of Applied Physics and Computational Mathematics Beijing 100088P.R.China Department of Mathematics University of Central FloridaOrlandoFL 32816USA

Separable multi-block convex optimization problem appears in many mathematical and engineering fields.In the first part of this paper,we propose an inertial proximal ADMM to solve a linearly constrained separable multi-block convex optimization problem,and we show that the proposed inertial proximal ADMM has global convergence under mild assumptions on the regularization matrices.Affine phase retrieval arises in holography,data separation and phaseless sampling,and it is also considered as a nonhomogeneous version of phase retrieval,which has received considerable attention in recent years.Inspired by convex relaxation of vector sparsity and matrix rank in compressive sensing and by phase lifting in phase retrieval,in the second part of this paper,we introduce a compressive affine phase retrieval via lifting approach to connect affine phase retrieval with multi-block convex optimization,and then based on the proposed inertial proximal ADMM for 3-block convex optimization,we propose an algorithm to recover sparse real signals from their(noisy)affine quadratic measurements.Our numerical simulations show that the proposed algorithm has satisfactory performance for affine phase retrieval of sparse real signals.

关键词： Inertial proximal ADMM separable multi-block convex optimization affine phase retrieval

A Visualization Analysis of Medical and Prevention Fusion Research in China via CiteSpace

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China CDC weekly 2023年第23期5卷 519-524,I0001,I0002页

作者： chen Jin Sijing Tu yu Qian Xiaoyu chen Zhiyi peng Xiaohe Wang School of Public Health Hangzhou Normal UniversityHangzhou CityZhejiang ProvinceChina School of Public Health and Management Guangxi University of Chinese MedicineNanning CityGuangxi Zhuang Autonomous RegionChina

Since the 1990s,the acceleration of population aging has led to an increased prevalence of chronic diseases and enhanced public health awareness.Numerous countries have proposed healthcare reforms,with a focus on creating an“integrated care”model that aims to improve the quality of medical services and reduce costs(1–2).In 2008,the World Health Organization(WHO)put forward the concept of Integrated Delivery Systems(IDS),advocating for continuous,timely and integrated medical services.

关键词： services CiteSpace acceleration

Design and modeling of a novel soft parallel robot driven by endoskeleton pneumatic artificial muscles

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Frontiers of Mechanical Engineering 2022年第2期17卷 71-84页

作者： peng chen Tingwen yuAN Yi yu yuwang LIU State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China University of Chinese Academy of Sciences Beijing 100049China School of Mechanical Engineering Northeastern UniversityShenyang 110000China

Owing to their inherent great flexibility, good compliance, excellent adaptability, and safe interactivity, soft robots have shown great application potential. The advantages of light weight, high efficiency, non-polluting characteristic, and environmental adaptability provide pneumatic soft robots an important position in the field of soft robots. In this paper, a soft robot with 10 soft modules, comprising three uniformly distributed endoskeleton pneumatic artificial muscles, was developed. The robot can achieve flexible motion in 3D space. A novel kinematic modeling method for variable-curvature soft robots based on the minimum energy method was investigated, which can accurately and efficiently analyze forward and inverse kinematics. Experiments show that the robot can be controlled to move to the desired position based on the proposed model. The prototype and modeling method can provide a new perspective for soft robot design, modeling, and control.

关键词： pneumatic artificial muscles soft robot modeling approach principle of virtual work external load

Research on low carbon emission optimization operation technology of natural gas pipeline under multi-energy structure

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Petroleum Science 2022年第6期19卷 3046-3058页

作者： En-Bin Liu Yong peng Shan-Bi peng Bin yu Qi-Kun chen Petroleum Engineering School Southwest Petroleum UniversityChengdu610500China School of Civil Engineering and Geomatics Southwest Petroleum UniversityChengdu610500China China Petroleum Pipeline Engineering Corporation Hebei065000China School of Engineering Cardiff UniversityCardiffCF243AAUK

In order to reduce the carbon emissions of natural gas pipelines,based on the background of different energy structures,this paper proposes a general low carbon and low consumption operation model of natural gas pipelines,which is used to fine calculate the carbon emissions and energy consumption of natural gas pipeline.In this paper,an improved particle swarm optimization(NHPSO-JTVAC)algorithm is used to solve the model and the optimal scheduling scheme is given.Taking a parallel pipeline located in western China as an example,the case is analyzed.The results show that after optimization,under the existing energy types,the pipeline system can reduce 31.14%of carbon emissions,and after introducing part of new energy,the pipeline system can reduce 34.02%of carbon emissions,but the energy consumption has increased.

关键词： Natural gas Pipeline optimization NHPSO-JTVAC algorithm Carbon emission New energy

Beamforming and fronthaul compression design for intelligent reflecting surface aided cloud radio access networks

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Frontiers of Information Technology & Electronic Engineering 2022年第1期23卷 31-46页

作者： yu ZHANG Xuelu WU Hong peng Caijun ZHONG Xiaoming chen College of Information Engineering Zhejiang University of TechnologyHangzhou310023China National Mobile Communications Research Laboratory Southeast UniversityNanjing210096China College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China

Owing to the inherent central information processing and resource management ability,the cloud radio access network(C-RAN)is a promising network structure for an intelligent and simplified sixth-generation(6G)wireless network.Nevertheless,to further enhance the capacity and coverage,more radio remote heads(RRHs)as well as high-fidelity and low-latency fronthaul links are required,which may lead to high implementation cost.To address this issue,we propose to exploit the intelligent reflecting surface(IRS)as an alternative way to enhance the C-RAN,which is a low-cost and energy-efficient option.Specifically,we consider the uplink transmission where multi-antenna users communicate with the baseband unit(BBU)pool through multi-antenna RRHs and multiple IRSs are deployed between the users and RRHs.RRHs can conduct either point-to-point(P2P)compression or Wyner-Ziv coding to compress the received signals,which are then forwarded to the BBU pool through fronthaul links.We investigate the joint design and optimization of user transmit beamformers,IRS passive beamformers,and fronthaul compression noise covariance matrices to maximize the uplink sum rate subject to fronthaul capacity constraints under P2P compression and Wyner-Ziv coding.By exploiting the Arimoto-Blahut algorithm and semi-definite relaxation(SDR),we propose a successive convex approximation approach to solve non-convex problems,and two iterative algorithms corresponding to P2P compression and Wyner-Ziv coding are provided.Numerical results verify the performance gain brought about by deploying IRS in C-RAN and the superiority of the proposed joint design.

关键词： Cloud radio access network(C-RAN) Intelligent reflecting surface(IRS) Transmit beamforming Fronthaul compression

A deep reinforcement learning(DRL)based approach for well-testing interpretation to evaluate reservoir parameters

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Petroleum Science 2022年第1期19卷 264-278页

作者： peng Dong Zhi-Ming chen Xin-Wei Liao Wei yu State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing(CUP)Beijing102249China University of Texas at Austin Austin78731TexasUSA

Parameter inversions in oil/gas reservoirs based on well test interpretations are of great significance in oil/gas industry.Automatic well test interpretations based on artificial intelligence are the most promising to solve the problem of non-unique solution.In this work,a new deep reinforcement learning(DRL)based approach is proposed for automatic curve matching for well test interpretation,by using the double deep Q-network(DDQN).The DDQN algorithms are applied to train agents for automatic parameter tuning in three conventional well-testing models.In addition,to alleviate the dimensional disaster problem of parameter space,an asynchronous parameter adjustment strategy is used to train the agent.Finally,field applications are carried out by using the new DRL approaches.Results show that step number required for the DDQN to complete the curve matching is the least among,when comparing the naive deep Q-network(naive DQN)and deep Q-network(DQN).We also show that DDQN can improve the robustness of curve matching in comparison with supervised machine learning algorithms.Using DDQN algorithm to perform 100 curve matching tests on three traditional well test models,the results show that the mean relative error of the parameters is 7.58%for the homogeneous model,10.66%for the radial composite model,and 12.79%for the dual porosity model.In the actual field application,it is found that a good curve fitting can be obtained with only 30 steps of parameter adjustment.

关键词： Well testing Deep reinforcement learning Automatic interpretation Parameter evaluation

Design and Analysis of a 2-DOF Actuator with Variable Stiffness Based on Leaf Springs

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Journal of Bionic Engineering 2022年第5期19卷 1392-1404页

作者： ShangKui Yang peng chen DongQi Wang Yi yu yuWang Liu State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110000China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110000China Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education School of Mechanical Engineering Tianjin UniversityTianjin 300192China University of Chinese Academy of Sciences Beijing 100049China

Variable Stiffness Actuator(VSA)is the core mechanism to achieve physical human–robot interaction,which is an inevitable development trend in robotic.The existing variable stiffness actuators are basically single degree-of-freedom(DOF)rotating joints,which are achieving multi-DOF motion by cascades and resulting in complex robot body structures.In this paper,an integrated 2-DOF actuator with variable stiffness is proposed,which could be used for bionic wrist joints or shoulder joints.The 2-DOF motion is coupling in one universal joint,which is different from the way of single DOF actuators cascade.Based on the 2-DOF orthogonal motion generated by the spherical wrist parallel mechanism,the stiffness could be adjusted by varying the effective length of the springs,which is uniformly distributed in the variable stiffness unit.The variable stiffness principle,the model design,and theoretical analysis of the VSA are discussed in this work.The independence of adjusting the equilibrium position and stiffness of the actuator is validated by experiments.The results show that the measured actuator characteristics are sufficiently matched the theoretical values.In the future,VSA could be used in biped robot or robotic arm,ensuring the safety of human–robot interaction.

关键词： Physical human-robot interaction 2-DOF Bionic wrist joints Variable stiffness actuator Leaf spring

Asymptomatic neurosyphilis may need early intervention in people living with HIV

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Chinese Medical Journal 2020年第23期133卷 2877-2879页

作者： Hong-Jie chen Tao yu Jie peng State Key Laboratory of Organ Failure Research Guangdong Provincial Key Laboratory of Viral Hepatitis ResearchDepartment of Infectious DiseasesNanfang HospitalSouthern Medical UniversityGuangzhouGuangdong 510515China

Syphilis is a sexually transmitted infection caused by the spirochete Treponema pallidum(T.pallidum)and is of global and historic significance.People living with HIV(PLWH)infection are frequently coinfected with syphilis,because of the overlapping modes of pathogen acquisition.Neurosyphilis can occur at any stage of syphilis infection,and PLWH are at a greater risk of developing neurosyphilis in early and late latent syphilis,including asymptomatic central nervous system(CNS)infection than those without HIV infection.Some patients with neurosyphilis present neurological manifestations such as meningitis,stroke,cranial nerve dysfunction,auditory or ophthalmic abnormalities,and acute changes in mental status.However,some neurosyphilis cases in PLWH lack signs or symptoms of CNS infection.Asymptomatic neurosyphilis is diagnosed in the absence of neurological signs or symptoms and can only be detected in the presence of cerebrospinal fluid(CSF)abnormalities indicative of CNS infection,including mononuclear pleocytosis,increased protein concentration,and/or a reactive CSF venereal disease research laboratory(VDRL)assay.This has raised concerns that a persistent reservoir of T.pallidum although asymptomatic in the CNS,may result in treatment failure and neurological sequelae in PLWH.Neurosyphilis might lead to cranial nerve palsies,syphilitic meningitis,general paresis,and tabes dorsalis even several years after infection.Thus,early intervention may be needed for asymptomatic neurosyphilis in PLWH.

关键词： Asymptomatic auditory acute