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High Voltage 2023年第5期8卷 977-985页

作者： Jingang Su Liqiang Wei Peng Zhang Yan Li Yunpeng Liu electric power Research Institute of State Grid Hebei electric power Supply co.ltd. ShijiazhuangChina School of electrical and Electronic engineering North China Electric Power UniversityBaodingChina

power cable defect detection and location is a crucial aspect in power asset *** spectrum measurement can be used as a non‐destructive tool for cable *** from overheating and moisture ingress are investigated by the authors,and it is shown that multi‐type cable defects can be detected and located by this *** both electromagnetic analysis and experimental investigation,the relation between impedance variation and the dielectric permittivity is studied to reveal the method's *** approach to implement such impedance measurement online is proposed and its perspectives in terms of sensitivity is investigated by field scale *** is shown that 2%impedance variation due to defect should be *** scale tests show perspectives for online application with signal coupling through a highfrequency current transformer with focus on the differences in waveforms obtained from the impedance measurements.

关键词： power impedance defect

co-production of hydrogen, oxygen, and electricity via an integrated solar-driven system with decoupled water electrolyzer and Na-Zn ion battery

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Journal of Energy Chemistry 2025年第1期100卷 621-627页

作者： Fei Lv Longjie Liu Jiazhe Wu Pengfei Wang Lixia Pan Dengwei Jing Yubin Chen International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong University

combining water electrolysis and rechargeable battery technologies into a single system holds great promise for the co-production of hydrogen （H2） and ***,the design and development of such systems is still in its ***,an integrated hydrogen-oxygen （O2）-electricity co-production system featuring a bipolar membrane-assisted decoupled electrolyzer and a Na-Zn ion battery was established with sodium nickelhexacyanoferrate （NaNiHCF） and Zn2+/Zn as dual redox *** decoupled electrolyzer enables to produce H2and O2in different time and space with almost 100%Faradaic efficiency at 100 mA ***,the charged NaNiHCF and Zn electrodes after the electrolysis processes formed a Na-Zn ion battery,which can generate electricity with an average cell voltage of 1.75 V at 10 m A *** connecting Si photovoltaics with the modular electrochemical device,a well-matched solar driven system was built to convert the intermittent solar energy into hydrogen and electric energy with a solar to hydrogen-electricity efficiency of 16.7%,demonstrating the flexible storage and conversion of renewables.

关键词： Hydrogen electricity Decoupled water electrolyzer Na-Zn ion battery Solar energy

power System Flow Adjustment and Sample Generation Based on Deep Reinforcement Learning

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Journal of Modern power Systems and Clean Energy 2020年第6期8卷 1115-1127页

作者： Shuang Wu Wei Hu Zongxiang Lu Yujia Gu Bei Tian Hongqiang Li the Department of electrical engineering Tsinghua UniversityBeijingChina State Grid Ningxia electric power co.ltd. YinchuanChina

With the increasing complexity of power system structures and the increasing penetration of renewable energy,the number of possible power system operation modes increases *** is difficult to make manual power flow adjustments to establish an initial convergent power flow that is suitable for operation mode *** present,problems of low efficiency and long time consumption are encountered in the formulation of operation modes,resulting in a very limited number of generated operation *** this paper,we propose an intelligent power flow adjustment and generation model based on a deep network and reinforcement ***,a discriminator is trained to judge the power flow convergence,and the output of this discriminator is used to construct a value ***,the reinforcement learning method is adopted to learn a strategy for power flow convergence ***,a large number of convergent power flow samples are generated using the learned adjustment *** with the traditional flow adjustment method,the proposed method has significant advantages that the learning of the power flow adjustment strategy does not depend on the parameters of the power system ***,this strategy can be automatically learned without manual intervention,which allows a large number of different operation modes to be efficiently *** verification results of a case study show that the proposed method can independently learn a power flow adjustment strategy and generate various convergent power flows.

关键词： Deep reinforcement learning power flow adjustment system operation mode sample generation

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Equipotential shielding voltage sensor for contact measurement of transient voltage in EHV/UHV power grids

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High Voltage 2021年第2期6卷 291-301页

作者： Jianchao Zheng Bo Li Kunpeng Zha Ningming Guo Liming Wang Lab of Advanced Technology of power&electrical engineering Graduate School at ShenzhenTsinghua UniversityShenzhenChina china electric power Research Institute State Grid Corporation of ChinaBeijingChina C-epri electrical power engineering co.ltd. State Grid Corporation of ChinaBeijingChina

In this study,an equipotential shielding voltage sensor is proposed to achieve contact measurement of transient voltage in extra-high voltage(EHV)/ultra-high voltage(UHV)power *** design versions of the voltage sensor for engineering application are *** version of the sensor is designed as a miniaturized sensor for non-dis-turbing measurement of potential distribution along power electronic equipment under transient *** other version is designed for online measurement and monitoring in alternating current EHV/UHV power *** on the design parameters,the performance of the sensor is evaluated,including stability of measurement,shielding effect against the interference from adjacent objects and frequency *** order to verify the performance of this sensor,an experimental comparison between this sensor and a standard capacitive voltage divider used in high voltage laboratory was carried out and the results of comparison are *** results show that the difference of measured peak voltage between the two devices is no more than±5%,and the difference of measured time parameters between the two devices is no more than±15%.

关键词： transient power potential

Insulation structure design and electric field simulation of 500 kV isolation energy supply transformer for HVDC breaker

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High Voltage 2022年第1期7卷 185-196页

作者： Sheng Zhang Yadong Fan Qingquan Lei Jianguo Wang Yuan Liu Ting Zhan School of electrical engineering and Automation Wuhan UniversityWuhanChina Global Energy Interconnection Research Institute co. LtdBeijingChina Institute of Advanced electrical Materials Qingdao University of Science and TechnologyQingdaoChina china epri electric power engineering co.ltd. BeijingChina

The high‐voltage isolated energy supply transformer(HIET)is the key component of the HVDC breaker,which is used for energy transmission and the potential *** is a lack of research results that can meet engineering applications at home and *** design of a 500 kV HIET with dry‐type insulation is proposed,using 10 cascade connected 50 kV sub‐transformers(STs),which uses silicon rubber suitable for DC voltage as the main insulation ***‐voltage(HV)winding of ST adopts double‐shielding structure of coil semi‐conductive shielding and inner semi‐conductive shielding to improve electric field *** simulation analysis of an electric field at different insulation thicknesses and temperatures shows that the electric field decreases with an increase in thickness of *** the thickness is greater than 25 mm,the electric field reduction effect is significantly *** electric field is closely related to temperature,when at 20℃,the electric field between double‐shielding is relatively *** at 70℃,the inner shielding electric field is much higher than coil shielding,and undergoes obvious *** addition,the 500 kV HIET's electric field has been *** 500kV HIET prototype has been manufactured and passed the type test,and successfully applied to the 500 kV Zhangbei DC grid project.

关键词： winding insulation field

Dispatching Fuel-cell Hybrid electric Vehicles Toward Transportation and Energy Systems Integration

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CSEE Journal of power and Energy Systems 2023年第4期9卷 1540-1550页

作者： Dejie Zhao Ming Zhou Jianxiao Wang Tiance Zhang Gengyin Li Honghui Zhang School of electrical and Electronic engineering North China Electric Power UniversityBeijing 102206China china Automotive Technology and Research Center co.ltd. Tianjin300300China

With the increasing integration of traditional elec-tric vehicles(EVs),the ensuing congestion and overloading issues have threatened the reliability of power grid *** has been advocated as a promising energy carrier to achieve low-carbon transportation and energy(trans-energy)systems,which can support the popularization of fuel-cell hybrid EVs(FCHEVs)while enhancing the flexibility of power *** this paper,we propose an optimal scheduling framework for trans-energy systems that evaluates the merits of the hydrogen supply chain from water electrolysis,compressed storage and transportation to FCHEV utilization.A detailed FCHEV model is established,and mileage is modeled as a function of the stored electricity and hydrogen mass.A stochastic programming-based scheduling model is formulated,which minimizes the total cost of unit commitment and the hydrogen supply *** Dijkstra algorithm is adopted to search the shortest path for hydrogen *** studies demonstrate that FCHEVs can reduce the operational costs of tran-energy systems and facilitate the accommodation of renewable energy when compared to traditional *** Terms-Fuel-cell hybrid electric vehicle,hydrogen,mileage model,shortest path search,trans-energy systems.

关键词： Fuel-cell hybrid electric vehicle hydrogen,mileage model shortest path search trans-energy systems.

Experimental Investigations on NO_(x) Emission and combustion Dynamics in an Axial Fuel Staging combustor

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Journal of Thermal Science 2022年第1期31卷 198-206页

作者： LI Yuze JIA Yuliang JIN Ming ZHU Xutong GE Bing MAO Ronghai REN Lilei CHEN Mingmin JIAO Guangyun Key Laboratory of power Machinery and engineering of Ministry of Education Shanghai Jiaotong UniversityShanghai 200240China china United Gas Turbine Technology co.ltd. Beijing 100016China Shanghai electric Gas Turbine co.ltd. Shanghai 200240China

Axial Fuel Staging(AFS)technology is an advanced low-emission combustion method in modem gas turbine,which divides the combustor into two axially arranged combustion *** revealing the characteristics of axial staged combustion,an industrial-grade combustor was designed and *** distribution of temperature and velocity field in the combustor was presented with numerical *** an Atmospheric combustor Test Rig for axial staged combustion was *** flow resistance characteristics of the combustor were measured at *** the effects of the equivalent ratio and the preheating temperature on the pollutant emission and combustion instability were *** results show that the total pressure recovery coefficient in cold state is always above 98%;starting the secondary combustion at low load can reduce NO emissions by 50%,and can suppress the combustion oscillation amplitude of the *** the design point with φ=0.62 and preheating temperature=400°C,NO emission and co emission are 15.68 and 4.22 mg/m^(3)(@15%O_(2)).

关键词： Axial Fuel Staging(AFS)technology the equivalent ratio preheating temperature NO emissions combustion dynamics

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Numerical study of scattering Legendre moments and effect of anisotropic scattering on S_N shielding calculation

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Nuclear Science and Techniques 2019年第11期30卷 95-107页

作者： cong Liu Xiao-Li Hu Bin Zhang You Gong Liang Zhang Yi-Xue Chen School of Nuclear Science and engineering North China Electric Power UniversityBeijing 102206China china Nuclear power engineering co.ltd. Beijing 100840China china Institute of Atomic Energy Beijing 102413China

In neutron and photon transport problems,anisotropic scattering is of great importance for the particle flux,especially when the angular flux has a strong forward peak in shielding *** conventional Legendre expansion is widely used in discrete ordinates transport codes because of algebraic simplifications with spherical harmonics for the scattering ***,negative cross sections caused by the finitely truncated expansion may give rise to a negative source and flux.A simple method is adopted,based on integrating functions of scattering moments,to evaluate anisotropy and convergence of expanded functions.A series of problems were designed with angular fluxes of different anisotropy,and numerical simulations were performed using the ARES transport code to study different treatments and algorithms for *** show that the diagonal transport approximation is more stable and obtains a similar accuracy with the extended approximation.A conservative fixup for the negative source could ensure particle balance and improve computational accuracy significantly for photon *** effect of anisotropic scattering is problem-dependent,and no distinct differences among various methods are observed for volume source problems with a continuous energy *** beam source problems,flux results are sensitive to negative scattering functions,and strictly nonnegative cross sections need to be implemented.

关键词： Particle transport Shielding calculation Discrete ordinates method Anisotropic scattering Transport approximation Negative source fix-up

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Broadband impedance spectrum detection of buffer layer defects in 110 kV crosslinked polyethylene cable with corrugated aluminium sheath

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High Voltage 2023年第5期8卷 967-976页

作者： Yanpeng Hao Peng Zhao Baojun Hui Yanting Cheng Wenbo Zhu Mingli Fu Xiaodong Li School of electric power engineering South China University of TechnologyGuangzhouChina china Southern power Grid electric power Research Institute co.ltd GuangzhouChina

The buffer layer defects of high‐voltage crosslinked polyethylene(XLPE)cable occur frequently,which makes the detection method become the focus to be ***,the broadband impedance detection technology for the buffer layer defects of high‐voltage XLPE cables with corrugated aluminium sheath is *** are nine cable samples,including new and defective *** of the defective cables are artificial,and the other is retired *** influence of wiring mode,the circumferential relative position of electrodes,cable length,artificial white powder,artificial damp,and retired defective cables on the impedance spectrum is *** is found that the wiring mode of the insulation shield/aluminium sheath at the end of the cable can effectively detect the buffer layer *** the broadband impedance amplitude spectrum of the buffer layer in defective cable,measuring at various circumferential relative positions,is obviously *** there are white powders,air gaps,or ablation in the buffer layer,the broadband impedance spectrum(BIS)will increase by several *** the buffer layer is damped,the BIS will *** research here provides theoretical support and technical methods for the buffer layer defects of XLPE cable with corrugated aluminium sheath.

关键词： impedance spectrum layer

Dispatch Model for Integrated Heat and power Systems considering Internal composition of CHP Plants

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CSEE Journal of power and Energy Systems 2021年第2期7卷 396-407页

作者： Tuo Jiang Yong Min Guiping Zhou Lei Chen Qun Chen Fei Xu Department of electrical engineering Tsinghua UniversityBeijing 100084China State Grid Liaoning electric power Supply co.ltd. Shenyang 110000China Department of engineering Mechanics Tsinghua UniversityBeijing 100084China

An integrated heat and power system(IHPS)is a promising approach for alleviating wind curtailment *** an IHPS,the combined heat and power(CHP)plant is the key component,which supplies both heat and electric loads,and couples the thermal system and power ***,existing research commonly ignores or simplifies the internal composition of CHP plants,which could lead to some unavoidable *** paper focuses on the internal composition of CHP plants,and models the physical processes in different components and flexible resources in the CHP ***,a joint dispatch problem of an IHPS with the above CHP plant models is formulated,and an iterative algorithm is developed to handle the nonlinearity in this *** studies are performed based on a real CHP plant in Northern china,and the results indicate that the synergistic effect of different energy resources in the CHP plant is realized by the joint dispatch model,which promotes wind power accommodation and reduces fossil fuel consumption.

关键词： combined heat and power(CHP)plant CHP unit economic dispatch Integrated heat and power system wind power integration