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Journal of Advanced Ceramics 2021年第6期10卷 1360-1370页

作者： Ying XIONG Hongyuan XIE Zhenggang RAO Laijun LIU zhengfeng wang Chunchun LI College of Information Science and Engineering Guilin University of TechnologyGuilin 541004China Guangxi Key Laboratory of Optical and Electronic Materials and Devices College of Material Science and EngineeringGuilin University of TechnologyGuilin 541004China School of Materials Science and Engineering Nanchang UniversityNanchang 330031China

AB_(2)O_(4)-type spinels with low relative permittivity(ε_(τ))and high quality factor(Q×f)are crucial to high-speed signal propagation *** this work,Zn^(2+)/Ge^(4+) co-doping to substitute Ga in ZnGa_(2)O_(4) was designed to lower the sintering temperature and adjust the thermal stability of resonance frequency ***_(1+2)Ga_(2-2x)Ge_(x)O_(4)(0.1≤x≤0.5)ceramics were synthesised by the conventional solid state ***^(2+)/Ge^(4+) co-substitution induced minimal variation in the macroscopical spinel structure,which effectively lowered the sintering temperature from 1385 to 1250℃.All compositions crystallized in a normal spinel structure and exhibited dense microstructures and excellent microwave dielectric *** compositional dependent quality factor was related to the microstructural variation,being confirmed by Raman features.A composition with x=0.3 shows the best dielectric properties with ε_(τ) ≈10.09,Q×f≈112,700 THz,and ε_(τ) ≈-75.6 ppm/℃.The negative τf value was further adjusted to be near-zero through the formation of composite ceramics with TiO_(2).

关键词： ceramics spinel composition modulation dielectric properties

Analysis of a reduced-ML algorithm in BLAST

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Science in China(Series F) 2008年第12期51卷 2094-2100页

作者： PAN Wen JIANG ZhanJun DU zhengfeng wang Yan YOU XiaoHu National Mobile Communications Research Laboratory Southeast University Nanjing 210096 China

The performance of ML algorithm is much better than other algorithms in the MIMO wireless communication system. However, it is based on the expense of an increase in the complexity. A reduced maximum likelihood （RML） algorithm is proposed in this paper, which derives from the combination of the ML and ZF algorithms. It is shown that the complexity of RML is far lower than that of ML, while in the same performance condition by both theoretic analyses and simulation.

关键词： MIMO BLAST ML

Application of Submerged Ultrafiltration in Pretreatment of Flue Gas Desulfurization Wastewater

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Energy Engineering 2022年第6期119卷 2277-2296页

作者： Jiageng Zhang zhengfeng wang Jiguang Huang Chao Cheng Heng Zhang Dan Gao School of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China Hebei Construction&Investment Group Xuanhua Thermal Power Co. Ltd.Zhangjiakou075100China

Nowadays,the zero liquid discharge of flue gas desulfurization(FGD)wastewater from coal-fired units has attracted the attention of all countries in the *** pretreatment methods generally have the problems of high operation cost,small treatment capacity,and poor ***,the membrane method can avoid the above *** the current research,it has not been found that someone directly uses submerged ultrafiltration to pretreat FGD ***,this paper innovatively proposed to directly use ceramic ultrafiltration membrane to treat FGD wastewater,which can ensure effluent quality and improve the flexibility of the pretreatment *** this paper,the performance of submerged ultrafiltration membrane for the filtration of FGD wastewater from a power plant was studied to optimize the filtration performance and improve the effluent *** effects of operating parameters such as membrane permeate flux,aeration rate and filtration/backwashing time combination on the membrane performance were *** results showed that when the filtration/backwashing time combination was 15 min/30 s,with the increased in permeate flux from 55 L/(m2·h)to 100 L/(m2·h),the steady transmembrane pressure(TMP)increased from 39 kPa to 70 kPa,and the fouling rate increased significantly from 4.5 kPa/h to 7.3 kPa/h;When the aeration rate increased from 10 m3/(m2·h)to 30 m3/(m2·h),the membrane pollution was much *** aeration rate cannot further alleviate the membrane pollution,but also brought greater energy consumption;Increasing backwashing time can effectively inhibit the formation of gel layer on the surface of the membrane and prolong the initial stage of low-pressure operation;The rejection of suspended solids(SS)and turbidity of the equipment studied in this paper can reach more than 99%under various working conditions,which can satisfy the water quality requirements of the subsequent *** submerged ultrafiltration membrane was suitable

关键词： FGD wastewater pretreatment submerged ultrafiltration permeate flux aeration rate backwashing membrane fouling

A writable lithium metal ink

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Science China Chemistry 2020年第10期63卷 1483-1489页

作者： wangyan Wu Jian Duan Jiayun Wen Yuwei Chen Xuyang Liu Liqiang Huang zhengfeng wang Shengyuan Deng Yunhui Huang Wei Luo Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China

The recent revival of Li metal anodes(LMA)leads to a renewed interest in LMA as the ultimate choice for rechargeable lithium batteries towards high energy ***,multiple challenges stand in the way of using LMA,of which high reactivity,dendrite growth,the difficulty of fabricating Li thin foils,and the flammability of organic liquid electrolytes are ***,a writable Li metal ink(LMI)prepared by introducing biomass-derived carbon particles into molten Li is *** to the significantly decreased surface tension,LMI is able to directly write on copper foils or other substrates that ultrathin Li foils with a remarkably small thickness(<10μm)can be *** versatility of LMI is further demonstrated in addressing the interface issue between LMA and garnet-type solid-state electrolytes,where directly writing LMI on the garnet offers a perfect contact and enables an extremely low interfacial resistance of 6Ωcm^2,in sharp contrast to 939Ωcm^2 between the pure Li and the *** to the successful partnership with non-flammable solid-state electrolytes,ink-based technology may have a chance to bring us very close to the use of solid-state lithium metal batteries(SSLMBs)with high safety and high energy density.

关键词： lithium metal ink surface tension solid-state batteries interface controllable thickness

Daily rolling estimation of carbon emission cost of coal-fired units considering long-cycle interactive operation simulation of carbon-electricity market

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Global Energy Interconnection 2023年第4期6卷 467-484页

作者： Mingjie Ma Lili Hao zhengfeng wang Zi Yang Chen Xu Guangzong wang Xueping Pan Jun Li College of Electrical Engineering and Control Science Nanjing Tech UniversityNanjing 211816P.R.China State Grid Anhui Electric Power Co. Ltd.Hefei 230022P.R.China Tianjin Bohai Electric Power Group Co. Ltd.Tianjin 300171P.R.China College of Energy and Electrical Engineering Hohai UniversityNanjing 210008P.R.China School of Economics Hefei University of TechnologyHefei 230601P.R.China

The high overlap of participants in the carbon emissions trading and electricity markets couples the operations of the two *** carbon emission cost(CEC)of coal-fired units becomes part of the power generation cost through market *** accuracy of CEC calculation affects the clearing capacity of coal-fired units in the electric power *** of carbon–electricity market interaction and CEC calculations is still in its initial *** study analyzes the impact of carbon emissions trading and compliance on the operation of the electric power market and defines the cost transmission mode between the carbon emissions trading and electric power markets.A long-period interactive operation simulation mechanism for the carbon–electricity market is established,and operation and trading models of the carbon emissions trading market and electric power market are established.A daily rolling estimation method for the CEC of coal-fired units is proposed,along with the CEC per unit electric quantity of the coal-fired *** feasibility and effectiveness of the proposed method are verified through an example simulation,and the factors influencing the CEC are analyzed.

关键词： Carbon emission trading Carbon emission cost Carbon price Electric power market Market simulation

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基于WAMS的电网调度运行方式安排设计

电力自动化设备 2010年第6期30卷 115-117页

作者：王正风陈实安徽电力调度通信中心安徽合肥230022

提出利用SCADA/EMS、PMU、稳定控制装置、母线负荷预测、发电计划安排、工作票管理以及保护系统的相关数据,通过电网实时动态监测系统的在线稳定计算功能进行电网静态安全分析和暂态稳定计算,并根据稳定计算结果以及提供的辅助策略实现... 详细信息

提出利用SCADA/EMS、PMU、稳定控制装置、母线负荷预测、发电计划安排、工作票管理以及保护系统的相关数据,通过电网实时动态监测系统的在线稳定计算功能进行电网静态安全分析和暂态稳定计算,并根据稳定计算结果以及提供的辅助策略实现对电网一次运行方式的合理安排,从而提高电网运行的安全稳定性。针对电网运行方式预安排中给出了热稳定限额是考虑了事故后的过负荷能力,若在事故后30 min内缺乏有效手段来保障对用户的供电,将造成事故30 min后对用户的限电,指出应在电网运行方式预安排中考虑事故后对用户的供电能力,以避免由于事故后热稳定原因可能引起的对用户供电不可靠问题,从而增强了对用户供电的可靠性。

关键词：调度运行方式安全稳定供电能力可靠性事故

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基于模式识别的电能量数据辨识和校正

电力系统自动化 2009年第4期33卷 100-103页

作者：汪胜和黄太贵王正风安徽电力调度通信中心安徽省合肥市230022

针对电力市场运营对电能量数据准确性提出的实际要求,结合电能量计量系统的实际特点,在传统电能量数据采集的基础上,提出了一种基于模式识别的电能量数据辨识和校正手段。该方法通过分析电能量计量系统的采集过程,将其划分为若干个特征... 详细信息

针对电力市场运营对电能量数据准确性提出的实际要求,结合电能量计量系统的实际特点,在传统电能量数据采集的基础上,提出了一种基于模式识别的电能量数据辨识和校正手段。该方法通过分析电能量计量系统的采集过程,将其划分为若干个特征模式,对不同的特征模式下采用不同的指标,通过对指标综合分析判别电能量数据可靠性,同时采用SCADA积分数据对不可用数据进行校正,提高了电能量数据辨识水平和数据的可用性。

关键词：电能量模式识别辨识校正

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全时间维度调度计划安全校核的设计与应用

中国电力 2020年第5期53卷 48-55页

作者：吴迪王正风刘航国网安徽省电力有限公司安徽合肥230022

由于电网规模日益扩大以及电力市场的推进,电网运行的安全性和可靠性面临更严峻的挑战,调度计划安全校核工作变得尤为重要。针对大时间尺度下无法精确预测负荷及电网结构从而难以进行准确安全校核的情况,设计并开发了全时间维度调度计... 详细信息

由于电网规模日益扩大以及电力市场的推进,电网运行的安全性和可靠性面临更严峻的挑战,调度计划安全校核工作变得尤为重要。针对大时间尺度下无法精确预测负荷及电网结构从而难以进行准确安全校核的情况,设计并开发了全时间维度调度计划安全校核系统。首先从电力调度运行生产流程对月度、周以及日前安全校核功能进行了论述,接着提出了月度、周以及日前全时间维度安全校核的目标。月度以电量完成和发输变电协调优化为目标,周以机组开机方式优化为目标,日前以发电计划为目标。对于月度安全校核,构建基于断面的发电可行域,优化机组的发电可行区间,从而弥补月度负荷预测的误差;对于周安全校核,优化确定机组开机方式;对于日前安全校核,优化发电机组出力。该方法已在某省级电网成功应用,应用结果表明所提出的方法有效,能够满足电网安全校核和生产实际需求。

关键词：安全校核发电可行域阻塞断面灵敏度

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静态功角稳定和静态电压稳定判据比较分析

电力自动化设备 2008年第2期28卷 61-64页

作者：王正风胡晓飞安徽省电力调度通信中心安徽合肥230022

指出用传统的静态功角稳定的静态稳定储备系数评估系统静态功角稳定性的不足在于其过于乐观,并容易造成认识上的误区;静态功角稳定和电压稳定的极限均是求取系统潮流的极限值,但静态功角稳定的推导是建立在单机无穷大系统基础上,静态电... 详细信息

指出用传统的静态功角稳定的静态稳定储备系数评估系统静态功角稳定性的不足在于其过于乐观,并容易造成认识上的误区;静态功角稳定和电压稳定的极限均是求取系统潮流的极限值,但静态功角稳定的推导是建立在单机无穷大系统基础上,静态电压稳定的推导则是建立在电源电压恒定的基础上。从电能物理传输原理上对静态功角稳定判据和静态电压稳定判据进行了推导,从而纠正了由于2个不同假设条件推导出的静态电压稳定和静态功角稳定判据的不足,得出了统一的结论。指出通常当线路两端相位差在45°以内时失稳是静态电压稳定失稳,而超过45°是静态功角稳定失稳;传输感性无功功率影响系统的静态功角稳定,将造成系统静态功角稳定的下降和传输功率的下降,而传输容性无功功率正好相反。

关键词：静态功角稳定静态电压稳定有功功率无功功率

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旋转备用下双馈风电机组初值算法

电力系统自动化 2013年第11期37卷 7-12,133页

作者：李生虎孙莎莎王正风合肥工业大学电气与自动化工程学院安徽省合肥市230009 安徽省电力公司安徽省合肥市230061

风电机组运行参数计算是风电系统稳态调度和暂态分析的基础。恒kopt模型常用于最大功率点跟踪方式下双馈感应发电机(DFIG)初值计算,但是其所得发电机转速与风力机最优转速相矛盾,且不适用于旋转备用方式。文中针对DFIG旋转备用下的初值... 详细信息

风电机组运行参数计算是风电系统稳态调度和暂态分析的基础。恒kopt模型常用于最大功率点跟踪方式下双馈感应发电机(DFIG)初值计算,但是其所得发电机转速与风力机最优转速相矛盾,且不适用于旋转备用方式。文中针对DFIG旋转备用下的初值问题,提出了转速约束和出力约束2种算法。前者取转速固定,但不要求是最优转速,风力机捕捉机械功率已知,待求转子和变流器电压、风电机组有功出力,需要与电网潮流联立求解;后者取风电机组功率已知,待求转子和变流器电压、转速(或桨距角)及风力机出力,与电网潮流独立求解。2种算法的有效约束和待求变量数不同,但得到的风力机和发电机转速相符,均适用于风速低于或高于额定风速情况下的旋转备用运行。算例结果验证了所提模型的可行性和正确性。

关键词：双馈感应发电机旋转备用初值计算转速约束出力约束