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A Hybrid Integrated and Low-Cost Multi-Chip Broadband Doherty Power Amplifier Module for 5G Massive MIMO Application
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作者 Fei Huang Guansheng Lv +2 位作者 Huibo Wu Wenhua Chen Zhenghe Feng 《Engineering》 SCIE EI CAS CSCD 2024年第7期223-232,共10页
In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabric... In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabricated using the gallium arsenide(GaAs)integrated passive device(IPD)process,is proposed for 5G massive multiple-input multiple-output(MIMO)application.An inverted DPA structure with a low-Q output network is proposed to achieve better bandwidth performance,and a single-driver architecture is adopted for a chip with high gain and small area.The proposed DPA has a bandwidth of 4.4-5.0 GHz that can achieve a saturation of more than 45.0 dBm.The gain compression from 37 dBm to saturation power is less than 4 dB,and the average power-added efficiency(PAE)is 36.3%with an 8.5 dB peak-to-average power ratio(PAPR)in 4.5-5.0 GHz.The measured adjacent channel power ratio(ACPR)is better than50 dBc after digital predistortion(DPD),exhibiting satisfactory linearity. 展开更多
关键词 5G Doherty power amplifier Multi-input multi-output Multi-chip modules hybrid integrated
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Multifunctional light-field modulation based on hybrid nonlinear metasurfaces
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作者 钱树航 王凯 +3 位作者 杨加兴 关超 龙华 陆培祥 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第10期73-89,共17页
The generation characteristics of nonlinear optical signals and their multi-dimensional modulation at micro-nano scale have become a prominent research area in nanophotonics,and also the key to developing various nove... The generation characteristics of nonlinear optical signals and their multi-dimensional modulation at micro-nano scale have become a prominent research area in nanophotonics,and also the key to developing various novel nonlinear photonics devices.In recent years,the demand for higher nonlinear conversion efficiency and device integration has led to the rapid progress of hybrid nonlinear metasurfaces composed of nanostructures and nonlinear materials.As a joint platform of stable wavefront modulation,nonlinear metasurface and efficient frequency conversion,hybrid nonlinear metasurfaces offer a splendid opportunity for developing the next-generation of multipurpose flat-optics devices.This article provides a comprehensive review of recent advances in hybrid nonlinear metasurfaces for light-field modulation.The advantages of hybrid systems are discussed from the perspectives of multifunctional light-field modulation,valleytronic modulation,and quantum technologies.Finally,the remaining challenges of hybrid metasurfaces are summarized and future developments are also prospected. 展开更多
关键词 light-field modulation hybrid metasurfaces nonlinear optics two-dimensional materials
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A New DC Side Capacitance Voltages Balancing Method for Three-level Inverters Based on Hybrid Space Vector Modulation 被引量:6
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作者 Fan Bishuang Tan Guanzheng +1 位作者 Fan Shaosheng Deng zelin 《中国电机工程学报》 EI CSCD 北大核心 2012年第27期I0017-I0017,共1页
关键词 直流侧电容电压 空间矢量调制 三电平逆变器 平衡方法 混合 基础 平衡算法 功率驱动器
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An Improved Submodule Unified Pulse Modulation Scheme for a Hybrid Modular Multilevel Converter 被引量:2
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作者 Sizhao Lu Kai Li +2 位作者 Xiaoting Deng Siqi Li Zhengming Zhao 《CES Transactions on Electrical Machines and Systems》 2017年第3期322-333,共12页
This paper presents an improved submodule unified pulse width modulation(SUPWM)scheme for a hybrid modular multilevel converter(MMC)composed of half-bridge submodules(HBSMs)and full-bridge submodules(FBSMs).The propos... This paper presents an improved submodule unified pulse width modulation(SUPWM)scheme for a hybrid modular multilevel converter(MMC)composed of half-bridge submodules(HBSMs)and full-bridge submodules(FBSMs).The proposed SUPWM scheme can achieve an output voltage of(2N+1)(where N is the number of submodules in each arm)levels,which is the same as that of the carrier-phase-shifted PWM(CPSPWM)scheme.Meanwhile,the proposed SUPWM scheme can alleviate the uneven loss distributions between the left leg and right leg in FBSMs of the hybrid MMC.Moreover,the capacitor voltages of the sub-modules can be well balanced without complicated closed-loop voltage balancing controllers.The validity of the proposed SUPWM scheme is verified by both the simulated and experimental results. 展开更多
关键词 hybrid MMC loss distribution pulse width modulation
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Research of Hybrid Modulation Radar Signal
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作者 Kai-Feng Guo Yun Lin +1 位作者 Meng Wang Xiao-Chun Xu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第3期35-39,共5页
Based on the advantage of phase coded signal and stepped frequency signal,a new hybrid modulation signal is introduced in this paper. It combines phase code modulation during the pulse with stepped frequency modulatio... Based on the advantage of phase coded signal and stepped frequency signal,a new hybrid modulation signal is introduced in this paper. It combines phase code modulation during the pulse with stepped frequency modulation between the pulses, which is named as phase-coded stepped-frequency ( PCSF ) signal. By analyzing its waveform and ambiguity function,the comparison between Stepped-Frequency ( SF) signal and PCSF signal is given,which shows that the PCSF signal is better than SF signal. Finally,the signal processing method with two stage compressed processing is presented. The simulation results show that this new hybrid modulation radar signal can get a higher stepped frequency than ordinary SF signal,realize the same equivalent bandwidth with less pulse number,and solve the conflict among the stepped frequency,the number of pulse, and transmit average power. Under the premises of a certain range resolution,this new hybrid modulation radar signal not only raises the data rate of radar system,but also reduces Doppler sensitivity with a good prospect, and the effect of one-dimensional range profile is much better than that of traditional SF signal. Therefore,this new hybrid modulation radar signal can be widely used in application. 展开更多
关键词 phase coded stepped frequency hybrid modulation signal ambiguity function signal processing
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Performance analysis and code recognition for dual N-ary orthogonal hybrid modulation systems
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作者 乔晓强 Zhao Hangsheng Cai Yueming 《High Technology Letters》 EI CAS 2008年第2期113-117,共5页
A dual N-ary orthogonal hybrid modulation system is introduced in this paper, which can increase the data rate greatly compared with conventional N-ary orthogonal spread spectrum system, so it can be used for high rat... A dual N-ary orthogonal hybrid modulation system is introduced in this paper, which can increase the data rate greatly compared with conventional N-ary orthogonal spread spectrum system, so it can be used for high rate data communication. Then, three code recognition algorithms are presented for dual N-ary orthogonal hybrid modulation system and the analytic bit error rate (BER) performance of the system in additive white Gaussian noise (AWGN) and fiat Rayleigh fading channel is derived. Finally, the computer simulation of the system with three code recognition algorithms is performed, which shows that the simplified maximum a posteriori (MAP) algorithm is the best for the system with a compromise between the performance and the complexity. 展开更多
关键词 code recognition N-ary orthogonal spread spectrum hybrid modulation MAP (maxi-mum a posteriori) algorithm
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Research on Modulation Strategies Based on Multilevel Inverter Universal Hybrid Topology
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作者 ZhouJinghua SuYanmin ShenChuanwen ZhangLin 《Electricity》 2005年第2期53-59,共7页
Based on multi-module-cascaded inverter topology, this study presented a universal multilevel inverter hybrid topology and unified the researches on multilevel inverter topology. According to the freedom of this unive... Based on multi-module-cascaded inverter topology, this study presented a universal multilevel inverter hybrid topology and unified the researches on multilevel inverter topology. According to the freedom of this universal topology, several new hybrid topologies were constructed. Also, based on conventional modulation strategies- multi-carrier SPWM (Sinusoidal Pulse Width Modulation), hybrid modulation strategies were introduced corresponding to hybrid topologies, and a multilevel SVPWM (Space Vector Pulse Width Modulation) technique based on phase-shifted theory was naturally produced. Simulation and experiment results prove that hybrid topologies and corresponding modulation strategies are valid, which lay a foundation for practical application of hybrid multilevel inverter topologies. 展开更多
关键词 MULTILEVEL hybrid topologies MULTI-CARRIER modulation strategies
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Organic electro-optic polymer materials and organic-based hybrid electro-optic modulators 被引量:1
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作者 Yan Wang Tongtong Liu +3 位作者 Jiangyi Liu Chuanbo Li Zhuo Chen Shuhui Bo 《Journal of Semiconductors》 EI CAS CSCD 2022年第10期28-38,共11页
High performance electro-optic modulator,as the key device of integrated ultra-wideband optical systems,have be-come the focus of research.Meanwhile,the organic-based hybrid electro-optic modulators,which make full us... High performance electro-optic modulator,as the key device of integrated ultra-wideband optical systems,have be-come the focus of research.Meanwhile,the organic-based hybrid electro-optic modulators,which make full use of the advant-ages of organic electro-optic(OEO)materials(e.g.high electro-optic coefficient,fast response speed,high bandwidth,easy pro-cessing/integration and low cost)have attracted considerable attention.In this paper,we introduce a series of high-perform-ance OEO materials that exhibit good properties in electro-optic activity and thermal stability.In addition,the recent progress of organic-based hybrid electro-optic devices is reviewed,including photonic crystal-organic hybrid(PCOH),silicon-organic hy-brid(SOH)and plasmonic-organic hybrid(POH)modulators.A high-performance integrated optical platform based on OEO ma-terials is a promising solution for growing high speeds and low power consumption in compact sizes. 展开更多
关键词 organic electro-optic materials modulATOR organic-based hybrid modulator heterogeneous integration
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A Hybrid Si IGBT and SiC MOSFET Module Development 被引量:2
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作者 Puqi Ning Lei Li +1 位作者 Xuhui Wen Han Cao 《CES Transactions on Electrical Machines and Systems》 2017年第4期360-366,共7页
A compact wirebond packaged phase-leg SiC/Si hybrid module was designed,developed,and tested.Details of the layout and gate drive designs are described.The IC chip for gate drive is carefully selected and compared.Dua... A compact wirebond packaged phase-leg SiC/Si hybrid module was designed,developed,and tested.Details of the layout and gate drive designs are described.The IC chip for gate drive is carefully selected and compared.Dual pulse test confirmed that,the switching loss of hybrid module is close to pure SiC MOSFET module,and it is much less than pure Si IGBT device.The cost of hybrid module is closer to Si IGBT. 展开更多
关键词 Gate drive design hybrid module SiC device.
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Optical transmitter module with hybrid integration of DFB laser diode and proton-exchanged LiNbO_(3)modulator chip
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作者 Xuyang Wang He Jia +2 位作者 Junhui Li Yumei Guo Yu Liu 《Journal of Semiconductors》 EI CAS CSCD 2022年第6期34-39,共6页
In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fib... In this work,a hybrid integrated optical transmitter module was designed and fabricated.A proton-exchanged Mach–Zehnder lithium niobate(LiNbO_(3))modulator chip was chosen to enhance the output extinction ratio.A fiber was used to adjust the rotation of the polarization direction caused by the optical isolator.The whole optical path structure,including the laser chip,lens,fiber,and modulator chip,was simulated to achieve high optical output efficiency.After a series of process improvements,a module with an output extinction ratio of 34 dB and a bandwidth of 20.5 GHz(from 2 GHz)was obtained.The optical output efficiency of the whole module reached approximately 21%.The link performance of the module was also measured. 展开更多
关键词 optical transmitter module hybrid integration DFB laser chip LiNbO3 modulator chip
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Contribution to Harmonic Depollution Control by the Use of Adaptive Hybrid Filter Type TLC: Case of Control by Modulated Hysteresis
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作者 Luc Vivien Assiene Mouodo Jean Gaston Tamba +4 位作者 Olivier Sosso Mayi Antoine Hanna Nohra Lawren Bibaya Maurice Fadel Hadi Kanaan 《Energy and Power Engineering》 2020年第10期578-602,共25页
In this article, we propose a topology of a TLC-HAPF power filter as a harmonic compensator for an optimization of the pollution control of electrical networks. This filter consists of an active part and a passive par... In this article, we propose a topology of a TLC-HAPF power filter as a harmonic compensator for an optimization of the pollution control of electrical networks. This filter consists of an active part and a passive part in order to reduce or limit switching losses during current injection into networks thanks to its TLC module. This topology also provides solutions dynamic performance issues, resonance and lack of compensation capacity for imbalance cases. It also offers a greater range of compensation than conventional active models which do not offer as well as an intermediate circuit voltage in the order of 105 V to 109 V relatively lower than others models (600 v). A modulated hysteresis control of this topology is therefore also developed in this article and allows to obtain a network analysis on the three phases at three levels: source side, load side, and finally at the connection of the filter to the network, allowing to specify for these different positions the value of the current spectrum and its THD at this well-defined moment. 展开更多
关键词 hybrid Adaptive Active Filter modulated Hysteresis THD Harmonic Pollution Control
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Docking process on hybrid self-reconfigurable modular robots
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作者 帅立国 Su Huizhe +1 位作者 Zheng Liyuan Fei Yanqiong 《High Technology Letters》 EI CAS 2017年第1期71-76,共6页
A novel hybrid self-reconfigurable modular robot is designed to finish the morphing action from line shape to hexagon shape. The robot is composed of many basic modules,each of which consists of a master module and a ... A novel hybrid self-reconfigurable modular robot is designed to finish the morphing action from line shape to hexagon shape. The robot is composed of many basic modules,each of which consists of a master module and a slave module in the shape of triangular prism. There are four connection ports on each basic module. For the master module there are two holes on each connection port,and for the slave one there are two pegs on each connection. The docking process between two neighboring basic modules is analyzed with a peg-in-hole mechanical structure. A small motion's method is presented and the contact forces are derived. According to the force/moment,the pose of a motion module should be adjusted to make two neighboring modules align and finish the docking process.Finally,a simulation of 3 basic modules is shown to finish the morphing and docking process effectively. The system can finish the morphing task from the line shape to the hexagon shape. 展开更多
关键词 self-reconfigurable robot MORPHING hybrid modulE
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Hybrid Simulation of Duty Cycle Influences on Pulse Modulated RF SiH_4/Ar Discharge
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作者 王喜凤 宋远红 +2 位作者 赵书霞 戴忠玲 王友年 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第4期394-399,共6页
A one-dimensional fluid/Monte-Carlo(MC)hybrid model is developed to describe capacitively coupled SiH_4/Ar discharge,in which the lower electrode is applied by a RF source and pulse modulated by a square-wave,to inv... A one-dimensional fluid/Monte-Carlo(MC)hybrid model is developed to describe capacitively coupled SiH_4/Ar discharge,in which the lower electrode is applied by a RF source and pulse modulated by a square-wave,to investigate the modulation effects of the pulse duty cycle on the discharge mechanism.An electron Monte Carlo simulation is used to calculate the electron energy distribution as a function of position and time phase.Rate coefficients in chemical reactions can then be obtained and transferred to the fluid model for the calculation of electron temperature and densities of different species,such as electrons,ions,and radicals.The simulation results show that,the electron energy distribution f(ε)is modulated evidently within a pulse cycle,with its tail extending to higher energies during the power-on period,while shrinking back promptly in the afterglow period.Thus,the rate coefficients could be controlled during the discharge,resulting in modulation of the species composition on the substrate compared with continuous excitation.Meanwhile,more negative ions,like Si H_3^-and Si H_2^-,may escape to the electrodes owing to the collapse of ambipolar electric fields,which is beneficial to films deposition.Pulse modulation is thus expected to provide additional methods to customize the plasma densities and components. 展开更多
关键词 hybrid model EEDF pulse modulation SiH_4/Ar mixture
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Performance and Stability of Supercapacitor Modules based on Porous Carbon Electrodes in Hybrid Powertrain
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作者 龚旋 谢长君 +3 位作者 ZOU Yaohui QUAN Shuhai PIOTR Bujlo SHEN Di 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2014年第6期1141-1146,共6页
Hybrid power sources have attracted much attention in the electric vehicle area. Particularly, electric-electric hybrid powertrain system consisting of supercapacitor modules and lithium-ion batteries has been widely ... Hybrid power sources have attracted much attention in the electric vehicle area. Particularly, electric-electric hybrid powertrain system consisting of supercapacitor modules and lithium-ion batteries has been widely applied because of the high power density of supercapacitors. In this study, we design a hybrid powertrain system containing two porous carbon electrode-based supercapacitor modules in parallel and one lithium ion battery pack. With the construction of the testing station, the performance and stability of the used supercapacitor modules are investigated in correlation with the structure of the supercapacitor and the nature of the electrode materials applied. It has been shown that the responding time for voltage vibration from 20 V to 48.5 V during charging or discharging process decreases from about 490 s to 94 s with the increase in applied current from 20 A to 100 A. The capacitance of the capacitor modules is nearly independent on the applied current. With the designed setup, the energy efficiency can reach as high as 0.99. The results described here provide a guidance for material selection of supercapacitors and optimized controlling strategy for hybrid power system applied in electric vehicles. 展开更多
关键词 supercapacitor modules electric-electric hybrid powertrain charging-discharging cycle stability power density
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一种高性能低成本的中压异质器件混合型模块化多电平变换器及其控制策略
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作者 周志 涂春鸣 +4 位作者 侯玉超 郭祺 任鹏 刘红文 杨金东 《电网技术》 EI CSCD 北大核心 2024年第9期3686-3694,I0046,I0047-I0049,共13页
针对少子模块数的中压模块化多电平变换器(modular multilevel converter,MMC)装置损耗、成本等指标难以综合提升的问题,该文提出一种基于Si基绝缘栅双极型晶体管(insulated gate bipolar transistor,IGBT)和SiC基金属氧化物半导体场效... 针对少子模块数的中压模块化多电平变换器(modular multilevel converter,MMC)装置损耗、成本等指标难以综合提升的问题,该文提出一种基于Si基绝缘栅双极型晶体管(insulated gate bipolar transistor,IGBT)和SiC基金属氧化物半导体场效应晶体管(metal oxide semiconductor field effect transistor,MOSFET)混合的模块化多电平变换器,简称异质器件混合型模块化多电平变换器(heterogeneous device hybrid MMC,HDHMMC)。HDHMMC由全Si IGBT的低频模块和Si IGBT与SiC MOSFET混合的高频模块组成。针对此拓扑提出一种特定的高低频混合调制策略,充分发挥Si IGBT通态损耗低、SiC MOSFET开关损耗低的优势。此外,详细分析了高低频模块的能量波动机理,并针对高低频模块直流侧电容电压不稳定问题提出一种特定的稳压策略。仿真和实验结果验证了HDHMMC拓扑及其调制、稳压策略的可行性。最后,将HDHMMC与现有MMC拓扑进行损耗与成本对比,证明所提拓扑可以更好地平衡成本、效率、功率密度等性能指标。 展开更多
关键词 模块化多电平变换器 Si IGBT SiC MOSFET 混合调制 稳压策略
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一种增加辅助子模块的MMC改进混合调制控制策略
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作者 杨光源 周诗嘉 +3 位作者 彭光强 武霁阳 辛清明 许树楷 《电源学报》 CSCD 北大核心 2024年第1期74-82,共9页
传统的最近电平逼近调制NLM(nearest level modulation)具有控制简单,开关频率低的显著优势,但在输出电平数较少时,采用NLM调制的模块化多电平换流器MMC(modular multilevel converter)输出波形谐波畸变率较大。在传统三相六桥臂MMC拓... 传统的最近电平逼近调制NLM(nearest level modulation)具有控制简单,开关频率低的显著优势,但在输出电平数较少时,采用NLM调制的模块化多电平换流器MMC(modular multilevel converter)输出波形谐波畸变率较大。在传统三相六桥臂MMC拓扑的各桥臂中增加1个全桥结构的辅助子模块,控制该辅助子模块的电容电压为半桥子模块的一半。针对该MMC拓扑,提出了一种改进的混合调制策略,该混合调制策略可以实现半桥和辅助子模块的平衡控制。在降低MMC交流侧输出电流的谐波畸变率同时,还可以降低全桥子模块的开关频率和系统损耗。在Matlab/Simulink中搭建了详细的仿真模型,仿真结果验证了所提MMC拓扑和改进混合调制策略的有效性。 展开更多
关键词 模块化多电平变流器 混合调制 平衡控制 降频控制
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混合储能聚合商参与能量-调频市场控制策略
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作者 范展滔 张鸿轩 +2 位作者 楼楠 刘士齐 金朝意 《电网与清洁能源》 CSCD 北大核心 2024年第5期130-138,共9页
提出了一种混合储能聚合商(hybrid energy storage aggregator,HESA)参与能量-调频市场的控制策略。首先,对于独立系统运营商(ISO)发出的调频指令信号进行VMDWVD时频域分析,重构固有模态分量(IMF)生成高频信号与低频信号,分别作为HESA... 提出了一种混合储能聚合商(hybrid energy storage aggregator,HESA)参与能量-调频市场的控制策略。首先,对于独立系统运营商(ISO)发出的调频指令信号进行VMDWVD时频域分析,重构固有模态分量(IMF)生成高频信号与低频信号,分别作为HESA中功率型储能和能量型储能的输入信号。其次,构建了计及多市场价格不确定性的HESA投标与运行策略min-max-min模型,基于列和约束生成算法(C&CG)和强对偶理论对主子问题进行迭代交替求解。最后,基于实际PJM市场的价格、调频信号等数据进行了仿真,验证了HESA主体投标运营策略的有效性。 展开更多
关键词 储能系统 混合储能聚合商 锂电池 超级电容 能量-调频市场控制策略
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AOS中基于最优帧长的链路自适应联合优化方法
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作者 刘庆利 郭梦田 商佳乐 《计算机应用与软件》 北大核心 2024年第4期106-111,共6页
针对AOS中数据传输误码率高的问题,导致系统吞吐量低的问题,提出基于最优帧长的链路自适应联合优化方法。该方法以系统吞吐量最大化为目标,联合可变帧长,自适应编码调制和混合自动重传请求技术进行优化,根据信道状态信息分配下一帧传输... 针对AOS中数据传输误码率高的问题,导致系统吞吐量低的问题,提出基于最优帧长的链路自适应联合优化方法。该方法以系统吞吐量最大化为目标,联合可变帧长,自适应编码调制和混合自动重传请求技术进行优化,根据信道状态信息分配下一帧传输最佳的帧长和编码调制方式,并对出错数据进行纠错和重传,最终提升系统吞吐量。仿真验证表明,与AMC-HARQ和AMC-ARQ方法相比,该方法在保证系统误帧率的同时,提高了系统的吞吐量。 展开更多
关键词 AOS空间通信 最优帧长 自适应编码调制 混合自动重传
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考虑异质器件混用与输出电平倍增的混合型MMC及其调控方法 被引量:1
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作者 任鹏 涂春鸣 +3 位作者 侯玉超 郭祺 刘海军 王鑫 《电力系统自动化》 EI CSCD 北大核心 2024年第5期128-136,共9页
首先,为提高模块化多电平换流器(MMC)输出波形质量、降低装置运行损耗,提出一种基于Si和SiC器件组合应用的混合型模块化多电平变换器(HMMC)拓扑结构。该拓扑每个桥臂包含N个Si绝缘栅双极晶体管(IGBT)器件的半桥子模块,每相交流侧串联一... 首先,为提高模块化多电平换流器(MMC)输出波形质量、降低装置运行损耗,提出一种基于Si和SiC器件组合应用的混合型模块化多电平变换器(HMMC)拓扑结构。该拓扑每个桥臂包含N个Si绝缘栅双极晶体管(IGBT)器件的半桥子模块,每相交流侧串联一个直流侧电压为半桥子模块一半的SiC金属-氧化物半导体场效应晶体管(MOSFET)全桥子模块,整体经济性较好。其次,提出一种面向输出电平数倍增的HMMC高、低频混合调制策略,并充分发挥SiC MOSFET开关损耗低的优势,在减小HMMC输出谐波的同时降低整体运行损耗。此外,分析混合调制策略下HMMC异质子模块直流侧能量的波动规律,提出一种高、低频模块直流侧电压稳定控制策略。最后,仿真和实验验证了所提HMMC拓扑结构和调制策略的可行性,并将所提HMMC、基于单一器件MMC和现有HMMC在损耗和成本方面进行综合对比,证明了该方案在降低损耗和减小成本方面优势显著。 展开更多
关键词 模块化多电平换流器 Si绝缘栅双极晶体管 SiC金属-氧化物半导体场效应晶体管 混合调制 电压平衡控制 效率优化
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基于SCSO-SVM算法的光伏组件故障识别 被引量:1
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作者 郁纪 肖文波 +1 位作者 李欣蕊 吴华明 《科学技术与工程》 北大核心 2024年第3期1066-1074,共9页
光伏阵列通常被安装在恶劣的室外环境中,因此在运行过程中易发生故障。为了准确识别光伏阵列的故障类型,提出沙猫群优化支持向量机(sand cat swarm optimization support vector machine,SCSO-SVM)用于光伏组件故障识别,且对比支持向量... 光伏阵列通常被安装在恶劣的室外环境中,因此在运行过程中易发生故障。为了准确识别光伏阵列的故障类型,提出沙猫群优化支持向量机(sand cat swarm optimization support vector machine,SCSO-SVM)用于光伏组件故障识别,且对比支持向量机(support vector machine,SVM)、粒子群优化支持向量机(particle swarm optimized support vector machine,PSO-SVM)、遗传优化支持向量机(genetic optimized support vector machine,GA-SVM)、麻雀优化支持向量机(sparrow optimized support vector machine,SSA-SVM)、灰狼优化支持向量机(gray wolf optimized support vector machine,GWO-SVM)和鲸鱼优化支持向量机(whale optimized support vector machine,WOA-SVM)算法。首先,六种SVM混合算法都克服了SVM诊断结果易受参数初始值影响的缺点,识别精度相较传统SVM算法都有所提升,但是识别时间都增加。其次,7种算法中SCSO-SVM识别效果最好,克服了SVM易受参数初始值的影响,相较SVM识别精度提高了约9.4594%;是因为更能有效找到SVM惩罚因子和核函数参数。然后,对于同一种算法而言,算法的识别精度是随输入特征减少而降低的,是因为输入特征越少,越不能有效表征光伏组件在不同故障类型下的输出属性。但算法的识别时间却不是随输入特征减少而减短。所以选取合适的输入特征才能兼顾算法的故障识别准确率和效率。最后,发现七种算法的识别效果依赖于数据集的影响。原因可能是各个算法参数选择过多导致泛化性有差异,且依赖参数初始值选择。 展开更多
关键词 光伏组件 故障识别 支持向量机 混合算法 沙猫群算法
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