Results 11 to 20 of about 7,888 (166)
ABSTRACT Integrating light emission and electromagnetic wave (EMW) absorption into a single material opens up possibilities for multienvironmental applications. Herein, we propose a novel “molecular engineering‐pyrolysis conversion” strategy to construct a bifunctional system with tunable photoluminescence and efficient EMW absorption performance.
Renjie Wang +7 more
wiley +1 more source
ABSTRACT The inherent brittleness of hardmetals stems from the rigid covalent bond in the ceramic matrix and the sharp ceramic/metal interface, which restricts the nucleation and motion of dislocations. In this study, a novel strategy is proposed to activate significant dislocation behaviors in the WC matrix by employing a non‐equiatomic CoNiFeCr ...
Cheng Qian +9 more
wiley +1 more source
针对电网电压出现不平衡会导致储能变流器(power conversion system,PCS)输出的有功功率波动、无功功率波动和三相电流峰值越限问题,文中提出了一种考虑电流峰值限制的储能变流器协调控制策略。首先分析了传统控制策略在电网电压不平衡下的局限性;其次利用瞬时功率理论与加权思想,在αβ两相静止坐标系上实现抑制有功功率波动与抑制无功功率波动的协调控制;然后在上述基础上,加入一种电流峰值限制方法,能在PCS进行协调控制的同时保障输出的三相电流峰值不越限 ...
谭丽平 +8 more
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ABSTRACT The utilization of carbonaceous anodes in electrochemical systems, particularly potassium‐ion batteries (PIBs), remains hindered by sluggish kinetics and modest capacities, which are caused by the intrinsic ion storage mechanisms and constrained interlayer spacings.
HaiSong Chen +7 more
wiley +1 more source
ABSTRACT Nickel‐based superalloys (Ni‐based superalloys) have attracted extensive attention in laser additive manufacturing (LAM) due to their capability to directly fabricate complex and high‐performance structural components. However, the rapid melting and solidification inherent to LAM result in intense thermal cycling, which induces high residual ...
Tianxiang Lin +9 more
wiley +1 more source
研究了基于深度强化学习算法的自主式水下航行器(AUV)深度控制问题。区别于传统的控制算法,深度强化学习方法让航行器自主学习控制律,避免人工建立精确模型和设计控制律。采用深度确定性策略梯度方法设计了actor与critic两种神经网络。actor神经网络给出控制策略,critic神经网络用于评估该策略,AUV的深度控制可以通过训练这两个神经网络实现。在OpenAI Gym平台上仿真验证了算法的有效性。
王日中, 李慧平, 崔迪, 徐德民
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针对光伏逆变器并网电流谐波较大的问题,首先对三电平逆变器的主电路结构进行了分析,得出了网侧输出电流的数学模型,并分析了该模型下逆变器谐波产生的机理。在分析了传统的PI+重复控制的基础上,针对传统PI与重复控制相互耦合容易导致等效重复控制对象不稳定的问题,提出了一种双PI+重复控制(double proportional integral + repetitive control,DPI+RC)的控制策略。采用PI补偿,在保证了传统PI+重复控制系统跟踪的快速性和准确性前提下,确保了系统的稳定性。最后 ...
刘重洋 +4 more
doaj +1 more source
Study and Design of V2G system based on Grid-connected PV Power Generation [PDF]
随着分布式可再生能源渗透率的不断提高,光伏等可再生能源接入电网的方式更加多样。同时近年来电动汽车飞速发展,解决充电问题已成为当务之急。在减少大规模充电对电网产生影响的同时,将电动汽车作为储能单元参与电网的调峰调频有利于电网的安全经济运行。本文研究基于光伏发电的V2G系统,旨在增加新能源消纳并促进电动汽车的清洁化和低碳化。系统的最大创新点在于实现了光伏发电并网、电动汽车充电与V2G服务的分时复用。 针对家庭单相并网选取了双向两级式的电路拓扑,不仅结构简单而且易于控制。对双向全桥电路和Buck ...
孙纯鹏
core
ABSTRACT Thermally driven hydrogenation of CO2 to light olefins (C2=–C4=) using metal oxide‐zeolite tandem catalysts is an effective strategy for achieving carbon neutrality. However, progress in this area is constrained by zeolite pore transport limitations, acid‐site inactivation, and surface carbon poisoning.
Haifeng Tian +10 more
wiley +1 more source
为了解决光伏发电在电网电压跌落过程中,逆变器两侧功率不平衡出现过电流和过电压的问题,设计了一种定功率跟踪控制的光伏并网低电压穿越策略。通过定功率跟踪控制对光伏阵列输出功率进行调节,根据电压跌落深度,合理给定功率参考值,控制光伏阵列的功率输出,实现交、直流侧功率的快速平衡,限制直流母线电压的增长。通过逆变器无功补偿控制,不仅能限制并网电流在安全范围内,还能够根据跌落深度提供无功支撑,有效地利用了逆变器自身的无功调节能力。结果表明,该策略能够抑制过电压和过电流,使系统具备一定的低电压穿越能力。最后 ...
董广凯 +4 more
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