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关键词： 无差拍控制   鲁棒稳定性   测量噪声抑制   混合预测   硬件在环测试平台  

摘要： 在工程化实现过程中，常规无差拍电流跟踪控制实际上演变为差一拍控制，导致有源电力滤波器谐波补偿性能的下降。本文在分析系统延时对数字控制影响的基础上，综合采用自适应前向线性预测和重复预测算法提前2个采样时刻预测谐波补偿参考电流，以系统动态是否发生为依据，设定两种预测算法切换的判别条件。为了提前一拍预测逆变器输出电流，同时有效抑制测量噪声，逆变器电流预测环节同时使用待补偿谐波参考电流和输出电流历史数据作为输入。无差拍控制高度依赖主电路数学模型，对模型准确性高度敏感，抗噪声干扰能力较差，为此本文分析了主电路输出滤波电感和电阻参数发生偏移情况下所提预测型无差拍控制的稳定性，进一步分析了电流和电压测量噪声在系统中的传递情况。最后，本文对三种预测型无差拍控制进行了仿真和实验对比研究，验证了本文所提混合预测型无差拍控制算法的有效性。

摘要：

Wide and ultrawide bandgap semiconductors demonstrate exceptional performance due to their large energy bandgap, which offers distinctive advantages such as enhanced efficiency, drift velocity, increased voltage blocking, and high-frequency switching. These characteristics make such semiconductors essential for advancing electronic technology. Among such materials, diamond is particularly distinguished for its wide bandgap, superior thermal conductivity, and high electron mobility. These properties enable diamond to perform exceptionally well in challenging environments where traditional materials may fail. Additionally, its ability to operate at elevated temperatures and voltages renders diamond-based devices suitable for a range of applications, including high-power electronics and high-frequency RF systems.

The hydrogen-terminated Metal-Oxide Field Effect Transistor (HD-MOSFET) is a highly promising and widely studied diamond device. In this device, hydrogen termination is used to induce a two-dimensional hole gas (2DHG) as high as 10¹⁴ cm^-2, resulting in high drain current.

Our study investigates the Hydrogen-Terminated Diamond Metal-Oxide Field-Effect Transistor (HD-MOSFET) using TCAD Sentaurus to gain insights into the thermal performance and operational limits of diamond-based semiconductor devices. In this study, we examine the trapping effect and temperature-dependent behavior of the HD-MOSFET. Furthermore, our analysis compares the effects of temperature and interface traps on the threshold voltage (V_th), channel mobility (µ_ch), and on-state resistance (R_ON) within a temperature range of 300 K to 500 K.

摘要：

As metal-oxide-semiconductor field-effect transistors (MOSFETs) devices approach their dimensional scaling limits, 3D structures such as gate-all-around FETs (GAAFETs) have been introduced to improve the electrical characteristics of transistors by increasing the effective channel width. In modern logic devices with a GAA structure, in-situ doped epitaxial silicon is grown on recessed source/drain (S/D) regions using selective epitaxial growth (SEG) process. However, the SEG process poses a competitive disadvantage in terms of complexity and cost. To simplify the integration process, we propose a method for forming S/D without relying on SEG. In this study, we investigate the formation of S/D using nanosecond laser annealing process in devices with multilayer channels. Three pairs of Si/Si_0.7Ge_0.3 multilayer films were deposited on Si (100) substrates using ultra-high vacuum chemical vapor deposition (UHVCVD). After deposition, boron and phosphorus dopants were implanted into the structure. Samples were then subjected to nanosecond laser annealing under various conditions using a krypton fluoride (KrF) pulse laser. Finally, we obtained recrystallized and doped films that function as S/D. Transmission electron microscopy (TEM) confirmed the microstructure of recrystallized films as function of increasing laser power density. Additionally, the dopant distribution was analyzed using secondary ion mass spectrometry (SIMS). High resolution X-ray diffraction (HR-XRD) was employed to examine the strain behavior in the films. Results indicate that the nanosecond laser annealing process is a viable method for forming S/D in devices with Si/SiGe multilayer channels.

Acknowledgements

This work was supported by the Joint Program for Samsung Electronics at Yonsei University and the Technology Innovation Program (20010598) funded by the Ministry of Trade, Industry & Energy (MOTIE).

关键词： 太阳能   太阳电池   环境影响   风速分布   温度分布   预测模型  

摘要： 为解决不断发展的大规模光伏发电接入电网后带来的调度问题，基于流体力学与热力学理论，提出一种用于预测光伏组件温度分布及其功率的模型。与传统的基于大数据与神经网络预测组件表面平均温度的方法相比，该模型一方面不依赖于历史测量数据，缺少相关数据也不妨碍其高精度的预测；另一方面可预测光伏组件表面的温度分布，并据此预测功率，具有更高的预测准确度。

关键词： 三电平   Buck变换器   解耦控制   前置滤波器  

摘要： 为提升三电平Buck变换器的稳定性能，提出一种基于前置滤波器的精确反馈解耦控制策略。建立三电平Buck变换器的数学模型，并基于逆系统理论对模型进行可逆性分析，将原模型线性化解耦为2个伪线性子系统；对2个子系统分别设计比例—积分控制器和最优控制器，以提高系统的性能和抑制外部扰动对系统的影响；进而设计前置滤波器，以消除闭环零点的不利影响。与现有控制方法相比，仿真和实验结果表明，所提控制策略具有更快的响应速度、更好的稳定性和更强的鲁棒性。

关键词： 构网型变流器   虚拟同步发电机   振荡抑制机理   q轴虚拟功率构造   有功功率振荡抑制  

摘要： 构网型变流器的输出有功功率可能会发生低频振荡，而传统抑制功率振荡的控制策略会引入额外的稳态有功功率偏差，或者需要依赖附加检测环节获取电网电压角频率。此外，当电网阻抗发生变化时，采用不合适的控制参数亦存在功率振荡的风险。针对上述问题，本文提出了一种基于q轴虚拟功率构造的有功功率振荡抑制控制策略。首先，通过电路分析得出结论，并网点电压的q轴分量包含变流器输出角频率与电网电压角频率之差的信息。基于该结论，利用q轴电压构造出一个虚拟功率，并引入滤波器滤除高频分量对系统的影响。同时，指出构造的功率可以等效为准谐振控制器的输出，输入则为q轴电压。基于复数力矩系数法，分析了提出策略抑制功率振荡的机理。进一步，通过建立小信号模型，说明了所提策略不会改变变流器的有功-频率稳态下垂特性，并给出了关键控制参数的设计方法。最后，根据PSCAD/EMTDC以及硬件在环半实物实验平台的仿真和实验结果，验证了所提控制策略的优势。

关键词： 有源消弧   单相接地故障   消弧线圈   站内电容器   多功能变流器  

摘要： 凭借兼具无功功率支撑(reactive power support， RPS)与接地故障调控(grounding fault control， GFC)能力，复合装置得到了广泛关注。但是，既有复合装置存在容量过高、需要额外附加供电装置的问题。针对上述问题，基于充分利用既有站内资源的思想，本文提出了一种基于站内资源的新型无功功率支撑与接地故障调控复合装置(RPS and GFC composite device，RGCD)。首先，本文介绍了RGCD的拓扑结构与运行原理，RGCD由站内电容器、站内消弧线圈和多功能变流器(multi-functional converter，MC)构成，当电网正常运行时，站内电容器补偿负荷所需的大部分无功功率，剩余部分由MC进行补偿；当发生单相接地故障时，站内电容器进行无功补偿，站内消弧线圈和MC进行接地故障调控，在不同运行模式下均实现了MC容量降低。其次，分析了接地故障调控期间的能量流动机理，并提出了基于直流侧电压稳定的P-Q两相消弧方法，实现了免供电装置下RGCD的稳定运行。最后，通过仿真验证了所提拓扑及运行原理的有效性与可行性。

关键词： 核反应堆   堆芯功率   分数阶PID控制器   人工神经网络  

摘要： 堆芯功率是核反应堆运行的重要参数之一.对堆芯功率的控制通常用比例-积分-微分（PID）控制器.分数阶PID控制器是当前堆芯功率控制研究的前沿.使用分数阶微积分能更好地建模堆芯功率的时变性，更真实地描述堆芯功率状态的变化.但是，多数分数阶控制器无法根据环境或需求的变化及时调整其参数、实现快速动态响应.本文基于人工神经网络（ANN）极强的自学习能力提出了一种复合控制器.该控制器将人工神经网络与分数阶控制器结合起来，不仅可以实时参数调优，还保留了分数阶PID控制器的优点，同时实现堆芯功率的稳定控制和动态响应.