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关键词： Power MOSFET  

摘要： Regular removal of thin film depositions from vapor deposition chambers is a critical step in semiconductor manufacturing processes, directly impacting the efficiency and quality of production. Traditional manual disassembly cleaning methods have several drawbacks, including the necessity for shutdown operations, cooling treatment and breaking the vacuum, all of which consume considerable time and disrupt the production process. In contrast, plasma cleaning causes less damage to the chamber interior and has therefore become the preferred cleaning method. However, maintaining plasma stability requires a drive power supply with consistent current and frequency to prevent plasma extinction. In this article, the electrical characteristics of the drive power supply for the plasma generation device (PGD) are discussed, considering its dynamic and nonlinear load characteristics of plasma. Through analysis of the equivalent circuit, the condition of current gain equal to 1 is analyzed, thereby achieving the constant-current output. A Power MOSFET-based test platform was established and experimental results validate the effectiveness of the analysis. © 1988-2012 IEEE.

关键词： 大功率掘进机   内喷雾   结构设计   外喷雾  

摘要： 大功率掘进机在截割减速机外形较大的前提下，内喷雾结构设计上可颠覆以往在悬臂筒外径引入外来水的设计思路，将水路变为由截割电机尾端接入，整个中轴线布置内喷雾水路结构，端部轴承架起保证同轴；与悬臂筒外径引入结构相比，所选密封件型号小，各零件加工精度易控，各过渡环节采用的静密封可靠性更高。中轴线布置的内喷雾系统相对独立，后续维护方便。

关键词： 数据分析   模式识别   故障诊断   光伏电站   箱式变压器  

摘要： 阐述基于人工智能算法的光伏电站箱式变压器典型故障诊断方法。通过数据分析和模式识别技术，有效提升了设备的可靠性和运行效率。该方法在故障的早期发现与精确定位方面具有显著优势。

关键词： 涡扇发动机   功率提取   高空   性能   稳定性  

摘要： 针对高空工作的涡扇发动机功率提取能力不足的问题，提出从低压转子提取功率的方法，基于正在研制的某双轴混排中等涵道比涡扇发动机，建立发动机性能模型，计算从低压转子提取功率对发动机的影响。结果表明，相比从高压转子提取功率，从低压转子提取功率能显著提高发动机的稳定裕度。对于在高空环境工作的涡扇发动机，从低压转子提取功率能在保障发动机安全工作的前提下提高功率提取能力。

关键词： 风电场数据特征   功率预测   PT二次回路   灰狼寻优算法   门控循环单元  

摘要： 由于风力具有不确定性，导致风电波动性较强。为了对风电功率进行准确的预测，建立基于数据特征的功率预测系统。根据风电场数据特征对数值天气预报(NWP)风速数据进行修正，对异常风电数据进行滤波和补齐处理，并对风电机组进行实时监测，实现风电场经济性运行。风电场电能采集模块完成对风电场龙风线、主变线路高压侧、变压器等信息的采集。采用电压互感器(PT)二次回路压降的方法提高测量精度。利用拉丁超立方抽样策略(LHS)对灰狼寻优算法进行改进，保证种群初始参数抽样过程的稳定性，建立基于门控循环单元网络的功率预测系统，实现对风电功率的预测。实验结果显示，风电功率预测系统的训练时间仅为845 s,平均预测误差低于5%,预测精度最大。

关键词： 换流站   功率数据   自动采集   数据监控  

摘要： 阐述基于换流站消息邮件系统的功率数据自动采集传输设备的设计，可实现自动化监控和数据分析，图形化展示功率调节次数和计划功率，自动生成汇报信息。该系统通过智能终端设计，拓展了消息邮件系统功能，提升了数据监控和分析的效率。

关键词： Lanthanum oxide   monte carlo simulation   double-gate MOSFET   quantum effects   potential distribution   particle transport   drift velocity   conduction band energy   packing density  

摘要： Introduction This work proposes a Double-Gate (DG) MOSFET with a Single Material made of Silicon On-Insulator (SOI). The Lanthanum Oxide material with a high k-dielectric constant has been used as an interface between two gates and the channel. The Monte Carlo analysis has been used to determine the Conduction Band Energy (Ec) profiles and electron sheet carrier densities (ns) for a Silicon channel thickness (tsi) of 10 nm at 0.5 V gate drain-source voltages. The transverse electric fields are weak at the midchannel of DG SOI MOSFETs, where quantum effects are encountered. The Monte Carlo simulation has been confirmed to be effective for high-energy transport. A particle description reproduces the granularity property of the transport for nanoscale *** This work utilizes a Monte Carlo (MC) Simulation for the proposed Double Gate Single Material Silicon On Insulator MOSFET with (La2O3=2 nm) as dielectric oxide on upper and lower gate material. The electrical properties of the DG SOI MOSFETs with Lanthanum Oxide were analyzed using Monte Carlo simulation, including the conduction band energy, electric field, potential distribution, particle movement, and average *** The peak electric field (E) simulation results and an average drift velocity (upsilon avg) of 6x105 V/cm and 1.6x107 cm/s were obtained, respectively. The conduction band energy for the operating region of the source has been observed to be 4% to the drain side, which obtained a value of -0.04 eV at the terminal *** This proposed patent design, such as double-gate SOI-based devices, is the best suggestion for significant scalability challenges. Emerging technologies reach the typical DG SOI MOSFET's threshold performance when their geometrical dimensions are in the nanometer region. This device based on nanomaterial compounds has been more submissive than conventional devices. The nanomaterials usage in the design is more suitable for downscaling and reducing packaging

关键词： 有源电力滤波器   机场   行李   处理系统   谐波抑制  

摘要： 为提高机场行李处理系统运行的稳定性，避免系统谐波对机场电网造成干扰，利用有源电力滤波器，设计了机场行李处理系统谐波抑制方法。首先，对机场行李处理系统谐波作出评估，准确了解机场行李处理系统电力供应系统中谐波的分布情况、含量以及对系统的影响。其次，进行有源电力滤波器选型与安装，为谐波抑制奠定良好的基础。最后，设计谐波抑制方案，通过自适应调整与PWM调制，实现谐波有效抑制的目标。实验结果表明，提出的方法应用后，系统谐波畸变率显著降低，最高不超过0.5%,减小了谐波对机场电网和设备的不良影响，提高了系统的稳定性和可靠性。

关键词： MOSFET   Current measurement   Silicon carbide   Inductance   Inductors   Semiconductor device measurement   Parasitic capacitance   Voltage measurement   Power measurement   Mathematical models   Air-core inductor   correction method   dynamic measurement   parasitic parameters   RC snubber  

摘要： The dynamic turn-off measurement of SiC MOSFETs is highly sensitive to parasitic parameters in the measurement circuit due to their extremely high di/dt and dv/dt. In particular, the parasitic capacitance in the load inductor and the parasitic inductance in the power loop significantly affect the turn-off measurement results. Therefore, this study first reveals the mechanisms by which these two parasitic parameters affect the turn-off measurement results. Then, this study proposes a design method for the load inductor and a measurement method for turn-off currents to achieve accurate turn-off measurements. Specifically, the equivalent model and analytical expression for the equivalent parasitic capacitance in the load inductor are established. Based on this expression, a winding suggestion for the inductor coil is introduced to minimize parasitic capacitance, reducing it below 5 pF. The proposed current measurement method, utilizing an RC snubber, effectively addresses the reduction in the turn-off current falling rate caused by parasitic inductance in the power loop. Experimental verification demonstrates that the turn-off current measured using the RC snubber-based method closely matches the reference waveform.

关键词： 电子束焊机   高功率密度电子束   束流密度测量   微孔法拉第杯  

摘要： 电子束焊机中的电子束具有功率密度高（106～108 W/cm2）、焦斑尺寸小（几百微米）的特点。其束流密度分布是一项重要的束流品质参数，对焊接工艺研究具有重要意义。然而，传统的电子束密度测量方法（比如荧光成像法）在如此高的功率密度下无法使用。研究了一种基于水冷微孔法拉第杯与高频束流扫描相结合的测量方法。在电子束焊机偏转线圈上加高频（1～10 kHz）信号，使电子束在较大尺寸范围内扫描，从而降低电子束沉积在法拉第杯表面的功率密度，避免法拉第杯表面被烧毁。可用于真空腔体中的水冷微孔法拉第杯是经过特别设计的，通过水冷带走电子束损失在法拉第杯的表面上的热量。法拉第杯表面有一个数十微米尺寸的微孔。当电子束周期性地经过微孔时，少量电子束通过微孔会进入法拉第杯，形成电信号并经过集成在法拉第杯中的放大器放大后被采集。电子束功率密度分布可由采集到的时域内的电流信号进行重建得到。实验证明，该方法可以准确测量电子束焊机中高功率密度电子束的密度分布，同时具有约23μm的成像精度。