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关键词： 水泥窑   余热发电   电气故障   变频器  

摘要： 为了实现水泥生产的稳定高效运行，快速整改系统中可能出现的电气设备事故隐患，本文从PH锅炉入口阀门开关故障、窑尾喂料转子秤跳停故障、煤磨跳停故障、篦冷机2615风机跳停故障四个方面分析、处理系统中的电气故障，结合故障不断学习、掌握相关的电气知识和注意事项，加强电气设备管理，减少了类似电气事故的发生。

关键词： PLC变频器   焦化厂   风机调速   节能改造   自动化控制  

摘要： 本文针对焦化厂风机系统能耗高、控制精度低的问题，研究了基于PLC变频器的调速改造技术。通过分析传统调速方式的局限性，提出了PLC变频器调速改造方案，详细阐述了系统设计、硬件选型和软件编程等关键技术。实际应用表明，该技术可显著提高风机系统的节能效果和控制精度，为焦化行业的节能减排提供了有效解决方案。

关键词： Cryogenic electronics   gate driver   IGBT   MOSFET   cryogenic propulsion   Cryogenic electronics   gate driver   IGBT   MOSFET   cryogenic propulsion  

摘要： To tackle emissions from the aviation industry and make it sustainable, research has been targeting electrifying aircraft. For this aim, articles have been focusing on how to replace regular jet engines with liquid hydrogen as fuel. This would be beneficial as hydrogen is expected to play a dual role, providing fuel for fuel cells to propel the aircraft electrically and to supply cooling to enable high-power density technologies such as superconducting machines and cryogenic power electronics circuits. However, using higher power density, especially cryogenic power electronics, can be challenging. This article investigates cryogenic power electronics for use on all-electric aircraft across different aspects, where it lays out how to integrate power electronics at cryogenic temperature into the architecture of the all-electric aircraft, how to use them with hydrogen fuel cells, and the voltage levels of the system. It reviews different semiconductor device technologies, circuit topologies, and passive devices to be used in power electronics circuitry, as well as logic circuits that are suitable for use at cryogenic temperatures. In addition, the article discusses the challenges of using semiconductor devices at such low temperatures, including the reliability, overall cooling, and recycling of hydrogen.

关键词： 双三相永磁同步电机   矢量控制   离散型非线性磁链观测器   BP神经网络   高频信号注入  

摘要： 针对中低速情况下双三相永磁同步电机无传感器控制精度低，非线性磁链观测器在静止和低速时稳定性差的问题，提出一种结合BP神经网络的离散型非线性磁链观测器。首先，结合电流方程构建非线性磁链观测器并利用欧拉离散法进行离散化；其次，采用BP神经网络优化非线性磁链的固定增益，实现增益在线调节，同时提出自适应高频信号注入方法，解决了非线性磁链观测器受固定增益值限制观测误差大和低速情况下稳定性差的问题；最后，在MATLAB环境下搭建了仿真模型验证提出的算法，并且仿真结果显示新型观测器的位置误差减小了37.5%以上，收敛速度提升了50%以上，有效地抑制系统抖振，具有更强的鲁棒性。

关键词： 变频器   阿尔斯通   IGBT  

摘要： 随着竞价上网、平价上网时代到来以及北方地区限电的大幅缓解，存量项目的政策优势凸显，但老旧风力发电机组因设计、老化、维护等原因可靠性逐年降低，安全隐患突出，需引起高度重视。通过技术改造对老旧机组安全性、保护性、可靠性、易修性四个方面进行提升，将大大释放老旧机组发电能力，降低故障率，取得良好的经济效益。本文主要针对老旧风机变频器内部功率模块的国产化替代进行分析研究，并取得了良好的成效，为高质量风力发电提供参考。

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： The insulated gate bipolar translators (IGBTs) are most widely used in power electronics converters, and the junction temperature is a significant indicator for evaluating the IGBT reliability. In this article, in order to realize non-invasive monitoring of the main power circuit, the Miller plateau current is adopted as the thermo-sensitive electrical parameter (TSEP), and the proposed method can realize high accuracy for monitoring junction temperature of IGBTs. Firstly, the Miller plateau current is adopted and studied as the gate-side TSEP. The turn-off process of IGBT and the character of Miller plateau current are studied. Subsequently, a sampling circuit and the parameters calculation method based on CT have been designed and analysed. The uncertainty and integrability of sampling circuit have been discussed. Finally, the double-pulse test and inverter experimental platforms have been developed to validate the theoretical analysis. The experimental results have confirmed the accuracy of the theoretical analysis, the proposed method can achieve high accuracy and sensitivity for monitoring junction temperature of IGBTs from the gate-drive side. In addition, the sampling circuit is simple and easy to be integrated on the gate-drive circuit. © 2013 IEEE.

关键词： 微分博弈   Nash均衡   变分不等式   时滞微分方程   最优控制  

摘要： 文章研究具有延时效应的非线性微分广义Nash均衡算法.为刻画具有延时效应的动态广义Nash均衡问题、参与者效益函数和约束集被状态变量影响,文章利用时滞微分方程描述状态变量变化过程,将静态广义Nash均衡发展为时滞微分广义Nash均衡.现有微分Nash均衡主要以Bellman动态规划技术和Pontryagin极值原理为基础进行计算,该方法因为时滞产生的奇异点容易导致计算失败.为解决此问题,文章融合欧拉方法和变分方法,构建算法得到非线性时滞微分广义Nash均衡系统有效解.基于时滞微分变分方法基础,文章对非线性时滞微分广义Nash均衡系统算法进行收敛性分析以验证算法的有效性,最后利用数值算例对算法进行模拟仿真.

关键词： 北斗卫星   时间同步信号   运营商地面网络   基站   通信网络  

摘要： 本文深入研究了北斗卫星时间同步信号在运营商地面网络中的传输问题。随着北斗卫星系统的不断完善和覆盖，其在时间同步方面的优势逐渐显现，特别是在安全、稳定以及地面遮挡区域（如隧道、地铁）内的时间信号质量方面。然而，由于现有运营商网络中早期部署的4G基站GPS接收器不支持北斗卫星信号（BDS）接收，而大规模更换基站卫星信号接收器则需大量资金投入，因此需要探索一种通过地面承载网络进行北斗卫星时间同步信号传输的经济合理、稳定可靠的解决方案。

关键词： 高超声速飞行器   上升段   最优控制   三角正则化法   延拓法  

摘要： 针对高超声速飞行器(hypersonic vehicles, HSV)上升段燃耗最优控制问题，基于间接法，引入了三角正则化方法.该方法弥补了间接法的不足：对复杂最优控制问题的一阶最优必要条件的推导烦琐，奇异最优控制求解难，且控制不平滑.针对间接法转化的两点边值问题中，协态变量初值猜测难以给出而使求解易发散的问题，引入并改进了延拓法.其用简化问题的解作为延拓初值，通过求解一系列两点边值问题，逐步逼近到原复杂问题.计算表明，上述方法能够可靠求解复杂模型下HSV上升段燃耗最优控制问题.

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： In this study, the robustness of insulated gate bipolar transistors (IGBTs) under extreme high-gate voltage stress (both positive and negative) is comprehensively investigated. The results indicate that all IGBTs maintain essential electrical characteristics, demonstrating considerable robustness to extreme gate voltage stress. However, varying degrees of degradation are observed depending on the polarity of the applied stress. Specifically, under high-positive gate voltage stress, the threshold voltage remains nearly stable, whereas under high-negative gate voltage stress, a significant increase in the threshold voltage is noted. Based on these findings, the degradation mechanism is proposed and experimentally validated. For negative gate voltage stress, degradation primarily results from electron injection from the gate, with elevated temperatures accelerating this process. In contrast, under positive gate voltage stress, the hole injection efficiency is much lower than that of electrons, and part of the gate voltage is absorbed by the depletion region. Additionally, G-V measurement, C-V measurement, and simulation are conducted to support the proposed mechanism. This work contributes to a deeper understanding of IGBT degradation mechanisms under high-gate voltage stress, offering insights relevant for their application in high-stress operational environments. © 1963-2012 IEEE.