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关键词： 分布式变频器   汽车焊装车间   输送领域  

摘要： 在汽车焊装车间，分布式变频器的应用比较普遍，相比集中控制方式，该设备的应用优势比较突出。该设备可以节约安装空间、提升防护等级，可直接应用于车间现场作业，达到控制使用成本的效果。本文对分布式变频器进行概述，分析其在汽车领域的应用优势，并总结了其在汽车焊装车间输送领域的具体应用情况，最后展望了该设备在汽车领域的应用发展趋势。

关键词： 分布式驱动电动汽车   纵-垂向运动协同控制   轮胎非线性   线性参数时变模型   快速控制原型  

摘要： 以分布式电驱动底盘为载体的电动汽车赋予车辆更为灵活和模块化的控制模式。然而，在复杂城市交通场景下，车辆频繁的加减速行为对整车的纵-垂向运动控制提出极大的挑战，为此，旨在利用转矩矢量控制与主动悬架系统的集成提升分布式驱动电动汽车的纵、垂向综合运动性能。首先，面向直线行驶工况，构建半车动力学模型，考虑到轮胎的非线性特性，通过拟合轮胎力，实时求解等效的轮胎侧偏刚度，在此基础上，引入线性参数时变模型解决车速与侧偏刚度带来的系统不确定性问题，从而降低算法优化过程的计算负担；其次，采用模型预测控制将车辆安全、节能及舒适性作为控制目标，其中轮胎滑移率及电机效率、执行器能耗及车辆垂向运动等指标作为目标函数进行优化，控制器求解过程推导了满足系统多性能要求的硬约束条件；选取ECE(联合国欧洲经济委员会汽车法规)作为测试工况，通过快速控制原型试验对所设计的算法进行了验证，结果表明，该控制器能够在保证车辆稳定的基础上，综合提升整车的节能性和舒适性，在连续加速行为下，轮胎最大滑移率较线性二次规划算法可降低约24%，电机效率可以保持在88%以上，同时垂向运动性能也可得到极大改善。

关键词： 2-step   4-quadrant switch   4-step   current commutation   efficiency   matrix converter   ON state voltage drop   Si IGBT   SiC MOSFET   turn ON/OFF times   2-step   4-quadrant switch   4-step   current commutation   efficiency   matrix converter   ON state voltage drop   Si IGBT   SiC MOSFET   turn ON/OFF times  

摘要： Silicon Carbide (SiC) MOSFETs are promising replacements for Silicon (Si) IGBTs in various power electronic topologies. While extensive research exists on SiC MOSFET based 2-quadrant switches, studies on 4-quadrant switch topologies remain limited. A 4-quadrant switch is typically formed by combining multiple 2-quadrant switches such as MOSFETs, IGBTs, or diodes. Designing such topologies presents challenges, including commutation methods (2-step and 4-step), finite switching speed constraints, variable ON state voltage drops, and quadrant-dependent transition (turn ON/OFF) times. This research systematically investigates these challenges through analysis, simulation, and experimental validation in a controlled FPGA based test environment. The study focuses on selecting an optimal commutation method, analysing the impact of 2-step and 4-step switching on transition times and ON state voltage drops, and evaluating the maximum switching frequency and efficiency of converters utilizing SiC MOSFET based 4-quadrant switches. The findings demonstrate the advantages of these converters in terms of reduced transition times, higher switching frequencies, and improved efficiency, establishing SiC MOSFET based 4-quadrant switches as a viable alternative to Si IGBT based designs.

关键词： 换流回路   死区时间   压接式IGBT   开关损耗均衡   三电平有源中点钳位  

摘要： 针对压接式IGBT组成的功率单元换流暂态时间优化及损耗平衡问题，依据产生损耗位置将三电平有源中点钳位单元的32种换流回路分为5种．为提高输出谐波特性，研究换流暂态过程进而优化切换暂态时间．利用4.5 V/3 A压接式IGBT制作了低杂感功率单元，设计双脉冲实验研究暂态电压电流变化规律．将开关暂态过程分成6种，并迭代优化死区时间．实验结果表明：死区时间优化后可以实现安全换流，换流过程的电压电流变化规律与理论分析一致．

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.