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关键词： Silicon carbide  

摘要： A 13 kV class n-channel 4H-SiC trench gate insulated gate bipolar transistor (IGBT) structure is designed based on Silvaco TCAD device simulator tool. The influence of metal/SiC and SiC MOS interface trap states on the static and dynamic characteristics of SiC IGBT devices are systematically studied. It is found that the electrical properties of SiC IGBTs are insensitive to the donor or acceptor traps at the interface of metal/SiC and the donor traps at the SiC/SiO2 interface. However, the acceptor traps at the SiC/SiO2 interface affect the electrical properties of SiC IGBTs greatly. When the acceptor trap density at the SiC/SiO2 interface (D-ita) is up to the level of 10(12) cm(-2)center dot eV(-1), the turn-on voltage drop (V-CEON) is increased gradually with the augmentation of D-ita. The breakdown voltage (V-BR) of the device is increased slightly. Further study of the device's turn-off characteristics shows that the turn-off loss (E-OFF) is decreased with the increase in Dita but a large tail current is formed. The mechanism may be that when the electrons are injected from the N+ source region into the N- drift region, the SiC/SiO2 interfacial acceptor traps at the side wall of trench gate capture a large number of electrons. As a result, the minority carrier concentration is decreased, and the conductance modulation effect on the N- drift region is weakened. (c) 2023 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://***/licenses/by/4.0/).

关键词： 农业电动机   变频器   控制应用  

摘要： 近年来,我国农业生产机械化程度越来越高,电动机的使用也越来越多,农业机械对电动机的性能要求也越来越高,既要适应农业生产的需要,又要符合机械设备的使用寿命和性能要求,因此,提高电动机的多档转速性能和精度是今后的主要发展方向。本文从农业生产机械对电动机转速的要求出发,介绍了变频器控制技术在多档转速中的应用情况,包括变频器与传统机械设备的控制对比、变频器在农业生产中应用存在问题、多档转速对电动机性能要求、多档转速对变频器技术要求以及多档转速对电动机节能降耗、降低噪声等几个方面进行了论述。

关键词： 超环面电机   最大转矩电流比控制   矢量控制   极值原理  

摘要： 为充分利用永磁超环面电机的电磁转矩,研究了超环面电机最大转矩电流比MTPA(maximum torque per ampere)矢量控制系统。首先,分析了超环面电机蜗杆内定子变截面的结构特点和行星轮磁齿的运动规律,推导了永磁超环面电机驱动系统的时变数学模型;然后基于极值原理和公式法,得到永磁超环面电机输出转矩与交直轴电流的函数关系;结合闭环反馈得到行星轮转子的位置信息,搭建了该电机的MTPA控制系统,并对MPTA控制策略下的超环面电机响应性能进行了仿真分析。仿真结果表明,MTPA控制策略能够提高超环面电机电磁转矩的利用率,有效降低该电机的功率损耗,同时该控制系统具有良好的抗扰性能以及对参数变化的鲁棒性。

关键词： 变频器   IGBT组件   驱动电路   参数设置  

摘要： 阐述AB PF700型变频器的故障原因,IGBT组件的驱动电路、封装及内部问题,探讨应对的措施,包括改善散热环境、变频器内部的控制、对老化器件进行预防性更换、参数设置降低变频器发热量。

关键词： 变频器调速技术   电气自动化控制   电机驱动  

摘要： 随着电气自动化技术的不断发展,由于变频器调速的特殊原理,对电气工程具有突出作用,未来变频器调速技术还有巨大的发展前景。基于此,本文首先介绍了变频器调速技术的基本原理及其特点,然后重点分析了变频器调速技术在电气自动化控制系统中的典型应用场景,如电机驱动、泵浦系统、输送装置等。并对其未来发展趋势进行了探讨。

关键词： 有机硅凝胶   封装材料   功率模块   IGBT模块  

摘要： 为了评估国产有机硅凝胶在绝缘栅双极晶体管(IGBT)功率模块封装中的应用情况,选取了3种国产有机硅凝胶进行综合性能对比,包括固化前外观、密度、黏度、混合比例和凝胶时间,固化后绝缘性能、渗油性、阻尼性、粘附性和200℃下耐高温性能等。分析了3种有机硅凝胶样品的差异,并利用其分别封装IGBT功率模块,对所封装的模块进行温度循环测试。结果表明:有机硅凝胶的起始黏度和混合比例对封装工艺和封装设备有影响,固化后锥入度、绝缘性能、渗油性、阻尼性、粘附性等性能对有机硅凝胶型号的选用有指导作用,耐高温性能和耐温度循环能力是评估样品能否用于IGBT功率模块封装重要的指标。

关键词： 晶闸管   二极管   IGBT   相控整流  

摘要： 电力电子整流装置在市场上有着广泛的运用。主要的整流方式包括有二极管整流、晶闸管整流和IGBT整流。二极管整流和晶闸管整流具有控制简单的特点,但是不具备四象限运行的能力。IGBT整流具有四象限能力,但系统天生是难以稳定的,所以需要快速响应的闭环控制来达到系统稳定的目的,因此其对控制系统的要求偏高。因此,本文提出了一种新的控制方式,具有四象限能力且控制简单。

关键词： Insulated gate bipolar transistors   Finite element analysis   Transient analysis   Surface morphology   Resistance heating   Molybdenum   Logic gates   Heat dissipation   press-pack insulated gate bipolar transistor (PP-IGBT)   short-circuit capability   short-circuit failure  

摘要： Press-pack insulated gate bipolar transistor (PP-IGBT) device has been widely used in VSC-HVdc converters. Research on the optimization method of short-circuit capability is crucial to improve the short-circuit robustness and reliability of PP-IGBT. Aiming at the problem of device failure due to transient overstress induced by press-pack packaging, this article proposes a short-circuit capability optimization method of PP-IGBT that improving the active edge heat dissipation by using silver conductive adhesive (SCA). First, the short-circuit capability is evaluated by experimental test, and the failure conditions and positions are obtained. Second, based on the finite element method simulation, the electrical-thermal-mechanical stress of PP-IGBT under short-circuit transients is analyzed and the optimization method by using SCA is proposed. Third, the short-circuit capability of PP-IGBT with SCA coating is tested and verified. Lastly, the potential of the SCA coating under different short-circuit voltage levels is discussed. The results indicate that the transient thermal shock at the active corner of the chip that is not in direct contact with the emitter molybdenum plate causes device failure and improving the active edge heat dissipation by SCA could be an effective approach to improve the short-circuit capability of PP-IGBT.

ISBN: (纸本)9787111725800