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关键词： 复合材料平板结构   增强型鲸鱼优化算法   最优控制   振动控制  

摘要： 针对复合材料平板结构在结构振动控制中控制器参数难以优化的问题，设计了一种基于增强型鲸鱼优化算法(EWOA)优化的最优二次型(LQR)算法(EWOA-LQR)。WOA由于其结构简单、参数少、优化能力强等优点，已被应用于许多不同的工程优化问题。通过池化机制的引入和迁徙、优先选择和丰富包围猎物这3种有效搜索策略的运用，来增强标准WOA的性能，将EWOA应用于LQR控制器参数的优化。为了验证优化后的EWOA对复合材料平板结构振动的有效控制，采用EWOA-LQR控制器，运用压电纤维片(MFC)在不同工况下对复合材料平板结构振动完成了控制仿真。结果表明：EWOA-LQR算法在不同工况下有着良好的控制效果，具有较强的鲁棒性，为复合材料平板结构振动控制提供了一种新的思路和方法。

关键词： Permanent magnets  

摘要： Aiming at the problems of poor accuracy, slow convergence rate and high jitter of traditional super-twisting sliding mode observer, a permanent magnet synchronous motor(PMSM) speed observation technique based on the improved super-twisting algorithm was proposed. Firstly, a segmented exponential function was used to replace the switching function to eliminate the phase delay problem due to the low-pass filter, and the adaptive sliding mode gain was designed to achieve stable tracking at different speeds. Then, in order to solve the problem that the traditional quadrature phase-locked loop failed when the motor steering was changed, an improved quadrature phase-locked loop was proposed, so that its output was independent of the rotation direction, so as to realized the correct tracking of the forward and reverse rotation. Finally, due to the wrong convergence point of the proposed improved quadrature phase locked loop, there was a 180° phase difference between the estimated position and the actual position, an adjustment function was designed to solve this problem. The simulation results show that compared with the traditional sliding mode observer, the proposed improvement method has faster response and better dynamic performance. © 2025 Beijing Kexue Jishu yu Gongcheng Zazhishe. All rights reserved.

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： Bond wire lift-off is a major aging failure mode in Insulated Gate Bipolar Transistor (IGBT) modules, critically impacting their safe and reliable operation. This paper presents power cycling aging experiments on IGBT modules. With increasing power cycles, the IGBT module exhibits a significant rise in both on-state voltage drop and junction temperature, as shown by the results. Disassembly of failed modules revealed that bond wires at the IGBT chip edge exhibited lifting and peeling of the pins. A current-thermal-structural multi-physics coupling model was developed to investigate the mechanism of bond wire lift-off during power cycling. Simulations showed concentrated current density and stress at the pins edges where bond wires, chip surface, and silicone gel meet. Uneven chip surface temperature distribution, due to solder layer aging, stressed the end pins at the module edge, causing initial micro-cracks. Compared to a healthy state, the current and stress fields at the micro-crack increased by 421.4% and 1024.1%, respectively, accelerating crack propagation and leading to complete end pin lift-off. This lift-off further degraded the bonding of other healthy bond wires, ultimately causing module failure. These results provide a reference for IGBT module aging failure analysis and reliability design. © 2011-2012 IEEE.

关键词： 变频器   典型故障   EXB841  

摘要： 变频器是舰炮随动系统的重要组成部分，确保变频器正常工作对提升舰炮作战效能具有重要意义。为此，分析了该型变频器组成与原理，并针对使能故障、IGBT模块故障与电流检测故障，通过搭载测试环境，定位至具体故障器件，给出了维修思路和方法。相关经验可供解决变频器故障参考。

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： Multiple parallel insulated-gate bipolar transistor (IGBT) modules can enhance current-carrying capacity of power converter. However, due to parameter inconsistency of IGBT modules and different application conditions, these modules are prone to transient current imbalances, leading to significant differences in 'electrical-thermal' stress among devices, which compromises system safety and reliability. Traditional passive current-sharing approaches present limitations, such as large physical footprints, and complex tuning for multi-device parallel configurations. This article introduces an active transient current sharing scheme utilizing a printed circuit board Rogowski coil current sensor (PCB RCCS), which has advantages such as rapid adjustment, increased switching speed, accurate detection and feedback, compared with other active methods. Initially, the imbalance mechanism due to parasitic inductance variations is quantitatively analyzed. Then, an active gate driver (AGD) with current mirror compensation is developed. Furthermore, realtime current detection is achieved through the PCB RCCS for dynamic current sharing adjustment. Finally, A Buck converterbased experimental setup is designed for testing. The experimental results demonstrate that under various voltage levels and parasitic inductance discrepancies, the proposed AGD method can reach a current imbalance below 5% within 1us while accelerating switching speeds. Furthermore, it can reduce turn-on losses across parallel devices, improve consistency, and enhance reliability significantly. © 1986-2012 IEEE.

关键词： 永磁同步电机   矢量控制   仿真   DSP+FPGA  

摘要： 随着科学技术的发展，永磁同步电机已广泛应用在电动汽车、精密机床、航空航天等领域，矢量控制是目前最常用的控制策略。由于id=0的矢量控制策略只需控制转矩电流分量即可实现对电磁转矩的控制，因此该文采用该策略进行永磁同步电机矢量控制。在分析了永磁同步电机数学模型和控制原理的基础上，搭建了仿真模型，验证了id=0矢量控制策略的有效性。以DSP+FPGA为控制核心，设计了矢量控制系统的硬件和软件，并进行了实验验证。实际测量转速误差比例在1%以内，表明了所设计矢量控制系统具有良好的鲁棒性和稳定性。

关键词： 永磁同步电机   直接转矩   矢量控制   启动性能  

摘要： 针对永磁同步电机控制方式多样且控制效果不明确、不同控制方式速度波动差异较大、控制精度较低等问题，在研究了永磁同步电机驱动机理的基础上建立了永磁同步电机数学模型，搭建了永磁同步电机直接转矩控制和矢量控制物理模型，对比研究了2种控制方式的速度波动特性后得出：矢量控制的转矩和转速的响应特性比较平滑，在速度变化时波动较小，有利于对速度进行控制，矢量控制相比传统的直接转矩控制，转速和转矩的变化较快实现了短时间的速度提升，但存在驱动装置转矩脉动较大的问题，后期需要对永磁同步电机驱动控制方式进行优化。研究结论可以为后期提高永磁同步电机的驱动性能、开展永磁同步电机控制策略的有关研究提供参考。

关键词： 高频脉宽调制(PWM)   变频器   电气控制   现场可编程逻辑门阵列(FPGA)  

摘要： 高频脉宽调制(Pulse-Width Modulation，PWM)作为变频器控制的核心技术，在电气控制系统中的实现方式直接影响变频器的整体性能。基于此，分析高频PWM技术实现过程中的关键技术难点，并提出一种基于现场可编程逻辑门阵列(Field Programmable Gate Array，FPGA)的高频PWM技术实现方案。该方案为变频器高性能运行提供了技术支持，适用于精密控制要求高的工业场景。

关键词： PLC   PID调节   TIA Portal   变频器  

摘要： 为实现循环水的供水在不同用水量的情况下压力稳定，通过使用变频电机和PLC的PID控制调节，保证供水压力的稳定。使用压力变送器，检测系统管道中的压力。使用TIA Portal编写S7-1500CPU的相关程序，以设定的压力为控制变量，比较压力变送器传来的压力，通过PID控制的原理，控制变频器的输出频率，控制变频电机，达到设定的压力，并且保证压力的稳定性。通过Portal WinCC来控制电机的启停，或者选择是否使用PID调节，以及PID调节的设定压力。