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关键词： 轴向磁场磁通切换永磁电动机   齿槽转矩   转矩脉动   系统效率   自适应扩展卡尔曼滤波器   扰动补偿   矢量控制   谐波电流注入法  

摘要： 为了抑制轴向磁场磁通切换永磁(axial field flux-switching permanent magnet,AFFSPM)电动机齿槽转矩引起的转矩脉动,提出一种基于自适应扩展卡尔曼滤波器的齿槽转矩抑制方法.该方法根据齿槽转矩分析结果,以及AFFSPM电动机数学模型和损耗模型,将齿槽转矩引起的系统转矩脉动作为扩展状态变量,与电流环的反馈电流一起构造系统扩张状态空间方程.在状态估计过程中引入了遗忘因子,提高观测精度和速度.与基于谐波电流注入法抑制齿槽转矩的控制方法进行了控制性能和突变工况对比.结果表明:所提出控制方法在低速时转矩脉动降低了43.5%,电损耗降低了14.8%,能更有效抑制齿槽转矩脉动和提高系统效率.

关键词： IGBT module   Bond wire aging   Gate voltage   Ringing   Frequency characteristics  

摘要： Aging monitoring of IGBT modules in power converters not only effectively improves system operational reliability, but also significantly reduces maintenance costs. This paper proposes a novel method for monitoring bond wire aging in IGBT modules based on the ringing frequency characteristics of the turn-on gate voltage. Initially, based on the turn-on characteristics of IGBT module and equivalent circuit model, this paper systematically analyzes the reasons for turn-on gate voltage ringing, and points out that the ringing frequency can be used as an indicator to reflect the aging of bond wires. Then, experimental validation of the proposed monitoring strategy was conducted on a buck converter testbed, with comprehensive analysis of operational impacts induced by DC-link voltage variations, gate resistance selection, and junction temperature fluctuations. Finally, this work presents a bond wire degradation monitoring scheme based on gate ringing frequency threshold analysis. The experimental results show that the voltage ringing frequency at the gate Miller plateau of the IGBT module decreases with the aging of the bond wires. The method is non-invasive, and achieves decoupling of the junction temperature using a set threshold.

关键词： Logic gates   Temperature measurement   Temperature sensors   Insulated gate bipolar transistors   Monitoring   Junctions   Sensitivity   Capacitors   Current transformers   High-voltage techniques   Gate electric quantities   insulated gate bipolar translators (IGBTs)   junction temperature monitoring   thermo-sensitive electrical parameter (TSEP)  

摘要： The junction temperature is a significant indicator for evaluating the reliability of insulated gate bipolar transistors (IGBTs). In this article, in order to realize noninvasive and simple temperature monitoring, the gate electric quantities are adopted as the thermo-sensitive electrical parameter (TSEP), and the proposed method can realize high sensitivity for monitoring junction temperature of IGBTs. First, the gate electric quantities is adopted and studied as the TSEP. The temperature relationship and sensitivity of the gate electric quantities are analyzed. And then, a sampling circuit of the gate current has been designed with a current transformer (CT) in gate-driver circuit. In addition, the thermo-sensitivity enhanced method of the measured results is proposed by regulating the output resistor of CT. Finally, the inverter experimental platform is developed to verify the correctness of theoretical analysis. Compared with conventional schemes, the proposed gate electric quantities method can achieve higher 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.

关键词： Feature extraction   Wires   Bonding   Data mining   Monitoring   Eigenvalues and eigenfunctions   Degradation   Switches   Insulated gate bipolar transistors   Covariance matrices   Bonding wire   condition classification   feature extraction   insulated gate bipolar transistor (IGBT)   random forest (RF)   random matrix theory (RMT)  

摘要： As a vulnerable part of insulated gate bipolar transistor, condition monitoring of bonding wires can detect potential faults at an early stage, thus avoiding threats to system safety. In this article, we propose a monitoring method that combines feature extraction and condition classification, using multicycle and low-frequency operation data to construct a high-dimensional matrix, analyzing spectral properties and constructing linear eigenvalue statistics based on random matrix theory to extract potential information. An optimized random forest (RF) model using cross validation and particle swarm optimization algorithms ensures that the classification task benefits from the selected features and the optimized model. The results show that the feature extraction method can be highly adaptable to high-frequency action switches and is able to identify latent patterns. The optimized RF model accurately classifies early bond wire breakage states, requires a lower sampling frequency than traditional methods, and still performs well in unbalanced data.

关键词： Voltage   Topology   Logic gates   Circuit breakers   Switches   Resistors   Gate drivers   Capacitors   Energy storage   Periodic structures   IGBT   single drive   solid-state circuit breaker  

摘要： Solid-state dc circuit breaker (SSCB) has become a key component for fast fault isolation in high-voltage dc systems. However, their effectiveness often relies on complex series and parallel connections of numerous switches. To address the low flexibility and redundancies problems inherent in conventional circuit breakers, this article proposes a single-drive series-parallel insulated gate bipolar transistors (IGBTs) all-solid-state dc circuit breaker component (SCBC). The innovative approach can precisely control multiple series and parallel IGBTs by using only one gate driver and a small number of passive components. In this novel configuration, a shutdown signal triggers the first-stage IGBTs. Once activated, the energy storage capacitor causes the subsequent IGBTs to shut down continuously. In SCBC, the main switches are connected in series and parallel, the breaking current capability is improved. In particular, the componentized design concept makes the topology is extensible and enhances the flexibility of SSCBs. Finally, the operating principle and design guidelines of SCBC are illustrated in detail through the creation of a mathematical model and topology, and their effectiveness is demonstrated through simulation and experimentation.

关键词： Logic gates   Wire   Voltage measurement   Monitoring   Insulated gate bipolar transistors   Capacitance   Circuits   Threshold voltage   Temperature measurement   Switches   Chip open-circuit failure   health condition monitoring   multichip insulated gate bipolar transistor (mIGBT) modules   precharge time of gate voltage  

摘要： Multichip insulated gate bipolar transistor (mIGBT) modules are the optimal solution for achieving high current and power capacity in industrial applications. Monitoring chip open-circuit failure caused by emitter bond wire lift-off is essential for enhancing the robustness and reliability of converters. This article proposes an in situ monitoring method for chip open-circuit failure in mIGBT modules, which is based on the precharge time of gate voltage (t(PG)). Theoretical analysis is conducted to derive t(PG) as a health sensitive parameter. The sampling and diagnostic circuits are designed in detail, and the effectiveness of the proposed method is validated through double pulse and converter tests. Experimental results indicate that when chip open-circuit failure occurs, t(PG) significantly decreases. The proposed method is independent of bus voltage and load current, and exhibits high immunity to junction temperature variations. It requires only measuring variations in gate voltage. Furthermore, this method provides a solution for monitoring and diagnosing of chip open-circuit failure without requiring microprocessor involvement, enabling plug-and-play functionality or integration into the gate driver circuit. The proposed method presents high safety, low invasiveness, and ease of implementation.

关键词： 外肢体   人机协同   步行速度估算   模型预测控制   最优控制  

摘要： 针对平坦地形下人与外肢体协同行走的控制问题，本研究提出一种双足轮腿式外肢体的运动跟踪控制策略。首先，采用零速检测法实现人体步态相位划分，并基于人体质心运动学模型在支撑相期间实时估算步行速度。结合牛顿-欧拉法建立人体与外肢体的耦合动力学模型。系统状态向量包括外肢体前进速度、前向位移、俯仰角、俯仰角速度以及弹簧阻尼器状态，控制输入为轮毂电机的驱动力矩。设计无约束模型预测控制器，构造包含状态跟踪误差与控制输入变化率的二次型性能指标函数，利用二次规划求解器在线优化控制序列。实验结果表明，该控制策略有效抑制了人机交互中的干扰，耦合力均方根误差由15 N显著下降至5 N，降低幅度达65%；外肢体俯仰角跟踪误差稳定在0.02–0.16 rad之间，相较于无控制状态下降75%。

关键词： IGBT   击穿特性   输出特性   转移特性   关断损耗  

摘要： 为了优化载流子存储沟槽栅双极晶体管（CSTBT）的性能，对CSTBT结构进行了电学特性仿真，首先通过Sentaurus TCAD软件对比了T-IGBT和CSTBT的击穿特性、输出特性以及关断特性，最后研究了CSTBT N-drift区掺杂和厚度、P-base区掺杂和CSL掺杂对器件的击穿特性、转移特性以及输出特性的影响。结果表明，相较于T-IGBT，优化前的CSTBT的击穿电压提升了3.4%，正向导通压降减小了20.9%，关断损耗几乎一致；对于优化后的CSTBT，当N-drift区厚度为158 μm，N-drift区掺杂为7×1013cm-3，P-base区掺杂为3×1017cm-3，CSL掺杂为1×1016cm-3时，器件的BV为1959 V，提升了22%；Von为1.14 V，降低了43%；Vth为7.6 V。

关键词： 压接型IGBT   测试平台   K系数   压力   测试温度  

摘要： 压接型IGBT模块在高压直流输电等场合广泛应用，但其在大电流运行中的结温升高对器件可靠性有显著影响，因此准确监测结温是保障压接模块长期稳定运行的关键。针对传统方法在测试环境控制与测量结温方面存在的局限，本文以传统的基于电学法的K系数测试技术为基础，设计了一套集成压力监控与光纤测温的测试平台。通过以小电流下的集-射极电压降作为温敏电参数，对两种型号的压接型IGBT模块子单元开展实验研究，获得了结温与电压降的线性关系，并分析了电流、压力及温度历程方向等因素的影响。结果表明，在保证子单元完全开启的条件下，压力变化对K系数影响较小，而温度历程方向对结果一致性具有更显著作用。本研究验证了所建平台的有效性，为后续模块级K系数测试及结温监测提供了参考。

关键词： 采摘机器人   动力学模型   最优控制   遗传算法   鲁棒性分析  

摘要： 复杂地形下机器人的稳定性始终是制约其推广应用的核心问题。本研究以轮式采摘机器人为目标对象，设计半主动式悬挂系统增强其稳定性。基于运动学方法建立了机器人系统的动力学模型，设计LQR控制器，以机器人垂向加速度，悬挂动位移和轮胎动位移为目标，采用遗传算法优化加权系数，确定最优控制策略。研究中对遗传算法中不同参数对优化结果的影响进行了探讨，表明种群个数对控制器效果具有重要影响。在最优控制策略下，进一步对比了不同路面特征下的机器人响应特性，结果表明设计的控制器对不同路面具有较好的适用性。最后对控制系统的鲁棒性进行了分析，在结构参数变化时控制系统能够起到正常的控制作用。研究结果对改善移动机器人不同路面行驶的稳定性具有重要参考意义。