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关键词： 自适应动态规划   非对称输入约束   分散控制   神经网络   最优控制   状态观测器   未知不匹配互联  

摘要： 基于自适应动态规划算法研究了具有未知不匹配互联和非对称输入约束的连续时间非线性系统分散控制问题.首先,根据孤立子系统的局部状态和耦合子系统的参考状态,采用径向基函数神经网络近似未知互连项,从而消除了互联项满足匹配条件且存在上界的常见假设.然后,基于自适应评判框架,将分散最优控制器设计问题转化为一系列子系统非对称约束下局部最优控制器设计问题.利用Lyapunov稳定性定理,证明了不对称输入约束控制器能够迅速地镇定大规模分散系统.其中,引入状态观测器估计大规模非线性互联子系统状态并保证了观测误差满足一致最终有界.另外,利用评判神经网络近似改进后的代价函数,以近似求解Hamilton–Jacobi–Bellman方程,获得满足非对称输入约束的最优分散控制策略.基于评判网络权值更新规则,通过选择合适的Lyapunov函数保证了权值近似误差满足一致最终有界.最后,通过仿真实例验证了该算法的有效性,并通过与未改进代价函数的传统方法对比,体现了该方法的先进性.

关键词： 电动轮自卸车   直接转矩控制   纯电动力   驱动系统   绿色矿山  

摘要： 传统的机械传动矿车碳排放较高,驱动系统结构复杂,在高海拔低温环境中降功率现象严重,运营成本较高。针对某100 t机械传动自卸车的驱动系统,研究了其驱动系统的组成及特点;提出了一种包括主牵引传动+辅助系统的驱动系统和控制系统方案并对控制算法进行了描述。主牵引系统采用793 kWh动力电池作为动力源,结合直接转矩控制算法驱动1台680 kW的主牵引电机,辅助系统的两个逆变模块、DC/DC模块和电池散热机组可以分别驱动转向和举升液压泵电机,为整车空调和散热风机提供电源以及为动力电池提供散热电源;对整车进行海拔5500 m、-30℃的满载工况下的制动/牵引转换、重载上坡起步、重载上坡行驶、重载下坡电制动等矿山现场装载试验,运行情况稳定可靠,降低运营成本93%,累计运行4230 h,累计运行里程4238 km。该驱动系统结构简单,回收的制动能量提高了系统能效,减少了碳排放,促进了绿色矿山的发展。

关键词： Optimal control   Competitive species   Pollution   Maximum principle  

摘要： In the paper,we study an optimal control for a system representing a competitive species model with fertility and mortality depending on a weighted size in a polluted environment.A fixed point theorem is applied to obtain the existence and uniqueness exhibited by a non-negative solution of above mentioned model.A maximum principle helps to carefully verify the existence of the optimal control policy,and tangent-normal cone techniques help to obtain the optimal condition specific to control issue.

关键词： IGBT cooling   Manifold microchannel heat sink   Physics-informed neural network   Numerical simulation  

摘要： This study explores the application of Physics-Informed Neural Networks (PINNs) in modeling fluid flow and heat transfer dynamics within intricate geometric configurations, focusing on manifold microchannel (MMC) heat sinks designed for efficient high-power IGBT cooling. A deep neural network architecture comprising two subPINNs, one for flow dynamics and another for thermal behavior, is developed, each initialized with a sine activation function to capture high-order derivatives and address the vanishing gradient problem. Comparisons between PINN and CFD simulations reveal close agreement, with both methods showing an increase in pressure drop and a decrease in temperatures as inlet velocity increases. Discrepancies arise in scenarios with rapid flow pattern or gradient changes, highlighting PINNs' sensitivity to geometric complexity and numerical stability. Overall, this study underscores PINNs' potential as a promising tool for advancing thermal management strategies across various engineering applications.

关键词： ETM coupling field   Junction temperature   PINN   Numerical calculation   Data-model fusion  

摘要： The electric-thermal-mechanical (ETM) multi-physics coupling fields commonly exists in power electronic devices such as insulate-gate bipolar transistor (IGBT), which dominates the evolution of key state variables inside the components. Among them, the junction e and electric potential of the chip layer, as the dependent variables of various lifetime physical models, directly affect its remaining service life and health status. Aiming at the problem that the key physical variables inside the IGBT are difficult to monitor and predict, this paper first integrates and establishes the ETM coupling partial differential equations (PDEs) inside the IGBT, then accordingly proposes an accurate numerical calculation method for coupled physical fields based on ETM-physicsinformed neural networks (ETM-PINN).Through relevant simulation verification, it can not only realize the numerical calculation of the chip layer junction temperature and electric potential field without data, but also perform multi-physics predictive calculation with reduced accuracy in the absence of the key coefficients in PDEs. In the presence of additional physical field data, it can also perform data-model fusion calculations to further improve the solution accuracy.

关键词： 绝缘栅双极型晶体管   浮空P区   高击穿   低损耗  

摘要： 为实现更高的能源转换效率，优化IGBT的导通压降(Vcesat)和关断损耗(Eoff)之间的折中关系，同时提高IGBT的阻断特性，提出了一种集电极浮空P区结构的绝缘栅双极型晶体管（Collector Floating P-layer IGBT,CFP-IGBT），通过在集电极区域实施多次P型杂质离子注入形成P柱，P柱可以辅助耗尽集电极侧的漂移区内的电荷，进而提高正向阻断下集电极侧的电场强度，获得更高的击穿能力；在器件关断阶段，P柱减少了电场扩展后剩余的非耗尽区的宽度和过剩载流子的数量，从而降低关断损耗，减少拖尾电流，进而有效改善了导通压降与关断损耗的折中关系。实验仿真结果显示，CFP-IGBT相较于传统沟槽栅场截止IGBT（Field Stop,FSIGBT）的耐压能力提升了10%，关断损耗则降低了15%，在相同击穿电压1 400 V下，CFP-IGBT的晶圆可以进一步减薄10%厚度，在导通压降为1.5V下，其关断损耗可实现降低超过50%。

关键词： IGBT   状态监测   频谱   键合线老化   栅氧化层老化  

摘要： IGBT的健康监测对于系统的正常运行至关重要，而当前的研究主要面向单一老化，多种老化叠加会导致一些监测方法适用性低，容易误动作，对于多老化状态判定和区分的研究还有很多不足。由于集射电压(VCE)频谱中含有丰富的信息，不同老化会对其产生不同影响，因此提出一种基于VCE频谱的键合线老化和栅极老化的判定和区分方法。首先，分析键合线和栅极老化对电压开关波形的影响。然后，对开关电压波形FFT并进行频谱分析，探究不同老化对频谱产生影响，由此进行老化判定和区分。最后，搭建电路进行实验验证，并分析不同工况对该方法的影响。实验结果表明键合线老化和栅极老化均会使高频段幅值增大，所提方法可以有效区分不同老化形式。

关键词： 策略   通讯   流程   CAN  

摘要： 为提高控制系统通讯的可靠性,从中压水冷变频器控制系统架构及通讯分层结构入手,开展通讯策略研究。给出控制系统通讯建立、信息传递、指令和参数处理等过程的策略和方式。通过提高控制系统的可靠性,增加了变频器运行的安全性、稳定性。

关键词： 模糊控制   PID控制   电机调速系统   线性系统   交通运输   直接转矩控制   背景与意义   矢量控制  

摘要： 一、基于模糊控制的电机调速系统设计与优化引言与背景。(一)研究背景与意义。电机调速系统在现代工业、交通运输、家用电器等领域中扮演了至关重要的角色。传统的电机调速方法如PID控制、矢量控制和直接转矩控制,在处理简单、线性系统时表现出色。

关键词： Insulated gate bipolar transistors (IGBT)  

摘要： Insulated-gate bipolar transistor (IGBT) modules are extensively utilized in high-speed trains, ships, and electric vehicles. Compared to those used in power systems, IGBT modules in these applications are more susceptible to vibration effects on their reliability. This paper proposes a multi-physics field simulation method and a lifetime model for IGBT modules to assess the impact of different vibration directions on solder layer fatigue. Initially, a multi-physics field model of the IGBT module is developed, incorporating electrical, thermal, mechanical, and vibration coupling. The effectiveness of this multi-physics simulation model is verified by an experimental platform. Subsequently, the influence of different vibration directions on solder layer fatigue in the IGBT module is analysed, and a life model of the IGBT is proposed through simulation. Finally, a power cycling with a vibration environment experimental platform is established to validate the effect of vibration on solder layer fatigue in the IGBT module. The simulation and experimental results indicate that vertical vibration accelerates the solder layer fatigue of IGBT modules, and the lifetime of an IGBT module operating under vertical vibration at 30 Hz is about 15 % shorter than that of an IGBT module operating under power cycling alone. The error between the calculated results of the solder layer failure and the experimental result is © 2024 The Authors