Development and Prospect of Aircraft Power-by-wire Actuation Control Technology

Based on the development,evolution,and current status of aircraft power-by-wire actuation technology both domestically and internationally,this paper highlights the primary features of this technology and the crucial techniques linked to its core control functionalities.By considering the current trends in technology and future market demands,an outlook on the future progress of aircraft power-by-wire actuation control technology in China,including multi-disciplinary integration,cutting-edge research and design methodologies,and challenges and goals is also provided.

Design and Application of a Novel Wire Stripper

With the rapid development of the power industry,the work of the power electrician is becoming increasingly heavy,and the demand for improving work efficiency and reducing work intensity is becoming increasingly prominent.As one of the common tools of electric power,the design and application of wire stripper has an important influence on the efficiency and safety of electric power.This paper briefly analyzes the design and application of ceramic wire for electric power and electricians to provide a reference for the development of related fields.

COMPARISON AND EVALUATION OF CURRENT REFERENCE GENERATION STRATEGIES FOR ACTIVE POWER FILTERS IN THREE-PHASE FOUR-WIRE SYSTEMS

For three phase four-wire active power filters （APFs）, several typical power theories and corresponding current reference generation strategies are induced, p-q, d-q, unify power factor （UPF） and instantaneous active current （IAC） methods are analyzed and compared with each other. The interpretation of active and reactive currents in non-sinusoidal and unbalanced three-phase four-wire systems is given based on the generalized instantaneous reactive power theory. The performance and the characteristic are evaluated, and the application conditions of current reference generation strategies are concluded. Simulation results under different source voltages and loads verify the evaluation result.

An interconnecting bus power optimization method combining interconnect wire spacing with wire ordering

On-chip interconnect buses consume tens of percents of dynamic power in a nanometer scale integrated circuit and they will consume more power with the rapid scaling down of technology size and continuously rising clock frequency, therefore it is meaningful to lower the interconnecting bus power in design. In this paper, a simple yet accurate interconnect parasitic capacitance model is presented first and then, based on this model, a novel interconnecting bus optimization method is proposed. Wire spacing is a process for spacing wires for minimum dynamic power, while wire ordering is a process that searches for wire orders that maximally enhance it. The method, i.e., combining wire spacing with wire ordering, focuses on bus dynamic power optimization with a consideration of bus performance requirements. The optimization method is verified based on various nanometer technology parameters, showing that with 50% slack of routing space, 25.71% and 32.65% of power can be saved on average by the proposed optimization method for a global bus and an intermediate bus, respectively, under a 65-nm technology node, compared with 21.78% and 27.68% of power saved on average by uniform spacing technology. The proposed method is especially suitable for computer-aided design of nanometer scale on-chip buses.

Exact Solutions of a Power Law Fluid Model in Posttreatment Analysis of Wire Coating with Linearly Varying Boundary Temperature

In this paper, analysis of post-treatment of wire coating is presented. Coating material satisfies power law fluid model. Exact solutions for the velocity field, volume flow rate and average velocity are obtained. Moreover, the heat transfer results are presented for different cases of linearly varying on the boundaries. The variations of velocity, volume flow rate, radius of coated wire, shear rate and the force on the total wire are presented graphically and discussed.

Inverter power supply system for high-power twin-wire pulsed GMAW

A type of novel inverter power supply system for high-power twin-wire pulsed gas metal arc welding （GMAW） is presented mainly for dealing with the disadvantages of the conventional power supply for twin-wire pulsed GMA W of which the output power is generally difficult to increase due to limitations of the power of semiconductors and the power density of magnetic devices. In the power supplies for the master and slave arcs, the digital signal processor （DSP） TMS320F28335 is used to form the DSP- based synergic control system for parallel high-power pulsed GMA W, which achieves high-power output of two parallel inverters controlled by a single DSP ; master-slave communication is achieved by using e controller area network （eCAN）module of DSP, thas realizing anti-phase pulse output of high-power twin-wire pulsed GMA W and reducing the interference between twin arcs. The experiment results demonstrate that the designed inverter power supply system for high-power twin-wire pulsed GMAW can bring about high-power efficiency of welding, stable welding process and proper formation of welds.

Study on twin-wire pulsed MIG welding power supply based on DSP and CAN

A design proposal for twin-wire pulsed MIG welding power supply based on DSP （ digital signal processor） and CAN （ controller area network ） is put forward. By ase of the CAN bus, the synergic control between the master and slave power supplies can be realized. And in this way, their peak currents can be guaranteed to be alternative and the interference between the two arcs can be decreased efficiently. The hardware design, software design and relative tests are provided in this paper. Tests show that the power supply can meet the design requirements of twin-wire welding.

单向单线电能传输系统的电磁安全性

为解决单向单线电能传输系统的电磁安全性问题,首先搭建了单向单线电能传输系统和含有重要器官的人体模型;其次根据国内电磁场限值标准仿真研究了系统周围电磁场强度的限值范围,并探究了系统不同位置处的电磁场对体内重要器官的电场强度、磁场强度、电流密度和比吸收率(SAR值)最大值的影响程度;最后通过三维电磁场测量装置探测了单向单线电能传输实验系统周围的电磁场分布,得出了系统的限值距离,并与仿真限值距离进行了对比分析。结果表明:发射端和接收端的电磁场强度高于单导线周围的电磁场强度,右肾在发射端、接收端、单线处的的磁场强度分别为0.86、0.81和0.18 A/m;发射端和接收端对体内重要器官的影响程度明显大于单导线。实验与仿真所得的电磁场强度限值距离具有良好的一致性,证明了系统电磁安全性研究的正确性。

一种基于Unity3D技术的电力线路施工仿真系统

为研究电力线路施工耐张线夹压接仿真系统,首先,介绍了耐张线夹压接的基本原理,并讨论了电力线路施工耐张线夹压接仿真项目的实施过程;其次,详细分析了仿真项目的设计过程,包括仿真系统的硬件结构、仿真软件系统的设计和仿真结果的分析;最后,总结了仿真项目的优缺点,并指出仿真项目在电力线路施工中的应用价值。

一种接触网停电检修接地线接地可靠性检测方法

挂接地线是接触网停电检修作业的关键环节,为电力检修提供有效保障。为进一步加强电力检修作业的安全风险管控,针对在接触网停电检修作业时现有检测装置无法检测接地线是否可靠接地的问题,提出一种利用接触线上的残余电荷和感应电压来检测接地线是否可靠接地的方法。建立单线区段和复线区段停电检修挂接地线时的等效电路模型,并将接触线的残余电荷和“V”形天窗检修的感应电压作为等效激励源,对接地线电流进行理论计算;研制基于该文方法的接地线接地状态检测装置,用以判断接地线是否良好接地;通过所搭建的电流发生平台进行实验,并通过LoRa自组网与原有系统通信,在后台远程监测接地线的状态信息。实验结果验证了所提方法的可行性。

红外探测器芯片高可靠性键合工艺研究

金丝键合工艺广泛应用于红外探测器的封装环节。实验选用25μm金丝,基于正交试验法,根据键合拉力值确定键合的最佳工艺参数。通过优化超声压力、超声功率、超声时间及接触力等工艺参数组合,改善了键合引线的电气连接性能和连接强度,从而提高芯片系统的信号传输质量。提出的引线键合工艺参数组合适用于红外探测芯片的键合。

基于决策树的电网重要用户供电路径决策方法

广州等超大城市电网中110kV网架接线主要为3T接线,其运行方式多变,对电网的规划和运行有很大影响。超大城市电网中存在着大量的重要用户,其供电可靠性是安排电网运行方式的一个重要考虑因素。若安排的运行方式使得某些重要用户的供电路径汇集在同一元件,就会大大降低重要用户的供电可靠性。基于此,建立超大城市电网重要用户供电路径优化决策模型,以最小化电网中220kV线路的平均负载率为目标,要求系统的每个重要用户都要满足多个供电路径来自最少2个不同的220kV变电站。为了快速求解此混合整数非线性规划模型,引入多变量决策树将模型转化成一个整数非线性规划问题,再通过变量代换将其转化为一个整数线性规划问题,实现快速准确求解。最后,以广州电网实际数据为例,验证所提优化决策模型和求解方法的可行性与有效性。

高功率环境下多丝靶设计及运行考虑

多丝靶被广泛用于束流截面测量,但是常常因为束流功率沉积导致丝被损坏。为了研究不同束流参数以及丝靶设计与丝上温度和丝变形之间的关联,开发了基于后向欧拉法的自适应步长多丝靶温度数值模拟程序,并在离子源平台上开展了由温度导致的多丝靶变形实验。模拟和实验表明:在缺失恒定张力的情况下,温度是导致丝变形的主因。基于我们的模拟计算、实验验证以及操作经验,在丝温度低于1 300 K的情况下,拉丝采用锡焊固定的方式,其结构简单成本低;在高于1 300 K的情况下,采用弹簧张力的固定方式,可以提供恒定的张力,避免丝变形。

一种柔性接地线状态指示装置的设计与应用

提出了一种采用快速磁场检测方法的柔性接地线状态快速指示装置,并给出了其详细的设计和应用方法。在所设计的柔性接地线状态快速指示装置中,状态检测单元利用微型三维磁场实现实时高速磁场监测,状态报警单元通过3个阈值实现局部声光报警,而无线信号发送单元实现状态信息云显示。实验结果表明,所提出的柔性接地线状态快速指示装置可以有效地实现对接地线电流的智能监测,从而避免了接地装置误挂和接地不良造成的检修事故。

TO-3封装器件键合丝热机械可靠性与寿命预测

为解决双芯片功率放大器的过电应力烧毁问题,对器件电路进行改进并探究其可靠性。首先,重新设计和制备基片上金属带线,并进行温度循环与拉力检测试验;然后,基于有限元方法在温度循环载荷作用下对键合丝应力应变分布情况进行了分析,并通过Coffin-Manson模型对器件的疲劳寿命进行预测分析。结果表明,高温下应力降低了3.23 MPa,低温下应力下降了97.7 MPa。改进后的器件寿命提高了11.6%,且经历过温度循环后仍满足最小键合拉力极限值要求。该研究结果可为复杂键合丝结构及寿命预测提供参考。

三相四线三电平储能变流器中点平衡优化控制

传统三电平中点平衡控制方法在低不平衡度下对中点波动的抑制效果显著,然而在高不平衡度负载下有待改进。本文通过对不平衡程度进行实时检测分析,提出一种基于零电平分解的中点平衡优化控制方法。在不平衡程度达到临界阈值时,对零电平分解作用区域和分解量进行协调控制,使三电平三桥臂储能变流器在高不平衡度工况下的中点电压波动得到较好抑制。仿真实验结果验证了所提方法在各不平衡度负载工况下均具有良好的中点电位平衡能力。

弓网系统动态升弓问题关键影响因素研究

以铁路车辆系统中弓网系统为研究对象,针对列车运行过程中不同供电制式(AC/DC)切换时产生的动态升降弓问题,建立弓网系统升降弓接触动力学模型,并结合升降弓地面试验验证该模型的准确性。基于弓网系统升降弓接触动力学模型,利用正交实验方法研究影响升弓动力学的关键因素以及考虑接触线拉出值条件下动力学性能变化规律,得到了弓网系统合理的升弓参数范围。结果表明:升弓条件下,影响弓网动力学关键因素为弓头质量、升弓速度和接触线拉出值位置。

计及磁链和电流的PMSM DTC系统中功率器件键合线老化监测方法

在闭环控制系统中,基于电参数的功率器件老化监测方法是电力电子可靠性领域的难点之一。以永磁同步电机直接转矩控制系统为例,研究基于磁链相图和电流的功率逆变器中功率器件老化状态的在线监测方法。首先,分析功率器件老化的特征,得到键合线老化引起通态电阻增加的结论;其次,研究得到功率器件键合线老化与磁链相图、直轴电流和三相电流峰值变化的关系,进而提出功率器件键合线老化的监测方法;最后,通过多组仿真实验验证了基于磁链相图和电流的在线监测方法均可实现功率逆变器中功率器件键合线老化状态的在线监测。其中,基于磁链相图的在线监测方法需要系统磁链出现一些波动时才易观测,此时功率器件处于失效状态,该方法并不可取;而基于三相电流的监测方法能够更为精确地监测功率器件老化状况,效果更为优越。

基于平面微型线圈的单线电能传输系统研究

研究了由两个平面特斯拉线圈构成的微型单线电能传输(SWPT)系统,在Comsol软件中对该系统进行建模和参数设定,通过仿真实验,确定了平面特斯拉线圈在SWPT方向的可实现性。重点研究了SWPT系统在不同传输距离、不同传输频率情况下对传输效率的影响。并对SWPT系统模型各参数进行调整,通过改变模型初级和次级匝数,对系统传输效率进行分析。此处通过仿真实验,确定了SWPT系统最大传输效率下的各项系统参数,并通过实物实验验证了系统性能。

基于多阶段协同的电网厂站接线图智能识别

电网厂站接线图作为电力系统网络结构的重要数据,承载着电力设备运行的关键信息,在电网调度控制应用中具有重要作用。针对调度运维人员手动绘制方式导致工作繁琐、任务量大的问题,提出基于多阶段协同的电网厂站接线图智能识别方法,实现机器代人绘图。首先,采用切割检测增强对图元小目标的检测能力,通过形态特征提取及模糊比对处理实现图元方向识别;其次,基于随机粘贴原理增强文字识别模型的鲁棒性,基于知识融合技术提升图元文本匹配准确性;最后,基于连通域检测识别连接线,采用遍历筛选匹配图元与主接线的连接关系。实验结果表明,该方法对电网厂站接线图整体识别准确率在88%以上,将其应用变电站监控系统、换流站运行人员控制系统中,极大提升了作业人员构图建模效率。