混合发电用多端口输入DC-DC变换器

为了提高能量的转换效率,提出了一种用于新能源混合发电的高低压多端口输入DC-DC变换器。首先,分析了多端口输入DC-DC变换器合成法则;接着,以罗氏变换器复举变换器和Buck变换器为合成单元,设计了高低压双输入DC-DC变换器的拓扑结构;然后,分析了电路的各种工作状态;最后,运用Matlab对设计的变换器进行仿真分析。仿真结果表明,所设计的变换器的各个输入口既可以独立也可以同时给负载供电。     

信息变换器设计精度的确定及其误差分配

正确地提出和设计信息变换器的精度是系统设计人员和电路设计人员都关心的一个问题。本文介绍用简便的查表法确定变换器的设计精度。设计精度确定后,重要的问题在于变换器的原理误差和工具误差的分配。从而根据分配的原理误差设计变换器的位数;根据分配的工具误差设计变换器中的模拟电路(非数字电路)。本文归纳了这两种误差的分配方法及其相互约制关系。     

半桥串并联谐振倍压变换器的分析与设计

介绍了半桥串并联谐振倍压变换器及其ZVS工作模式,分析和讨论了该变换器有关参数的设计方法,并给出了设计实例.     

单原边绕组双输入直流变换器的解耦控制

研究直流变换器的优化设计问题,对具有耦合系统的隔离型多输入变换器进行闭环设计,为了提高效率,减少漏感,需要运用合理的解耦方法去除环路之间的相互耦合.以双输入为例阐述了单原边绕组隔离型双输入buck变换器的双环控制策略及其闭环设计.运用空间状态平均法对变换器进行建模,得到系统的小信号数学模型控制对输出的传递函数矩阵,同时为了能够单独设计各个环路的控制器,通过对矩阵进行变换而加入了一个解耦网络.仿真结果证明,设计的闭环直流变换器是正确的.     

一种新型BUCK直流变换器的研究

文章提出了一种BUCK直流变换器的设计方法,利用状态空间平均法并结合欧拉公式建立了BUCK变换器的数学模型,设计了调节器,组建了闭环控制系统。实验结果验证了该设计方法的合理性。     

基于无源性的光伏DC/DC变换器的全局滑模控制

在光伏发电系统中,当其受环境影响时,系统输出电压及功率不稳定,主要由DC/DC变换器来实现其过程能量转换,因此研究高效的DC/DC变换器控制方法具有重要意义;引入了一种满足无源性的DC/DC变换器,同时引入一种新的指数趋近律,设计全局滑模控制策略;所设计控制方法不仅确保了系统状态的稳定性,而且提高了系统的鲁棒性,减弱了DC/DC变换器的抖动现象;并以双向Buck变换器为例,通过Matlab仿真验证了所设计控制器的有效性。     

基于MIT MRAC的Buck变换器电压控制仿真研究

为改善Buck变换器的控制性能,对基于模型参考自适应控制的Buck变换器电压控制方案进行了研究．首先基于小信号扰动法建立了Buck变换器的小信号解析模型;然后分析给出了自适应参考模型的设计依据,总结了设计步骤,并对自适应控制器的设计方法、关键参数的取值和影响进行了归纳;最后在Matlab/Simulink平台下搭建了频域和时域仿真模型,对文中重要结论进行了验证,证实了MIT MRAC用于Buck变换器控制的可行性和有效性．     

基于遗传算法的三节阻抗变换器设计

采用遗传算法对三节的理想传输线阻抗变换器进行优化设计,该传输线阻抗变换器能三个任意频率点对任意的纯电阻负载实现阻抗匹配.在给定条件下,首先对阻抗变换器构成的方程组进行预处理,并得到一个简化的方程组.再根据简化的方程组设计出适应度函数,通过遗传算法对简化方程进行数值求解,得到阻抗变换器的所有设计参数,并对所设计的阻抗变换器进行Ansoft Designer仿真分析.仿真结果显示该设计方法的正确性和有效性,该设计方法可用于实际的设计问题.     

Boost变换器的T-S模糊建模与控制

针对Boost变换器的非线性特性,考虑变换器参数不同情况对系统模型的影响,分别建立了参数确定和参数不确定条件下Boost变换器的等价T-S模糊模型。基于建立的等价T-S模糊模型,利用Lyapunov函数方法和线性矩阵不等式方法,给出了Boost变换器并行分配补偿模糊控制器的参数化设计方法。仿真结果表明,所建立的Boost变换器T-S模糊模型是可靠的,所设计的模糊控制器与模糊PI相比具有较强的鲁棒性和抗扰性。     

基于U模型的Buck变换器控制器设计

为了提高Buck变换器控制系统的设计精度和效率,对Buck变换器非线性建模及控制器的设计进行了研究。结合U模型不损失NARMAX模型非线性特性且易于设计控制器的特点,提出了一个基于输入输出数据的NARMAX建模方法,根据模型的残差,进行了相关性检验以验证模型的有效性。通过将NARMAX模型转化为U模型并基于U模型设计了Buck变换器的极点配置控制器。仿真结果显示,基于U模型的Buck变换器极点配置控制器在调节时间和超调量控制上优于传统的PID控制器。     

Development of a methodology for a simplified finite element model and optimum design

As computer power is increased, refined finite element models are employed for structural analysis and design. However, it is still difficult and expensive to make and use refined finite element models in the design stage. The refined models usually cause problems in the preliminary design where the design is frequently changed. Therefore, the development of a simplified finite element model is desirable for use in the preliminary design stage. This paper describes the methodology for the simplified model and its optimum design. A Goal programming algorithm is used for system identification to make the simplified model. The developed methodology consists of three phases such as simplification, design, and inverse process. The simplified finite element model is used for the design change and the changed design is recovered onto the original design. The presented methodology is verified through a few examples.     

基于SS序列集成电路布线技术

集成电路(IC)是在半导体基片上形成的完整的电子线路。当前芯片里的电路与系统日趋复杂,超大规模集成电路(VLSI)设计技术水平也在逐渐提高。VLSI设计中一般采用分级设计的方法。布图设计过程是整个VLSI分级设计中非常关键的步骤之一。基于Single-Sequence的集成电路布图就是在SS编解码的应用下对芯片中各单元的摆放进行优化从而达到芯片面积利用率最大化。本文重点介绍了在SS序列生成版图后各单元间连线的设计以及如何根据水平/垂直约束图提取版图中各单元的坐标。并根据要连模块的位置关系对其连线经过的模块进行有条件加线宽的处理。     

秩序与自由的博弈——低碳经济时代的工业设计之审视

低碳经济时代下,工业设计应该如何应对新的挑战呢?文章从哲学的角度出发,分析了设计的秩序和自由的博弈,寻求设计秩序理念和设计自由思想之间的一种平衡,从而重点阐述设计秩序观的理论,以此来协调现代设计观。作为一种新的设计思维方法,设计秩序观的提出具有重大的积极意义。设计秩序引导设计自由,设计自由激活设计秩序。秩序观是人类的既定要求,也是工业设计发展的最高层次。     

设计功能性与情感化的交替上升研究

研究设计的发展规律对于我们更好地认清设计的发展方向具有重要作用。本文以产品本身为对象,通过分析设计史,探究设计的发展规律。结果发现,工业设计的发展过程具有功能性与情感化设计交替上升的特点。结合这一规律的背景因素,得出了一些有关设计趋势的结论:在两者的同步行进时期,设计往往处于平稳发展阶段,发展的形式主要表现为小规模的量变;每当有一方异军突起时,设计往往处于迅猛发展阶段,容易发生推动性的质变。     

A novel inverse data driven modelling approach to performance-based building design during early stages

Energy analysis at the early stage of building design is a critical, yet difficult task in performance-based design. The difficulty arises from the complex, iterative, and uncertain nature of building design and the challenges of integration with well-posed energy assessment tools. The purpose of this article is to first review characteristics of performance-based design and establish requirements for a methodology that includes generating promising design alternatives, assessing the energy performance in tandem with the generation of alternatives, and choosing an alternative design solution with confidence. The study then proposes a novel systematic data-driven method, based on linear inverse modeling that generates plausible ranges for design parameters given a preferred energy target. The energy performance in this method is described as a linear function of the design parameters for a particular scenario of design. The application of the proposed method in a case study shows that it is capable of helping designers make informed decisions regarding energy performance iteratively and confidently at the early stages of building design.     

机械传动系统的自动布置设计

布置设计是连接产品概念设计与结构设计的桥梁,本文以龙门铣变速箱能ＣＡＤ系统的研究为背景,探讨了机械传动系统的计算机自动布置原理和方法,本文将产品布置设计划分为２个层次,提出了基于实例的定性布置和基于约束的参数布置相结合的布置设计求解框架。同时还提出了一种描述传动系统布置设计的表达模型－二维双向链表,该链表能统一描述与布置设计有关的信息,支持自顶向下的产品设计模式。     

Optimal design of metal seated ball valve mechanism

A seat is a device mounted in a valve. When a ball valve is in the closed position, the seat seals the ball valve. The seat is usually made from plastic or rubber, so it can be damaged by high pressure or high temperature environments. The objective of this study is to design a new metal seat mechanism for the ball valve. To design a new metal seat, there are four steps to the engineering design process: planning and clarifying the task; conceptual design; embodiment design; detailed design. Some useful tools from the Quality Function Deployment (QFD) technique and the Theory of Inventive Problem Solving (TRIZ) method are used in this design process. The design optimization is completed by the ANSYS package. The novel design of the metal-seated ball valve provides low torque, low wear and long life.     

An integrated component design approach to the development of a design information system for customer-oriented product design

In product design, the designer must draw upon many different types of information including both product-user requirements and design developments in related fields. As each designer has his/her own subjective opinion, an appropriate link between the user requirements and design features must be carefully developed to generate the most suitable design recommendation.The objective of this research is to develop a component design approach for the generation and evaluation of feasible design alternatives to help designers make the most effective design decisions. The development of the approach is based on the concept of component design and interaction links between user requirements and design output parameter values so that the design alternatives can be generated. A confidence interval for order statistics is then used to determine if enough unique feasible design alternatives have been generated. The research is presented in conjunction with a ballpoint pen design to demonstrate the feasibility and advantages of this approach.The results should provide designers with a useful method for the development of a design information system that will efficiently generate and evaluate a set of feasible design alternatives in product design process.