拓扑变换

In order to eliminate the influence caused by the nonminimum phase characteristic of a common Boost DC／DC converter, Viswanathan K has proposed a novel tristate Boost DC／DC converter. For enhancing performance, the statespace averaging model of this converter was first presented in this paper. Due to the nonlinear nature in this model, an inputoutput feedback linearization technique was adopted, and a complete controllable linear system was obtained. Then a statefeedback control strategy was designed based on this linear system. Simulation results show that the proposed control strategy can assure constant output voltage in a wide range, so as to realize the stability of the system during large fluctuation of power supply and load disturbance. Good dynamic performance can also be achieved.

针对 Viswanathan K为消除普通BOOST DC／DC变换器的非最小相位特性而提出的三态Boost DC／DC变换器，为进一步提高这种电路拓扑的性能，在建立了变换器状态空间平均模型的基础上，针对其多变量、非线性特点，采用输入输出线性化将其转化为一个完全可控的线性系统，在此基础上应用现有成熟的线性控制策略进行了控制系统的设计，并且采用MATLAB进行仿真验证，结果表明：这种非线性控制策略可以确保输出电压在大范围内恒定可调，且即使存在大范围扰动(输入电压和负载变化均较大)的情况下，系统也可以确保稳定性和良好的动态性能。

Convex body; star body; cross i-section; Firey projection; Radon transform; Fourier transform of distribution; generalized intersection body; dual mixed volume; embedding in L_p

基础科学，数学，几何、拓扑凸体；星体； i-维中心截面； Radon变换；分布的Fourier变换；广义截面体；对偶混合体积；等距嵌入L_p

The topology of two-stage matrix converter given based on the concept of fictitious DC link of matrix converter and dual space vector modulation strategy of TSMC was studied.

在矩阵变换器虚拟直流环节的思想上，给出了双级矩阵变换器的电路拓扑，仿真研究了双级矩阵变换器的双空间矢量调制策略。

Due to the high reliability, high stability and low EMI criterions in auxiliary power supply systems, the half-bridge LLC resonant converter is selected for the front-end converter, the AC bus architecture and full-wave rectifier are as well utilized. The turns-ratio between the AC bus and load converter is 1:1. The effect of beads which are used in the load converters to the resonant circuit is analyzed.

根据辅助电源高可靠性、高稳定性、低电磁干扰、良好的高频隔离的要求，通过对不同拓扑类型的分析比较，选择半桥LLC谐振变换器作为前级变换器，交流母线和零式全波整流结构作为后级变换器，在母线和后级变换器的连接上采用1∶1的隔离变压器连接。

The theoretical analysis and simulation results of 1kW 40~60VDC/380VDC full-bridge Boost mode two-input DC-DC converter have shown that the converter has the advantages such as double isolation among multiple input sources and between output and input of the converter, simple topology, strong voltage matching ability, multiple input sources can supply the power simultaneously or individually, small input current ripple, high power density, high conversion efficiency, high reliability at short circuit, magnetic flux of high-frequency transformer easy to add up etc.

1kW 40～60VDC/380VDC全桥Boost型双输入直流变换器的理论分析和仿真结果表明，这种变换器具有多路输入源之间以及输出与输入源之间双隔离、电路拓扑简洁、电压匹配能力强、多路输入源可同时或分时供电、输入电流纹波小、功率密度高、变换效率高、负载短路时可靠性高、高频变压器磁通易于叠加等优点。

With regard to the converter of SRD system, the thesis firstly gives the study of the topology of converters that have the least main switches, and then lucubrates the single switch per phase converter with C-dump energy recovery circuit.

在功率变换器的优化设计方面，本文在对于具有最少开关数的功率变换器拓扑结构进行研究的基础上，深入研究了其中带存储电容斩波回收型功率变换器。

This paper will present a new diode-clamp cascade multilevel converter derived from these two topologies. The novel concept of the new diode-clamp cascade converter is based on the connection of multiple three-level diode-clamp converter modules.The multilevel waveform is synthesized by adding of each converter output voltage.

本文将结合这两种拓扑结构，研究了一种新型的二极管箝位级联多电平变换器，其思想是将数个二极管箝位变换器模型串联起来，其输出电压是通过合成每个二极管箝位变换器的输出电压而形成的。

In this paper, with the Buck circuit topology as the exampleof zero-transition soft-switching PWM DC/DC converters, theoperation principle and characteristics of the conventionalZVT-PWM converter and a novel two phase ZVT-PWM converter areanalyzed in-depth respectively.

文中以Buck型电路拓扑作为研究零过渡PWM软开关DC／DC变换器的代表，分别对传统ZVT-PWM变换器和一种新型的两相ZVT-PWM变换器的工作原理及特性进行了深入的分析。

The thesis mainly researches on the single phase AC/AC converter in the topologies including AC_Buck and AC_Cuk. Firstly, the operating principles of the two converters are analyzed in detail and the rules of their parameters design are educed; The commutation of their power switches which is the key of these topologies to realize is analyzed in detail and a feasible solution which can be named RCD-Commutation mode is presented and proved effectual by theory analyses and simulation results.

本文首先分析了AC_Buck变换器的变换原理，得出了电路参数设计准则；继而对电路实现的难点即功率管换流问题进行了深入分析，并得出了一种可行的解决方案即RCD换流方案；作为对简单拓扑单相直接AC/AC变换器控制策略的探索，本文以AC_Buck为平台，对电压单闭环瞬时值控制方案进行了研究，在理论分析和仿真研究的基础上设计并制作了一台采用RCD换流、电压单闭环瞬时值控制的AC_Buck变换器原理样机。

This circuit can be widely used in other topology, such as flyback converter, half bridge converter, full bridge converter and push-pull converter with synchronous rectifier.

这个电路可以推广到其他隔离变换器的拓扑中，如反激变换器同步整流、半桥变换器同步整流、全桥变换器同步整流和推挽变换器同步整流。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。