Dynamic Modeling and Design of Distributed Power Systems with Power Factor Correction

随着功率开关器件技术的进步，为各种工业和航空航天应用设计更小尺寸和更轻重量的功率电子系统的驱动力将继续增加。 此外，随着非线性负载电源继续在电力电子系统中激增，密集的研究和开发工作也将继续增长，以便开发新的功率因数校正（PFC）技术来提高电能质量和效率。 这项工作将继续下去，特别是随着政府法规变得越来越严格。拟议的研究的目标是解决一些关键问题的分析和。具有功率因数校正的分布式电源系统（DPS）的设计。 这些问题的问题和挑战包括PFC变换器的拓扑结构，建模，DPS系统的稳定性等，在这个项目中，我们还将研究新的电流控制方法，用于稳定输出，并提供相等的负载电流并联连接的系统共享。 所研究的变换器可用于离线应用，以提高功率因数校正。 本项目将采用有源功率因数校正技术来构建并联系统，并仍能实现接近单位功率因数。 与传统方法不同，新开发的转换器系列将进一步消除线路电流失真，并具有接近单位功率因数。 最后，我们将根据分布式电源系统中功率因数校正电路的概念设计，构建一个可工作的硬件单元。在项目的两年期间，我们将进行以下主要工作：1）研究传统建模技术及其在AC/DC功率因数校正变换器中的应用局限性，2）针对AC/DC功率因数校正变换器族，重点研究了单级单开关拓扑的建模方法; 3）利用所建立的模型，对选定的单级PFC变换器进行了小信号、大信号分析和仿真，搭建硬件平台并对所开发的模型进行实验验证; 4）从可靠性、瞬时性、共享性、模块间交互性等方面对各种并行方案进行研究和比较，5）采用可行的并联方案将多个前端PFC变换器和DC/DC负载变换器集成在一起形成分布式电源系统，最后，6）通过对同一分布式电源系统进行仿真，对各种简化系统模型进行对比研究，对简化模型进行修正和完善，并进行DPS分析和仿真的硬件验证。开发的控制概念将被说明为一个模块的两个并联连接的交流-直流单开关功率因数连接转换器。 仿真结果表明，当涉及到系统的稳定性和系统性能的改进空间是必要的。

As power switching device technology advances, the drive for designing smaller-size and lighter-weight power electronic systems for various industrial and aerospace applications will continue to increase. Moreover, as nonlinear load power supplies continue to proliferate power electronic systems, intensive research and development efforts will also continue to grow in order to develop new Power Factor Correction (PFC) technology to improve power quality and efficiency. This effort will continue especially with government regulations become more and more stringent.The objective of the proposed research is to address some of the critical issues in the analysis and. design of distributed power supply systems (DPS) with power factor corrections. Problems and challenges of these issues include PFC converter topology, modeling, stability of DPS systems, etc. In this project, we will also investigate new current control methods used to stabilize the output and provide equal load current sharing in parallel connected systems. The converters that are investigated here can be used in off-line application to improve power factor correction. Active power factor correction technique will be used in this project to construct parallel-connected systems and still achieve near unity power factor. Unlike the traditional approach, the newly developed family of converters will result in further elimination of line current distortion, with near unity power factor. Finally, a working hardware unit will be constructed based on the conceptual designs of the power factor correction circuits used in distributed power systems.During the project's two-year period, we will carry out the following major tasks: 1) Investigate the conventional modeling techniques and their limitations for the applications in ac/dc power factor correction converters, 2) develop new modeling methodology for family of ac/dc power factor correction converters, focusing on single-stage single-switch topologies, 3) carry out small-signal, large-signal analysis and simulation on selected single PFC converters by using the developed models, set-up hardware platform and perform experimental verification for developed models, 4) investigate and compare various parallel schemes with respect to reliability, transient and sharing performance and interaction among modules, 5) integrate several front-end PFC converters and DC/DC load converters to form distributed power system using viable paralleling schemes, and finally, 6) conduct comparative study for various simplified system models by simulating the same distributed power system to modify and refine simplified model, and perform hardware verification for DPS analysis and simulation.The control concepts developed will be illustrated for a module of two-parallel connected ac-dc single switch power factor connection converters. The simulation results show that room for improvement is necessary when it comes to system stability and system performance.