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

The University Of Central Florida Board Of Trustees, Orlando FL

Investigators

Abstract

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.