NEW HIGH-FREQUENCY AC DISTRIBUTED POWER SYSTEMS STRUCTURE WITH UNITY POWER FACTOR

近年来，直流分布式电源系统（DPS）已被广泛应用于大型计算机系统、通信系统、飞机、战斗机、军舰、相控阵雷达阵列和航天器，最近还被用于国际空间站的建设。 在当今的许多应用中，功率转换系统的理论问题和设计理念正在走向实践。 这些问题不仅包括提高效率，而且包括降低用于满足电子系统的总体性能要求的整个系统的成本和复杂性的方法。 本文的研究目标有三个方面：1）开发一种简化的电源系统，即高频交流分布式电源系统，以解决传统DC-DPS存在的主要问题。2)研究新的功率变换技术，大大简化了新型AC_DPS中功率因数前端变换器的设计; 3）发展新的复杂分布式电源系统建模技术。 该项目将侧重于调查和解决这些问题和其他问题。 还将通过仿真和实验方法对DC-DPS和AC-DPS进行比较研究，说明两种方法的优点和局限性。 本研究的另一个主要任务是采用与单开关PFC AC/DC变换器类似的思想开发单开关PFC逆变器，预期的研究成果包括 * 开发AC-DPS结构的建模技术，* 减小电力系统的尺寸和重量，降低成本，提高效率，并由于简化而提高可靠性。 此外，对单开关PFC逆变器的研究也将被推广到其他应用领域，如稳定、经济的PFC-AC电源和UPS等。

In recent years, DC distributed power systems (DPS) have been used extensively in mainframe computer systems, communication systems, aircraft, fighting jets, warships, phased-radar arrays and space vehicles, and lately been used in the construction of the international space station. In many of today's applications, theoretical issues and design philosophies of power conversion systems are finding their way into practice. These issues include not only improving efficiency, but ways to reduce cost and complexity of the over all system used to satisfy the electronic system's total performance requirements. The objectives of the proposed research are of three folds: 1) To develop a simplified power supply system, namely, high-frequency AC distributed power system to solve main problems of traditional DC-DPS. 2) To research new power conversion techniques that substantially simplfy the design of power factor front-end converters in new AC_DPS, and 3) To develop new modeling techniques for complex distributed power system.The main perceived technical limitations of the proposed AC-DPS are possible high EMI problem and analysis and post-regulator difficulities. This project will focus on investigation and resolving these issues and others. Also a comparative research between DC-DPS and AC-DPS will be conducted through simulation an experimental approaches, illustrating the merits and limitations of both approaches. Another main task on this study is to develop single switch PFC inverters employing similar idea as single switch PFC AC/DC converters.Expected research outcomes include *Development of modeling techniques for AC-DPS structure,* reduced power system size and lighter weight; lower cost; higher efficiency; and higher reliability due to simplification. In additional, the study on single switch PFC inverters will be brought into other applications such as stable cost-effective PFC-AC power supply and UPS etc.