Advances in modeling and applications of three-phase power converters.

摘要

The open-access power market requires the power transmission and distribution to be more reliable, flexible, and economical. Flexible AC Transmission Systems (FACTS) is the key technology to achieve these objectives. Power converters serve as the building blocks for almost all of the recently emerged FACTS controllers. As a result, research on the topology, modeling, and control of the power converters will be essential in the future developments in the FACTS area.; In the first part of this thesis, a novel modeling technique, based on the nonlinear transformation, is used to derive linear models for three-phase PWM power converters, that are independent of the operating point. Based on the new models, linear controllers are designed to achieve fast and decoupled control, over the whole range of operation. In the second part of the thesis, new topologies for FACTS controllers, based on the current-source converter, are proposed. The new modeling and control technique is applied to STATCOM (STATic synchronous COMpensator). Also, an alternate modeling and control technique is applied to SSSC (Static Synchronous Series Compensator).; The validity of the proposed modeling technique, and the performance of the current-source converter-based STATCOM and SSSC, are verified by the simulation results obtained from the PSCAD/EMTDC package, and the experimental results obtained from a laboratory prototype, with a DSP-based controller.