Modeling and performance of a static frequency converter starting a 300 MVA synchronous machine

This paper presents a study of the dynamic behavior of a static frequency converter driving a 300 MVA synchronous generator which is used in a pumped storage power plant of Taiwan Power Company. The static frequency converter, which consists of a three-phase AC/DC phase converter, a filtering inductance, and a six-step current-source inverter, is used to start a 300 MVA synchronous machine. In this paper, first the mathematical model of the whole system which consists of a synchronous machine, a static frequency converter, a microprocessor, and sensors is established. Then, the control method of the static frequency converter based on field oriented control is presented. Next, a filter circuit has been designed to reduce the harmonics of the AC source. By using this filter, the harmonics can be effectively reduced. Finally, some computer simulated and experimental results are shown to verify the theoretical analysis. This paper presents a new direction in the use of advanced power electronic technology to drive a very large synchronous machine.