A NEW CASCADE MULTILEVEL VOLTAGE SOURCE INVERTER FOR HIGH POWER APPLICATION OF FACTS

摘要

A cascade multilevel voltage source inverter is introduced to apply the static var compensator(SVC) for large scale power application. This cascade M-level inverter consists of (M-1)/2 single-phase full bridges. This inverter is suitable to the flexible ac transmission systems(FACTS) including SVC, series compensation and phase shifting. It can solve the problems of conventional transformer-based multipulse inverters and multilevel diode-clamped inverters. In this paper, the three phase SVC is modeled using the d-q transformation and analyzed completely. The control strategy which is based on this model is also proposed. From the simulation results, the validity of SVC with cascade multilevel inverter is shown for high power application.