ABSTRACT
This chapter discusses the function of a multifunctional bidirectional AC/DC T-type three-level converter for Super UPS. The bidirectional DC/AC converter has several operating modes such as dc voltage source mode, ac voltage source mode, power source mode. A control scheme for the multifunctional bidirectional AC/DC converter for different modes is studied. The magnitude and phase of three-phase current and voltage sinusoidal signals can be transformed into DC components by Park transformations. The Park transform block converts the time domain components of a three-phase system in an abc reference frame to direct, quadrature, and zero components in a rotating reference frame. The proposed control strategy was used to cover all of the required operating modes, such as AC voltage source mode, power source mode, and DC voltage source mode. The inner current loop can be used in each mode, while the current reference is determined by operating modes and outer loop.
