Control design and experimental verification of a multi-function single-phase bidirectional PWM converter for renewable energy systems

Abstract

This paper proposes a multi-function control system for single-phase bidirectional PWM converters for renewable energy system applications. A common inner ac current-loop between the different modes helps to facilitate a seamless transition between them, where several individually designed outer loops alternatively perform the different regulation tasks, namely ac voltage, dc voltage, and dc current. The frequency-response based design procedure for the proposed control system is presented in detail for all the converter operating modes, and its performance is verified experimentally using a DSP-controlled 7 kW 120 V ac — 300 V dc laboratory prototype.