Adaptive saturation for a multifunctional three-phase photovoltaic inverter

This paper presents an inverter control scheme, based on proportional-resonant controllers, where the inverter works in multifunctional operation. In this case, the reactive power and harmonic compensation of the load are ancillary services. A resonant control is implemented in stationary reference frame (αβ), where is not necessary the use of a phase-locked loop (PLL). The instantaneous power theory (IPT) is used to detect the harmonic current and reactive power of the load. These components are used as references in the inverter control strategy. Most important fact and less related in literature is the inverter current limitation strategy. Thus, this work introduces a dynamic saturation scheme for a multifunctional three-phase inverter. This strategy possibilities partial or total reactive power and harmonic current compensation without injection of low order harmonics, ensuring that the inverter current does not exceeds the rated current.