Multilevel converters control for renewable energy integration to the power grid

The paper deals with the multilevel converters control strategy for renewable energy resources integration in distribution grids. The proposed control scheme ensures the injection of the generated power in the distribution grid with fast dynamic response, while providing an additional active power filtering capability providing the required harmonic and reactive currents to the considered non-linear loads. The proposed control scheme is applicable to a general multilevel converter and to any types of the renewable energy resources. The control scheme is validated by means of simulations with a three-level diode-clamped converter which interfaces a wind power generation system to a distribution grid supplying non-linear loads. From extensive simulation results, high performance of this control strategy in renewable energy application is demonstrated with reduced total harmonic distortion, increased power factor and compensated load’s reactive powers.

Research highlights► In this paper, a control strategy of multilevel converters for integration of renewable energy resources into AC power grids is proposed. ► The proposed technique ensures the injection of the required harmonic and reactive power into distribution grid with fast dynamic response. ► The load voltage and grid current are in phase, and the unity mains PF stays at PCC, so DG can act as PF corrector and APF. ► The proposed control technique can be used in all types of multilevel converters topologies and all types of the renewable energy.