A direct power conversion topology for grid integrations of hybrid AC/DC resources

Abstract

This paper proposes a multiple-input versatile matrix converter (VMC) to integrate hybrid ac/dc energy resources and storages to a power grid. The VMC is developed based on the indirect matrix converter (IMC) with its six-switch voltage source converter replaced by a nine-switch topology. The nine-switch converter can provide six input terminals for the connections of one three-phase ac source plus three dc sources to the grid. The three-phase utility grid is connected to the VMC's current source side. This configuration allows the input ac/dc sources' voltages lower than the grid voltage. The control and modulation schemes are proposed to extract the commanded current from the input ac/dc sources to the grid and guarantee high quality ac/dc inputs and ac output current waveforms with unity power factors. The proposed modulation scheme for sinusoidal outputs of the VMC is mathematically proved. The experimental results are provided to validate the effectiveness of the control and modulation schemes for the proposed VMC.