Parallel single-phase ac-dc-ac shared-leg converters: Modelling, control and analysis

Reversible single-phase to single-phase dc-link converters are proposed and analyzed in this paper. They are composed of paralleled rectifiers and inverters sharing one or two legs with one or two dc-links. Modelling and a control strategy of the systems including circulating currents are developed. Compared to the conventional single-phase to single-phase dc-link converter, the proposed topologies permit to reduce: (i) the current and power ratings of the power switches, (ii) the harmonic distortion, and (iii) the dc-link capacitor losses. Additionally, the semiconductor losses of the proposed converters are smaller than that of the conventional one. Simulated and experimental results are also presented to demonstrate the viability of the proposed circuits.