Modulação descontínua para conversores com pernas em paralelo magneticamente acopladas

Abstract

Aiming to contribute to modulation strategies for converters with magnetically coupled parallel legs, a new strategy of discontinuous carrier modulation is developed for this class of converters. To clarify the strong points and limitations of the proposed modulation, an analysis between the discontinuous modulation and the phase shift carrier modulation with geometric approach is presented. Therefore, the synthesized multilevel equivalent output line voltage, the circulating currents between the parallel legs of the converter and the voltage and current THDs are investigated and compared in detail. First, the details of the geometric modulation for converters with parallel legs are presented. Next, the development of discontinuous carrier modulation by state machines is presented. The proposed modulation shows good results when compared to the phase shift carrier modulation strategy for interleaved converters. Experimental and simulation results show characteristics such as: (i) Limitation of circulating current; (ii) Reduction of THD of the output current; (iii) Reduction of current in switches; (iv) Reduction in the stress of the switching of switches; (v) Ease implementation are achieved by this modulation strategy.