Converters used in HVDC systems. The study of switching

This paper deals with DC - AC static converter systems, of very high voltages and currents, used for electricity power transmission. It has been analyzed three types of converters: with forced commutation, with commutation from load and the solution proposed by the authors. There are shown the advantages in hybrid switching converters, which in essence connect, constructive and as principle of operation, the advantages of the two known conversion systems. The analysis of the benefits of the proposed solution is done by comparing the circulating power of assets and also by analyzing the power factor. Not in the last, must be mentioned the paper contribution to the development of the theoretical base design for switching converters with hybrid commutation.