MULTI-PORT DC-DC AUTOTRANSFORMER AND APPLICATION THEREFOR

摘要

A multi-port DC-DC autotransformer, which is used for realizing interconnected transmission among a plurality of DC systems of different voltage levels. The autotransformer comprises 2N-1 current converters. The 2N-1 current converters are connected in series in sequence at a DC side and are connected to an AC line at an AC side, and the positive electrode of the ith current converter and the negative electrode of the (2N-i)th current converter of the 2N-1 current converters connected in series in sequence are respectively and correspondingly connected to the positive electrode and the negative electrode of the ith DC system, where N is the number of DC systems, and i is the serial number of the current converter. Further disclosed are a capacity design method for the current converters in the autotransformer and a control method for the autotransformer. The autotransformer enables most of the power transmitted among various DC systems to be directly transmitted through the electrical interconnection among the various DC systems without DC-AC-DC conversion, so that the rated voltage and the operating loss of the various current converters are greatly reduced, thereby reducing operating costs.