Multiphase Isolated DC-DC Converter With Combined Magnetic Elements

When designing multiphase DC-DC converters, due to the increase in the number of magnetic elements with an increase in the number of switching phases, the weight and size indicator of the product as a whole becomes relevant. The topology of a multi-phase DC-DC boost converter with a reduced number of magnetic elements is proposed by combining an input storage inductor and a transformer in one structural element. Possible combinations of states are investigated on the example of a 3-phase converter and the preservation of the positive qualities of multi-phase converters is shown. Theoretical calculations of the overall power of magnetic elements have been carried out, which show a decrease in the weight and size index of magnetic elements relative to the classical 3-phase converter. With a fixed value of the supply voltage, the decrease in the weight and size indicator is 34.8%, and with a twofold change, the indicator increases to 43.5%. The practical implementation of the proposed topology of a 3-phase converter showed a decrease in the weight and size index of magnetic elements by 33%.