DC-DC converters for electric and hybrid vehicles with multi-voltage levels

摘要

The invention relates to a DC-DC converter having a high-voltage side circuit arrangement (2) which is designed to convert a high-voltage side DC voltage (21) into an average DC voltage (31), and which has a first potential-separating DC-DC converter (5) which supplies the high-voltage DC voltage ( 21) receives and converts into the mean DC voltage (31); with a high-voltage side control device (22), which is adapted to operate the first potential-separating DC-DC converter (5) with a substantially fixed transmission ratio; with a first and a second low-voltage side circuit arrangement (4) which are designed to convert the average DC voltage (31) into a constant first and a constant second low-voltage side DC voltage (41, 51) and which comprise a number N2 of parallel first step-down converters (6) and having a number N3 of second step-down converters (8) connected in parallel receiving and reducing the average DC voltage (31) to the first and second low-voltage DC voltages (41, 51); and with a low-voltage side control device (42) which is designed to detect the average DC voltage (31) and to regulate the first and / or second buck converters (6, 8) so that the first and / or second low-voltage DC voltage (41 , 51) is kept at a constant value.