A new 42 V automotive supply system based on conventional 14 V alternator

This paper is aimed at the study of conventional 14 V automotive electrical supply systems as a basis for the development of a novel 42 V supply system capable to provide maximum power to both the vehicle´s battery and the on-board consumers. By analyzing the operating characteristics of the 14 V Lundell alternator system with conventional three-phase full-bridge diode rectifier, the conditions for maximum output power at various alternator driving speeds are determined. Whereas in a conventional alternator-rectifier system the maximum power output on a wide operating speed range is obtained at working voltages below 42 V, the paper proposes the modification of the conventional system by introducing a boost converter. The operating characteristics of the new system are analyzed by performing simulations using the MATLAB SIMULINK programming environment.