Integration of supercapacitors as transient energy buffer in automotive power nets

Abstract

Load fluctuations in an automotive power net can cause significant perturbations of the supply voltage. A quality improvement for the electrical power supply can be achieved by connecting supercapacitors in parallel to the battery as a transient energy buffer. Effective voltage stabilisation and steadier generator output current were observed in an experimental investigation of such a power net modification. In addition to the increase of the peak power capability of the power net, charge throughput and rms-current in the battery were reduced. A concept and operation strategy aiming automotive requirements for the integration of supercapacitors into the power net are proposed. The resulting system was named "dynamic power assistance".