Power supply for a pulsed load

摘要

A power supply ( 1 ) for a pulsed load ( 2 ) includes a first energy storage device in the form of a battery ( 3 ) which is in parallel with a second energy storage device in the form of a supercapacitor ( 4 ). Battery ( 3 ) and supercapacitor ( 4 ) are respectively modelled as: an ideal battery ( 7 ) in series with an internal resistance ( 8 ); and an ideal capacitor ( 9 ) in series with an equivalent series resistance (ESR) ( 10 ). Through use of a supercapacitor ( 4 ) having a low ESR with respect to the resistance ( 8 ), the power supply ( 1 ) facilitates continuity of supply to load ( 2 ). That is, during peak demand more of the load current will be supplied by supercapacitor ( 4 ) due to the lower ESR. Moreover, during times of lower load current demands the battery recharges the supercapacitor. This reduces the peak current needed to be provided by the battery and thereby improves battery longevity.