A low complexity control system for a hybrid battery-ultracapacitor power source

A low complexity control system for a conventional hybrid battery-ultracapacitor power source with two individual DC/DC converters is proposed in this paper. The advantages of the proposed control system are that it (i) allows to allocate the high frequency current demands to the ultracapacitor, (ii) allows to specify the current limits for both the battery and the ultracapacitor, (iii) maintains operation of the battery within its state of charge limits, (iv) maintains the ultracapacitor voltage at a predefined value and (v) charges the ultracapacitor from the battery rather than from the common DC bus. Presented simulation results verify operation of the proposed system.