Control Strategy for Optimal Combination of Supercapacitors and Battery in 500 kVA rated UPS

Accès à l'article complet (Open Access) : http://www.waset.org/journals/ijeee/v6/v6-16.pdfInternational audienceIn this paper we present an optimal method that combines supercapacitors with the battery in a 500 kVA rated uninterruptible power supply (UPS). Supercapacitors are used as high power storage devices to smooth the peak power applied to the battery during backup-time and to deliver full power during short grid outages. First, supercapacitors and battery models are developed then validated using Matlab/Simulink®. Second, the architecture and the simulation of the designed system combining the two types of storage devices are shown. Finally, extensive simulations are carried out to determine the gain in battery RMS current, the gain in energy losses, the energy efficiency of the global system and the elimination rate of peak power applied to the battery through the battery at a suitable rate, all impulse power demands would be satisfied by the supercapacitors. The influence of the SC's on the performance indicators is analyzed. Optimal combination of two storage devices is obtained taking into account the supercapacitors cost