Title: Fuel cells/super-capacitor and battery/super-capacitor power control system assessment and lifetime cost for an UPS
Authors: Imen Ben Amira; Abdessattar Guermazi
Addresses: Electrical Department, Sfax Engineering National School, University of Sfax, P.O. Box 1173, 3038 Sfax, Tunisia ' Electrical Department, Sfax Engineering National School, University of Sfax, P.O. Box 1173, 3038 Sfax, Tunisia
Abstract: Most common uninterruptible power supplies (UPS) use batteries, super-capacitors (SCs) and fuel cells (FC); either alone or combined together. Two 500 KVA UPS systems relying on FC/SCs and on lithium ion (Li-ion) batteries/SCs have been studied in this paper. Indeed, a power management system has been established to control each storage system power. Then the effect of the hybridisation has been deduced. The aging Li-ion batteries parameters have been considered by representing their effects on the charge/discharge curve and on the internal temperature such as the working temperature, the depth of discharge (DOD) and the charge and discharge currents. Moreover, possible FC degradations have been discussed. The start/stop cycling, the power variations and the high power loads degradations have been taken into consideration in order to estimate the FC lifetime span using a prediction formula. Furthermore, the UPS costs have been studied in order to estimate the best average cost.
Keywords: fuel cell; super-capacitor; SC; battery; lifetime; cost; degradation; uninterruptible power supply; power control.
International Journal of Digital Signals and Smart Systems, 2018 Vol.2 No.3, pp.257 - 276
Received: 28 Feb 2018
Accepted: 22 Sep 2018
Published online: 09 Jan 2019 *