Search results for "Uninterruptible power supply"
showing 2 items of 2 documents
Robust model-following control of parallel UPS single-phase inverters
2008
This paper presents a robust control technique applied to modular uninterruptible power-supply (UPS) inverters operating in parallel. When compared to conventional proportional-integral (PI) control, the proposed technique improves the response of the output voltage to load steps and to high distorted output currents, reducing the distortion of the output voltage. Furthermore, an excellent distribution of currents between modules is achieved, resulting in fine power equalization between the inverters on stream. The crossover frequency of the different loop gains involved is moderate, so that robustness to variations of the operation point and to modeling uncertainties is achieved. A compara…
UPS fuel cell based: An innovative back-up system
2007
The aim of the paper is to evaluate the technical feasibility and aspects related to the use, in an Uninterruptible Power Supply (UPS), of fuel cells instead of traditional electrochemical batteries. The proposed system, named UPS-FCB (Fuel Cell Based) presents a modular and versatile system configuration; particularly it is possible to integrate it with traditional UPS. Moreover the system features can be modified in terms of power, reliability, back-up time, etc., by changing the power devices. A detailed experimental analysis has been carried out on a passive stand-by UPS integrated with a FCB; experimental results can be easily extended to the other possible system architectures. © 2007…