DC-DC and AC-DC voltage doubler boost converter for UPS applications

Several topologies are adopted in uninterruptible power supplies (UPS), both having their advantages and disadvantages. They must be chosen in order to favor the characteristic of most interest. One of the main characteristics might be the voltage flexibility which can adapt different input and output voltages according to the characteristics of power grid and customer load, and the possibility of making galvanic isolation optional. In single-phase UPS, the voltage doubler boost circuit prevails due to its compactness. Thus, this paper presents the theoretical analysis and practical results of a modified voltage doubler boost converter applied as the front-end stage of single-phase uninterruptible power supplies aiming simplicity and robustness.