Analysis, modelling, and simulation of droop control with virtual impedance loop applied to parallel UPS systems

This paper explores a control strategy for parallel uninterruptible power systems (UPS). The control technique used in that work was based on the droop control method. This method is usually applied to achieve good active and reactive power sharing when communication between the inverters is difficult due to its physical location. This paper has considered that the UPS systems there were no communication between their controls. A detailed mathematical model about the explored system is shown in that work and simulation results are presented in order to prove the theory presented.