This paper presents a performance evaluation of a proportional-integral (PI) with proportional-derivative (PD) feedforward control for the output voltage of a single-phase off-line uninterruptible power supply (UPS) without using additional sensors. The control system is explained and simulation results are presented to analyze the steady state and transient response of the implemented voltage control. A laboratorial prototype was developed, and acquired experimental results considering linear and nonlinear loads are presented and discussed, corroborating the obtained simulation results.