Analysis of the safety operation limits of a Single-Phase Active Multi-Level Rectifier with voltage sag ride-through capability

Usually, active rectifiers are used as power factor compensators besides to its natural ability to maintain load regulation in the DC bus. Since the AC mains can be affected by voltage sags, is convenient to extend the Single- Phase Active Multi-Level Rectifier functions to have ride- through voltage sag capability. It is important to know the safety operation limits under all possible circumstances in order to obtain a wide operation range considering the good performance of the system. In this paper, an analysis of the operation limits considering duty cycle, modulation index, over currents and power losses as function of the voltage sag magnitude is presented and validated with simulations and experimental results for a 1 kVA prototype.