Self-Balanced Operation of a Standalone PUC5 Multilevel Inverter Based on its Averaged Model

Compared to other multilevel inverter (MLI) topologies, the Packed U -Cells (PUC) inverter is capable of generating more levels with less components. Thus, this paper investigates the operation of a 5-level PUC (PUC5) inverter supplying an RL load in both open-loop and closed-loop operations based on its averaged dynamical model. The aim is to prove that the self-balancing, a natural feature of the converter, could be obtained by the selection of a regular phase-shift between two carrier signals when applying a Pulse Width Modulation (PWM) technique. Moreover, a nonlinear feedback scheme is proposed to ensure fast balancing of the capacitor voltage and good tracking of the output voltage reference. Simulations results are presented to show the performance of the proposed techniques in ensuring self-balancing of the capacitor voltage and high tracking quality of the desired values.