An enhanced PWM method for loss balancing of five level T-type inverter in PV systems

摘要

Multilevel inverters have attracted much industry and research concerns in photovoltaic (PV) applications. Although, it is demonstrated that power switching devices are subjected to unequal distribution of power losses and the reliability of multilevel inverters becomes low in accordance. Therefore, a new pulse width modulation (PWM) method is proposed in this paper for loss balancing in single phase five level inverters. The proposed method swaps the utilization of power components through the line period using the redundancy property between the switching states of T-type multilevel inverters. In addition, natural balance of voltages over DC link capacitors is achieved using the proposed method. The superiority of the proposed method is verified using simulation and experimental prototypes.