An Effortless Space-Vector-Based Modulation for $N$ -level Flying Capacitor Multilevel Inverter With Capacitor Voltage Balancing Capability

摘要

Although inverters with high number of levels offer many merits, their utilization is hindered mainly by their complicated control. Overcoming this barrier gives them the opportunity to find more practical applications. This paper presents an effective closed-loop space-vector-based modulation algorithm to control flying capacitor multilevel inverters with linearly distributed flying capacitor voltages. This modulation technique drastically reduces the computational load. Besides, it is able to balance capacitor voltages more simply and effectively than other methods presented so far. It does not require any stored information from memory or a lookup table. Therefore, it permits online computation of the switching sequence. Moreover, due to the closed-loop structure of this method, the effect of system nonlinearity and capacitor voltage deregulation on performance of the modulation is reduced. Other advantages of the proposed algorithm are: low number of instructions, level-independent number of instructions, and simple extendibility to an arbitrary number of levels without considerable modification.