Analysis and carrier-based modulation of Z-source NPC inverters

作者：Dehghan Seyed Mohammad^*; Mohamadian Mustafa; Gharekhani Reza

来源：International Journal of Electronics, 2012, 99(8): 1075-1099.

DOI：10.1080/00207217.2011.653948

• z-source inverter
• multilevel inverters
• carrier-based PWM modulation
• neutral-point-clamped (NPC) inverter
• power conversion

Multi-level neutral-point-clamped (NPC) inverters are widely used in high and medium voltage applications. However, these inverters are only buck-type converters. Recently z-source NPC inverters have been proposed as the buck-boost three-level inverter. New inverters use a z-source network as the input stage. This article analyses the features and limitations of two main topologies of z-source NPC inverters (dual z-source network NPC inverter and single z-source network NPC inverter). The low-frequency ripple of the inductor current and the capacitor voltage of the z-source networks in the z-source NPC inverters are surveyed. This article also proposes two novel PWM methods for the z-source NPC inverters, which can be easily implemented experimentally. In the proposed methods, generated switching signals for the conventional NPC inverter are modified for the z-source NPC inverter using a simple logic circuit considering the boost factors and the power sharing ratio. The performance of the proposed simple PWM methods is verified by simulation and experimental results.

• 出版日期2012