A Family of Single-Stage High-Gain Dual-Buck Split-Source Inverters

In this paper, a family of single-phase single-stage high-gain dual-buck split-source inverters (SSIs) is proposed. The proposed inverters have the combine benefits of SSI, dual-buck inverter (DBI), and high-gain dc-dc converters. Similar to the DBI, they provide high reliability by eliminating shoot-through issues, increase switching frequency and efficiency by using power MOSFETs without leading the body diodes to reverse recovery issues, and decrease pulsewidth modulation (PWM) dead-time. In addition, voltage boost operation is achieved in a single stage without using any additional active switch, which is in favor of lower control complexity and lower cost. On the other hand similar to the SSI, buck-boost dc-ac power conversion is realized in a single stage. However, compared to the SSI, the proposed inverters have no shoot-through issues, MOSFETs can be used without reverse recovery issues, dead-time can be minimized, switching frequencies can be increased, and external fast recovery diodes can be used to improve efficiency. In addition, four different high-gain dual-buck SSIs are presented. As an example, the proposed switched-coupled-inductor split-source DBI is analyzed and compared with the other proposed structures. To validate the theoretical analysis, a 300-W experimental prototype is designed and tested at 25-35-V input voltage, 155 V-peak output voltages and 50 kHz.