Switched-Capacitor High Voltage Gain Z-Source Converter With Common Ground and Reduced Passive Component

Abstract

Conventional dc-dc Boost converter has limited boost capacity, and its power device suffers high voltage stress. A novel Z-source based dc-dc boost converter featured with high step-up capability and low device voltage stress is proposed in this paper. The proposed topology can also provide a common ground for input and output, which is lacking in the traditional Z-source topology. Compared with other high step-up topologies, the proposed converter can achieve higher voltage gain under the same duty ratio and maintain low voltage stresses on the switch and diode. Moreover, there are fewer passive components in the proposed structure than in other structures. The steady-state analysis for the continuous conduction mode and discontinuous conduction mode is also provided in this manuscript. Finally, a prototype circuit with 40V-60V input voltage, 400V output voltage and 200W output power is implemented in the laboratory. Experiment results confirm the analysis and the features of the proposed converter.

Keywords

• DC-DC converter
• impedance network
• high step-up
• switched-capacitor