Loss Analysis of Quasi Z-Source Inverter Using Superjunction-MOSFET

This paper proposes to improve quasi Z-source inverter (QZSI) performance by using Superjunction-MOSFET. 2 kW class laboratory prototypes were fabricated to confirm this proposal and to compare the performance with the conventional inverter system using Si-IGBT. From loss breakdown of the both methods in various boost ratios and load conditions, it was confirmed that the proposed method can be operated with lower total loss than the conventional method in lower boost ratio operations by its reduced inverter conduction loss. On the other hand, in higher boost ratio operation, the proposed method had higher conversion loss than the conventional method due to increased switching and inductor losses.