An Isolated High Step-Up Three Switch Quasi-Z-Source DC-DC Converter.

In order to solve the problem of insufficient boost capability and system stability of traditional boost converter, an isolated quasi-Z-source (qZS) high step-up dc-dc converter with three switches is proposed in this paper. In comparison with conventional qZS converter, reduced one active switch, the proposed converter has significant step-up voltage conversion ratio, lower voltage stress across the active switching devices and continuous input current with low current ripple. The operation principle, the design of the parameters, the performance compared with other step-up converters are presented. Finally, the simulation model is built by Matlab/Simulink to verify the correctness of the theoretical analysis.