Design of a High Step-up DC-DC Converter Based on QZSI with Low Voltage Dtress by Using Coupled Inductor Technique

High step-up structures are commonly used to upgrade the low voltage levels generated by renewable energy sources. In this paper, a high step-up structure based on Quasi Z-Source network is presented, which has a simple yet functional structure consisting of two inductors and two capacitors. Due to the duty cycle of about 50% for this converter, the problems of reverse recovery of diodes and stability are solved. In addition, the common ground of the power switch and the input source simplifies the control circuit. Using the coupled inductor technique as well as the voltage multiplier cell, the converter voltage gain increases significantly. In addition, the stacked capacitor is used to limit the voltage stress on the switch. The use of the proposed structure increases the voltage gain of the converter. The proposed structure also reduces the level of voltage stress on the semiconductors of the circuit, which reduces the cost and increases the efficiency of the circuit. The converter designed with 25V/ 400V input/ output 100Wouput power is simulated in PSpice software and the results are presented.