Alleviate the Voltage gain of High Step-up DC to DC converter using Quasi Active Switched Inductor Structure for Renewable Energy

The demand for non-isolated high step-up DC-DC-dc converters in applications such as DC backup energy systems for UPS and photovoltaic has been gradually increasing. Generally, Boost converter should operate at high duty cycle in order to get the high-output voltage but it generates more EMI, conduction loss and increase the switch rating. High voltage gain DC-DC converter implemented quasi-active switched-inductor structure for a non conventional system is included in this paper. The PV system is available in the proposed system as well as two coupled inductors with magnetic core, two capacitors, two active switches, three diodes and PI filter [1]. The input supply is connected in shunt with primary part of the coupled inductor for charging. Meanwhile the charged coupled inductor is discharged in series manner along with the source and the capacitor in order to get efficient high output voltage with proper duty cycle is selected. The diode capacitor set will act as a clamp circuit so that the voltage conversion ratio by the coupled inductor structure is further improved to high level with less stress on the switch. In order to reduce the conduction loss by the switches used we preferred MOSFET switches with very low on state resistance. The reverse recovery problem is overcome with the help of active clamp circuit [2]-[3]. The proposed circuit model is simulated using MATLAB.