Three Topologies of a Non-Isolated High Gain Switched-Inductor Switched-Capacitor Step-Up Cuk Converter for Renewable Energy Applications

This paper introduces three topologies of a non-isolated high gain step-up Cuk converter based on a switched-inductor (SL) and switched-capacitor (SC) techniques for renewable energy applications, such as photovoltaic and fuel cells. These kinds of Cuk converters provide a negative-to-positive step-up dc–dc voltage conversion. The proposed three topologies SLSC Cuk converters increase the voltage boost ability significantly using the switched-inductor and switched-capacitor techniques compared with the classical Cuk and boost converters. The proposed Cuk converters are derived from the classical Cuk converter by replacing the single inductor at the input and output sides with a SL and the transferring energy capacitor by a SC. The main advantages of the proposed SLSC Cuk converters are achieving a high voltage conversion ratio and reducing the voltage stress across the main switch. Therefore, a switch with low voltage rating and thus, of low RDS-ON can be used, and that leads to a higher efficiency. For example, the third topology have the ability to boost the input voltage up to 13 times when D = 0.75, D is the duty cycle. The voltage gain and the voltage stress across the main switch in the three topologies have been compared with the classical Cuk and boost converter. The proposed three topologies avoid using a transformer, coupled inductors, or extreme duty cycles leading to less volume, loss, and cost. The proposed SLSC Cuk converters are analyzed in continuous conduction mode (CCM), and they have been designed for 12 V input supply voltage, 100 W rated power, 50 kHz switching frequency, and 75% duty cycle. A detailed theoretical analysis of the CCM is represented and all the equations have been derived and matched with the results. The proposed three topologies SLSC Cuk converters have been simulated in MATLAB/SIMULINK and results are discussed.