Analysis and extension of switched inductor and capacitor based high gain DC-DC boost converter with flexible control at higher gains

Abstract

Microgrids get the majority of their power from renewable sources such as PV (photovoltaic) and FC (fuel cell). To achieve the desired bus voltage in a DC microgrid, a conventional DC-DC converter used as an interconnecting device must operate at a high duty ratio, which may be detrimental to the device’s health and lead to issues including diode reverse recovery problems, unwanted transient response, voltage ripples, losses, and decreased efficiency. Typically, converters with a high gain are suggested to deal with such critical issues. This article analyses basic and its extended double leg active switched inductor-capacitor (A-SLC) based dc-dc converters. Simulation and hardware testing are then used to validate their performances. Not only this new converter has a higher voltage gain, but also it has a wider duty range since it operates with two-duty ratios. Moreover, it has the lowest voltage stress across the switches and a continuous current at the input, making it a viable option for renewable energy systems. In addition, the property of the expanded active SLC converter to run with double duty ratios facilitates simultaneous control of the MPPT and the voltage output.