High Voltage Gain DC-DC Non-Isolated Converter with Generalized Stages

Abstract

In this paper, a non-isolated dc-dc converter is proposed to provide a high voltage gain with a low inductance requirement. The circuit can be generalized for multiple stages to realize the desired DC output voltage from a low DC voltage source. In the proposed topology, the capacitors and inductors are charged/magnetized in parallel and discharged/demagnetized in series during switched on and off period respectively to obtain a high step-up voltage gain. The proposed power circuit is suitable for many applications based on renewable energy and energy storage where the desired DC-link voltage requirement can be as high as 560V (three-phase inverter input), and input voltage can be as low as 48V (a string of four batteries or fuel cell). A detailed analysis of the steady-state operation of the power converter is provided in this paper to obtain the voltage gain of the converter. The circuit design is simulated in MATLAB Simulink to verify the results of the analysis of this converter. Further, the design guidelines are provided for the generalized form of the converter to achieve desired steady-state input-output gain.