Non Isolated DC-DC Step Up Converter with High Voltage Gain for Renewable Energy Applications

Abstract

In renewable energy applications high step-up dc-dc converters are widely used to maintain an uninterruptible power system. The necessity of a high step-up dc-dc converter is to rise the low voltage from photovoltaic (PV) or fuel cell based grid connected system to a relatively high bus voltage for the downstream dc-ac grid-connected inverter. The voltage gain of the conventional boost converter is restricted due to high ripple current and the low efficiency because of high duty cycle. This paper presents a non-isolated dc-dc step up converter with high voltage gain. The proposed converter can provide a large voltage gain at a small duty ratio. In addition, all the power switches work depending upon a single pulse width modulated (PWM) control signal, reducing the control complexity. At the beginning, the working principle and steady-state analysis in continuous conduction mode are explained in detail. Finally, simulation results justify the analysis of the proposed converter.