An improved DC-DC converter with high voltage gain based on fully tapped quadratic boost converter for grid connected solar PV micro-inverter

Abstract

The need to increase the voltage level produced by PV systems becomes an urgent task to be compatible with the requirements of the AC load, but we meet problems in the operation of the step-up converter at a high duty cycle which is not preferred due to the reduction in voltage gain, and also a higher number of turns ratio in the windings inductance coupled adds to the overall losses of the converter. This article proposes an improved DC-DC converter with a lower duty cycle by integrating three tapped-inductors in new topology, which combined quadratic boost converter and tapped-inductor boost converter. The proposed converter achieves a high voltage gain with a lower duty ratio (Gmax = 14.32) and a maximum efficiency of 98.68% is improved compared to the voltage gain and efficiency results of these converters in several recently published references. The analyses are done theoretically and supported with simulation results. A prototype of the proposed converter has been built to experimentally validate the obtained results.