Control Strategy of a Quadratic Boost Converter With Voltage Multiplier Cell for High-Voltage Gain

Abstract

The need of dc–dc switching converters for power supplies with high-voltage gains has increased in the recent years due to new applications in areas as renewable energy systems, transportation, industrial, medical, and others. A quadratic boost converter is a useful topology to obtain a step-up output voltage; however, a major drawback is the presence of a higher voltage stress over the active and passive switches. In this paper, a quadratic boost converter is combined with a voltage multiplier cell and an output filter to offer a high-voltage gain converter with nonpulsating input and output currents. The expressions for the capacitor voltages and inductor currents are given, as well as the corresponding ripples that allow the proper design of the converter. The bilinear switched, nonlinear averaged and linear averaged models are derived such that the dynamical behavior of the converter is analyzed and used to design a control strategy. A step-by-step procedure is given to tune up a current-mode controller. Experimental results are shown from a prototype, which delivers an output voltage of 220 V and an output power of 300 W. Step load changes between 20% and full load are applied to exhibit the robustness of switching regulator.