An Internal Model Controller for Low Inductor Current Quadratic Boost Converter

DC-DC Boost converters have gained popularity as an interfacing power electronic converter in renewable based energy systems in recent times. Various topologies for DC-DC Boost converters are also proposed in literature for better efficiency and improved performances. A high value of boosting capacity is a desirable feature in those architectures. This proposed work presents a controller based on Internal Model Control (IMC) scheme and its tuning for one such Boost converter topology which has recently been proposed. This quadratic Boost converter (QBC)features low inductor current which results in improved efficiency. This paper includes mathematical modeling of the converter using State Space Averaging (SSA) technique to find a transfer function between control to output. This control Vs output transfer function of QBC is a non-minimum phase system of fourth order and presents a challenge to controller design because of its low damping ratio and high natural frequency. To solve this issue, an IMC based controller is designed and its performance with system is compared with that of the conventional PI controller to establish its superiority.