Design and Analysis of Two-switch Semi-quadratic Z-source Type Boost Converter

A semi-quadratic Z-source type boost converter (SQZBC) exhibiting improved voltage gain is proposed in this paper. It is a two-switch based boost converter and operates with less duty ratio range (i.e. 0 to 0.5). It is able to establish highvoltage transformation ratio like the conventional quadratic boost converter but at a lower duty ratios. To achieve this, three chargepump capacitors along with two inductances are utilized in the converter formulation. An additional capacitor is used across the load to ensure constant voltage along with suppression of ripples. Principle of operation is explained for the continuous inductor current mode of operation. Steady-state analysis is performed and the converter elements design equations are formulated. Later on state-space models are formulated to quantify the proposed converter dynamic behavior and then to design suitable controller. A 36V to 100/200 V, SO W prototype SQZBC is constructed for experimental verification. Measurement results are supported with simulation results to demonstrate the proposed high gain boost converter salient features.