Switching Flow Graph Modelling of RRPP Based DC-DC Converter

Objective: Small-signal modelling is a widespread analysis practice in power electronic converters which is used to fairly accurate the performance of non-linear devices with linear equations. The order of the dc-dc depends on the non-linear elements of the system. As the number of non-linear element of the converter is high, it’s modelling and control becomes extremely complicated. Thus, there is a need for generalization of such converters by small signal modelling. Traditional modelling schemes using the averaging and small-signal linearization procedures are utilised for the advance modelling of the converters. Method: In this work, the purpose of the switching flow graph (SFG) and the Mason’s gain formula aid the solution of the equations. The duty cycle to output and the input to output transfer functions are obtained. Those transfer function can be used for closed loop examination. Findings: Open loop analysis of the converter is done and the outcomes are verified through simulation. Theoretical and simulation results are shown to prove the accuracy of the developed small signal models. The derived topology is unstable in open loop condition. A prototype is developed to validate the performance of the proposed topology. Improvement: Closed loop analysis can be carried out with any type of controller.