Signal flow graph modeling of a cascaded coupled inductor-based high step-up DC-DC converter

In this paper, the small signal flow graph method and Mason gain formula are applied for a cascaded coupled inductor (CL) based high step-up DC-DC converter is presented in order to obtain the average model of the converter. The influence of duty cycle and input voltage to frequency characteristics is investigated. Besides, in order to validate proposed signal flow graph modeling, small signal and large signal responses are compared. Various transfer functions are derived and have been validated through frequency and dynamic responses. The results show that presented signal flow graph model is significantly compatible to the converter.