Extension of minimum separable switching configuration modelling to single-stage AC/DC converters with direct power transfer

This study extends the usage of minimum separable switching configuration (MISSCO) in generating circuit-oriented average model to more complex converter structures, which contain more than one switching cell, for example, single-stage AC/DC converters, in systematic and efficient manner. The model is capable of both large and AC small signal analyses with high accuracy. Also, the model gives electrical information of input and output ports as well as the intermediate bus voltage. Unlike the state-space averaging technique, the model is fully compatible with general-purpose circuit simulators such as SPICE. This greatly facilitates the analysis and design of the converters. In this study, a generalised MISSCO model for non-isolated AC/DC converters is presented and applied to a recently reported AC/DC converter as an example. Bode plots of transfer functions are also given for designing the feedback controller. Both its steady-state and frequency performances will be verified by simulation, experimental results and compared with state-space averaging counterpart.