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This work introduces a generalized version of the pulse width modulation (PWM) switch model applied in the small-signal modeling of converters based on the multistate switching cell (MSSC) operating in discontinuous conduction mode (DCM). It consists of extending the concept formerly introduced by Vorperian for the representation of multiphase converters in DCM, yielding a circuit-based approach that does not rely on matrix manipulations unlike state-space averaging (SSA). The derived dc and ac models are valid for any number of switching states and any operating region defined in terms of the duty cycle, thus allowing for determining the voltage gain and distinct transfer functions. A thorough discussion of results is presented to demonstrate the applicability of the derived models to represent distinct configurations of the MSSC. [ABSTRACT FROM AUTHOR]

The integration of switched-capacitor voltage multiplier cells in basic converter topologies has been studied to provide voltage gain and voltage stress reduction. However, SC cells do not provide current sharing and additionally they induce high current spikes in the devices, which are limitations of these structures to operate in high power levels. The main contribution of this paper is to overcome this drawback proposing the use of a multistate switching-cell for current sharing in SC-based boost converters, which reduces the current stress in the power devices and increases the power levels of this family of converters. The proposed concept can be generalized for m number of SC cells and n number of switching cells to increase the voltage gain and current levels. Furthermore, it can be applied to other basic structures. The theoretical analysis of the proposed structure was evaluated experimentally in a 3 kW boost-type dc-dc converter, achieving 200 V to 1200 V voltage gain, and reaching 98.4% of maximum efficiency.