A Novel Continuous-Time Equivalent Circuit for Boost DC-DC Converters

A novel continuous-time equivalent circuit suitable for boost DC-DC converters is presented in this paper. It has been developed on the basis of the averaging technique with the aim of achieving a good ripple-free representation of the state variables of the system, whatever the converter operating mode is, i.e. Continuous Conduction Mode (CCM) or Discontinuous Conduction Mode (DCM). This goal can be achieved on condition that an appropriate PWM pattern is introduced, which enables an almost perfect matching between state variables and their corresponding equivalent ones at the start of each sampling time interval. Apart from the inductor and the capacitor, the proposed circuit consists of some equivalent input voltage and output current sources, together with several constant and/or variable resistors, which depend on converter switching signals and circuital parameters. The proposed continuous-time equivalent circuit has been validated through a simulation study, which is performed by means of the software PLECS. Simulation results highlight the worth and the effectiveness of the proposed modelling approach, over both transient and steady state operations.