An Control Strategy for Switching Converters in Sliding-Mode Current Control

The design of a two-loop control for nonminimum phase-switching converters is presented in this letter. An internal sliding-mode control loop forces the converter inductor current to follow the reference established by control of the output voltage in an outer loop. Simulations of both time and frequency responses of the output voltage show a faster and more robust behavior than in the case of a conventional approach using a PI controller in the external loop. Experimental results are in good agreement with the simulation predictions.