Multiloop Controller for N-Stage Cascade Boost Converter

Abstract

In recent years, the development of new technologies is requiring wider conversion ratios. A possible solution to this problem is to use n-stages connected in cascade; however, the major drawbacks are: (a) the total losses are increased mainly by the active switches, and (b) a more complex control circuitry is required. An alternative solution is to use a cascade boost converter with a single active switch. In this paper, nonlinear and linear models are given for the above converter. A controller is developed using average current-mode control where the current of the first inductor is selected for feedback purposes. For the inner loop, a current gain and a high gain compensator are selected. For the output loop, a conventional PI-controller is designed.