Internal model control of dc-dc boost converter exhibiting non-minimum phase behavior

Abstract

This paper investigates the application of two degree-of-freedom (2DOF) internal model controller (IMC) design approach for output voltage regulation of representative boost type dc-dc converter operated in continuous conduction mode (CCM). This system exhibits non-minimum phase behavior due to occurrence of a RHP zero, which poses limitation in the bandwidth available for any control scheme. The IMC structure provides an alternate parameterization of the conventional feedback controllers and is relatively easy to tune to achieve satisfactory servo and regulatory behavior simultaneously. To demonstrate the effectiveness of this 2DOF-EVIC control scheme, simulation studies have been conducted using SEVIULINK platform under different servo and regulatory scenarios. To begin with, simulations are carried out with plant dynamics simulated using linear transfer functions. To assess the feasibility of using the proposed EVIC controller on an experimental setup, the plant dynamics are later simulated using a nonlinear dynamic model. The simulation results clearly imply that the proposed EVIC performs better than the PID controller in linear as well as nonlinear simulations. Moreover, the performance of the IMC tuned using the linear simulation does not change significantly when used for operating the nonlinear plant.