Global Hybrid Modeling and Control of DC-DC Converters:A Boost Converter Topology

Developing efficient and appropriate modeling and control techniques for DC-DC converters is of major importance in power electronics area and has attracted much attention from automatic control theory. Since DC-DC converters have a complex hybrid nature, recently several techniques based on hybrid modeling and control are introduced. These techniques have shown better results as compared to conventional averaging based schemes with limited modeling and control abilities. But current works in this field have not considered all possible dynamics of the converters in both Continuous and Discontinuous Current Modes (CCM, DCM) of operations. These dynamics are results of controlled and uncontrolled switching phenomena in DC-DC converters. Using Mixed Logical Dynamical (MLD) systems a new exact and non-averaged model is presented to control a DC-DC boost converter by considering all possible dynamics in both CCM and DCM operations. Using hybrid predictive control, based on Mixed Integer Quadratic Programming (MIQP), physical constraints such as maximum inductor current and capacitor voltage are also considered during the controller design. The transient and steady state performance of the closed-loop control over a wide range of operating points from open circuit to short circuit shows satisfactory operation of the proposed modeling and control approach.

Keywords:

Hybrid Systems , Mixed Logical Dynamical systems (MLD) , Model Predictive Control (MPC) , Mixed Integer Quadratic Programming (MIQP) , DC-DC boost converter