Piecewise affine modeling and control of a step-up DC-DC converter

The paper considers optimal control of a synchronous step-up DC-DC converter. The hybrid dynamics are approximated by a piecewise affine (PWA) model and an MPC problem is formulated where performance is optimized subject to constraints on state and control input. The solution is represented by a look-up table which can be efficiently implemented in applications where the switching frequency is high. An important aspect of the PWA model introduced in this paper is the fact that it is continuous in both state and input. The proposed PWA modeling approach is compared to a previously published method for PWA approximation of a boost converter where continuity is not guaranteed. The comparison shows that imposing continuity is essential to obtain good performance and low complexity solutions.