A Study on Effect of Dynamic Quantized Resolution on MPC Based DC-DC Converter with Combinatorial Optimization

In recent years, there is a demand for energy conservation as energy problems have become more serious and renewable energy attracts attention. This paper focuses on model predictive control (MPC) for DC-DC converters that contribute to the realization of accurate operation for renewable energy systems. Digital control dc-dc converter performs its control calculation within one control cycle, however, MPC may not complete the calculation since it includes an optimization problem. To avoid such a computation burden, we propose an enumeration based MPC method using dynamic quantized resolution for PWM dc-dc converters. In the step-down dc-dc converter using the proposed method, the resolution of the control input is dynamically changed to maintain stable steady-state control, and coarse resolution control to improve the response in the transient state. The proposed method is evaluated by simulation and it is revealed that our method maintains superior characteristics with a fixed amount of calculation.