Improved Digital Predictive Control of Switching DC-DC Converters

The time delay caused by sample and calculation is inevitable in digital control of switching dc-dc converters. This time delay will degrade the transient performance due to its effect on the bandwidth of the digital controlled switching dc-dc converters. It is thus very important to minimize this time delay effect to improve digital controller's performance. An improved predictive control is proposed and studied in this paper to minimize the time delay effect. The steady-state performance and the line variation and load variation transient response characteristic of buck converter by adopting this improved predictive control are studied by simulation and experiments. The characteristic comparison with analog control, conventional predictive control and improved predictive control are also performed. Experimental results give further verification of the analysis and simulation study results