Design and Comparison of Digital Control Loops Analytical Models, Laboratory Measurements, and Simulation Results

A buck converter with a digital controller is modeled analytically and compared to laboratory measurements and simulation results. These models will help the practicing engineer in understanding the new digital controllers. This presentation provides engineers less familiar with digital control some tools and insight into how to characterize the behavior of these systems. The models are validated by comparing their results with experimental measurements. An analytical synthesis approach will be given to estimate the control loop PID values to design and assure the stability of these systems. This approach reduces design iteration and the resulting design can be further optimized in the laboratory and by way of the simulator. Additional simulation techniques and methods are presented which will help both young and more experienced engineers evaluate the robustness of these control systems. Finally, real life practical tips are provided to avoid common simulation and modeling traps.