A Novel Time-Domain Based Design of PWM Controllers for Switch-Mode Converters and its Implementation by the C2000 DSP Family

A new time-domain design method for digital controller of PWM DC-DC converters that was developed, tested by simulations and verified experimentally. The proposed approach is based on the fact that the closed-loop response of a digitally controlled system is largely determined by the first few samples of the compensator. This concept is used to fit a digital PID template to the desired response. The proposed controller design method is carried out in the time domain and thus, bypasses errors related to continuous to discrete domain transformation and discretization. Digital PID controllers for a Buck and Boost type converters were implemented experimentally on a TMS320LF2407 DSP core. The code for the proposed PID control law was realized by assembly code to minimize the run time of the controller. Good agreement was found between the design goal, simulation and the experimentally determined response.