Rapid Control Prototyping Based Design of Buck Converter Using RTW/ MATLAB

Abstract

In this paper, rapid control prototyping (RCP) design of buck converter using Real-Time workshop (RTW/MATLAB) has been presented. The small signal model of buck converter is deduced using voltage mode control technique. Using frequency response method the gain and phase margins are obtained for open-loop frequency response, then proportional-integral-derivative controller with first order derivative filter (PIDF) is employed to design the feedback controller for closed-loop system of buck converter. Discrete simulation is carried out in MATLAB/SIMULINK software. The digital PIDF controller is then implemented through RCP design technique for buck converter. The advantage of RCP is that, it uses professional tools of Simulink model based on the ADC-PWM block sets and discrete PID controller block which can be converted into C-language program using RTW/MATLAB toolbox. Finally the overall program is then downloaded into the destination processor of DSP kit TMS320F2812 which is linked to the main circuit of buck converter composed of actual/experimental setup for closed loop implementation. The simulation and experimental results are compared, which indicate that the RTW-based feedback controller designed by RCP technique can effectively control the buck converter in the presence of input line voltage and output load current variations.