An FPGA Prototype of Current and Voltage Predictive Controller for High Switching Frequency Buck Converter

A digital current and voltage predictive controller (CVP) is proposed for high switching frequency, low power SMPS. The predictions of the inductor current and capacitor output voltage are performed simultaneously by adopting a flexible PWM pattern that enables dynamic adjustment of the time of the voltage events. The CVP controller preserves the merits of predictive current-mode control and allows to further improve the dynamic performances. With the knowledge of the inductor current, the performances of the CVP controller are analyzed compared to a deadbeat controller. Experimental results of a current sensorless implementation verify better closed-loop performances than those of PID, RST and sliding-mode controllers. The lab-scale prototype implemented in an FPGA supports a switching frequency up to 4 MHz only limited by the discrete buck converter.