A Novel Control Technique for Digital Power Factor Correction

A novel control technique optimized for digital power factor correction (DPFC), which consists of two loops: "outer voltage loop" and "inner current loop", is presented. The current loop employs predictive dead beat (PDB) technique to boost the switching frequency. The voltage loop employs "voltage sensor-less technique", which senses in an interleaving manner the inductor current and derives information regarding the input and output voltages for use in output-voltage feedback and input-voltage feed-forward compensation. This control technique saves the DSP resources and alleviates itself from the limitation of the DSP processing speed. Also, it works for a wide range of input voltages with the addition of input-voltage feed-forward compensation. A boost controller is presented to demonstrate the applicability of this technique in a DPFC