Auto-tuning of Digitally Controlled Boost Power Factor Correction Rectifiers Operating in Continuous Conduction Mode

This paper presents a robust auto-tuning technique for digitally controlled boost Power Factor Correction (PFC) rectifiers operating in continuous conduction mode (CCM). The proposed tuning approach perturbs the PFC current and voltage control loops through injection of digital perturbation signals, and achieves the desired crossover frequencies and phase margins for wide ranges of operating conditions and power-stage parameters through simple compensator gain adjustments. An added benefit of the proposed approach is a precise estimation of the filter inductance and capacitance values as a result of the tuning process, therefore providing useful information for any digital current-programmed control technique. Experimental results presented for a 300 W boost PFC rectifier demonstrate effectiveness, and robustness of the proposed technique.