An analog implementation to improve load transient response of PFC pre-regulators

作者：Cheung Martin K H^*; Chow Martin H L; Tse Chi K

来源：29th International Telecommunications Energy Conference, 2007-09-30 to 2007-10-05.

DOI：10.1109/INTLEC.2007.4448900

This paper presents an analog implementation to improve the load transient response of PFC pre-regulators. By means of a notch filter inserted between the output-voltage sensing network of the pre-regulator and the voltage control loop of the pre-regulator control circuitry, the bandwidth of the voltage control loop is greatly expanded without introducing extra input current harmonics into the pre-regulators. This approach uses operational amplifiers with R-C networks to realize the notch filter, therefore it can be implemented into the existing pre-regulators with minor modification. The notch filter can be applied in both continuous-conduction-mode (CCM) pre-regulators and discontinuous-conduction-mode (DCM) pre-regulators. Furthermore the size of the output capacitor of the pre-regulators can be reduced due to the expanded bandwidth of the voltage control loop. The improved load transient response of the analog notch filter is observed experimentally. A laboratory prototype of a 100W DCM flyback pre-regulator has been built to illustrate the benefits of this cost-effective solution.

• 出版日期2007
• 单位香港理工大学