Average Current Mode Control of Series-Switching Post-Regulators Used in Power Factor Correctors

The application of the average current mode control (ACMC) to a new type of very efficient post-regulators is studied in this paper. This post-regulator, called series-switching post-regulator (SSR), has recently been proposed to improve the dynamic response series-switching of power factor correctors (PFC). The post-regulator exhibits very high efficiency due to the fact that only a part of the total power undergoes a power conversion process. Using ACMC, the bandwidth of the post-regulator increases in relation to the one obtained when a conventional voltage-mode control (with or without feedforward) is used. As a result, the attenuation of the input voltage ripple (100–120 Hz) increases and, a lower bulk capacitor can be used to obtain a low voltage ripple at the output, which is extremely important when a battery is connected at the output. This is rather common in distributed power supply systems.