Power factor correction (PFC) converters are of three types, namely, boost- type, buck-boost-type, and buck-type.Out of these, boost-type is the standard type of PFC converter, which is used in a wide range of applications. Buck-boost-type converters, in contrast, are used for more specific applications. Although the buck-type converters have been rarely used previously, they have been used for applications such as LED drivers in recent years. Moreover, buck-type converters have some advantages: they are suitable for low output voltages, and are lighter and compact compared to buck-boost-type converters.Therefore, they should be used for a wider range of applications. In this paper, we propose a buck-type PFC converter using a novel control strategy, which realizes outstanding results for simple circuits. Furthermore, the operating principles of the control circuit and an evaluation of the results for a 100-W prototype are described in detail.
