Single-stage single-switch power factor correction (PFC) rectifiers for high output voltage applications are investigated. Considerations for selecting a power stage for high-gain PFC are suggested and discussed. Accordingly, several candidate topologies for high-step-up DC/DC converters are identified and overviewed. A modified PFC OCC control scheme with extended capabilities is suggested to control the proposed high step-up PFC rectifiers. The proposed controller provides a simple and low-cost solution that can accommodate a wide range of rectifiers. Theoretical analysis is supported by simulation and experiments.