Implementation of Bridgeless Cuk Power Factor Corrector with Positive Output Voltage

A single-phase bridgeless Cuk ac/dc power factor correction (PFC) rectifier with positive output voltage is designed. For low output voltage product applications, the rectifier is designed to convert high input voltage to low output voltage. Due to no bridge diodes required and thus decreased input conduction losses, the rectifier efficiency can be improved. The proposed rectifier operates in discontinuous conduction mode, and the current-loop circuit is hence not needed. In addition, only a single switch is used in the rectifier to simplify the control circuit design. A simple translation method to have the positive output voltage in the Cuk converter is presented in the rectifier to reduce the component counts and the cost. The operational principles, steady-state analysis, and design procedure of the rectifier are analysed in detail.