Fuzzy Control of Power Factor Preregulators

In this paper, a fuzzy logic-based controller for power factor preregulators (PFPs) is investigated. Through this approach it is possible to obtain low-distorted and in-phase line current without the need for sophisticated mathematical analysis or complex models to design the controller. Moreover, the intrinsic nonlinearity of this control technique allows improved dynamic response and increased robustness as compared to linear approaches. In the paper, controller design and operation are discussed, and implementation by a microcontroller is described. Actual power converter operation is analyzed by simulation in the case of a boost PFP, demonstrating the feasibility of the approach.