Investigation On Single Stage Power Factor Correction Techniques

With only one set of control system, single-stage PFC converter can realize the input current shaping and the fast regulation of output voltage. It especially fits low-power occasion well because of the advantage of simple structure and low cost. However, the energy-storage capacitor voltage is uncontrollable, varying with the input voltage and load. So how to reduce the voltage of energy-storage capacitor is the main problem of single-stage PFC converter.At first, the present research of active Power Factor Correction technology is introduced. And then various topologies of single-stage PFC converter are compared. The universal model of Boost single-stage PFC converter is concluded in the end.Based on the above work, a new topology of single-stage PFC converter is presented in this paper. The operation principle of the circuit is analyzed in detail. Starting with the steady-state analysis, this paper presents the large-signal model of the circuit, designs the main parameters of the circuit, deduces the relation between inductance and energy-storage capacitor voltage, and presents the simulation and experimentation waveform of the circuit. The theoretical analysis and experiment indicate that the energy-storage capacitor voltage can be effectively reduced in this converter.On the basis of the new single-stage PFC converter, the paper adds an additional transformer winding, forming the bus voltage feedback to further reduce the voltage across the energy-storage capacitor but to reduce the power factor. The turns of the transformer additional winding should be determined from the trade-off between lower voltage across the energy-storage capacitor and lower total harmonic distortion of input current. The paper presents the theoretical analysis of input current distortion, deducing the relation between inductance and energy-storage capacitor voltage and designing the main circuit and close loop parameters. Simulation and experimental results prove the validity of design.Finally, t he p aper c oncludes t he r esearch findings, and p oints o ut s ome future research areas.