Research On Key Techniques Of Single Phase Single Stage Full Bridge PFC Converter

In order to eliminate harmonic pollution and improve power factor, PFC(Power Factor Correction, PFC) began to be concerned and used. Among them, single-stage APFC become the focus of the current study because of its simple structure, low cost, high efficiency and other advantages, this paper conducted a study in control technology and application problems of single-stage full-bridge PFC converter.There is a large voltage spike on the bus during the circuit commutation process, because of the existing of leakage inductance in transformer, it will increase the voltage stress of the switch. In this paper, the problem of voltage spike can be solved with active clamp auxiliary link based on active clamp. The energy stored in the clamping capacitor will be transferred to the load by DC/DC conversion. The results show that this method has a good performance on voltage spike suppression by using PSIM simulation.Single-stage PFC converter realize PFC and DC/DC conversion in one stage circuit, so there is large voltage ripple in the output side whose frequency is double of line frequency, so the output characteristic of the system is influenced. In this paper, based on active clamp auxiliary link single-stage full-bridge PFC converter while extracting the voltage ripple, using the ripple control the auxiliary link output current to reduce the output voltage ripple. The performance of this method has be proved to be able to reduce the output voltage ripple without affecting the system power factor correction by using Simulink simulation and hardware circuit experiment.The main circuit of inverter use prediction control algorithm, which has advantages with small amount of computation and simple structure. Prediction algorithms and the effects of the voltage loop were studied in detail in this paper, and using the original prediction algorithm, a fast dynamic response capability improved predictive control algorithm is proposed, which can achieve rapid dynamic and PFC. Results show that the algorithm has good control performance by Simulink simulation. Finally, the experiment results show that the proposed method can be able to reduce the output voltage ripple and voltage spike without affecting the system PFC and fast dynamic response capability.