Research Of Active Power Factor Correction Based On Improved One Cycle Controller

With the rapid development of social economy, power quality has been widely concerned. If power factor correction technology were introduced in the electrical equipment it can significantly improve power factor of electrical equipment, reduce the input side current harmonics and improve grid power quality.This paper address the power factor correction research background and current situation, summarize several common topologies used in active power factor correction and analyze their advantages and disadvantages. It also details the Boost converter three current operating modes. This dissertation introduce several APFC control algorithms and analyze characteristics of each algorithm, and especially introduce one cycle control algorithm. One cycle control technology is a nonlinear switching control technology, with simple control method, fast dynamic response, high control accuracy and robustness characteristics, so that it has been used widely.This dissertation regard novel single phase voltage-doubler Boost APFC converter as research object, analyze operation principle of the circuit and then propose a voltage doubler Boost APFC converter based on OCC technology. In order to solve the problem of CCM OCC algorithm operate in DCM current model that an improved OCC algorithm is adopted which enable the converter operate from light load to full load and realize MCM control between DCM and CCM.From the Boost PFC operating state, the inductor current operation mode and the converter input admittance give a detailed derivation of improved OCC algorithm. A current correction factor technology is introduced to correct the difference between the sensed current and the average current under DCM state. Then build the simulation model to verify the feasibility of the improved OCC algorithm.Finally a voltage doubler Boost APFC prototype based on the platform of F28069 DSP is designed, which contain power circuit design, control circuit design and software design. By soft-start testing, load testing and load mutations testing demonstrate that the proposed improved OCC algorithm can achieve low THD and high power factor over wide load range.