Research On Digital Control Technology For APFC

Nowadays APFC (Active Power Factor Correction) plays an important role in power electronics field. It is used in many applications. During the last decade,there has being a large interest in APFC. But the traditional analog-control APFC has some shortcoming, the digital-control APFC becomes a research hotspot with the development of digital-control technique.This thesis sums up the main characters of APFC technology, analyzes the means and basal theory of all kinds of APFC technologies and illustrates the necessary and importance of the digital APFC. Studies the work principle and key technology of the Boost PFC circuit, designs a digital Boost PFC converter, this converter works in average current control means based on Si8250, adopts current and voltage double closed loop control and PID control algorithm.The control of APFC is digital control. The software system consist of a main program and a interrupt subprogram, which contained some modules to realize independent functions, such as initialization module, soft-start module and sampling algorithm module, etc. Under connection of the main program, these modules realize an integrated system, which is brief. The digital-control technique brings the advantages of simple circuit, immunity to noise, high reliability and debug expediently. So it is easy to update system with immovable circuit to satisfy the need of variational clients.All design thoughts and theoretical results are verified by emulation and experiment.The orientation for this item was proposed at the end of this dissertation.