A DSP-Based Control Strategy For Single Phase Power Factor Corrector

The rectifier scheme that direct current supplying with power electronic equipment is obtained by alternating current being rectified is widely applied in power electronics field. However, the rectifying circuits result in input current distortion, input power factor greatly decrease. With promulgation and obliging actualization of IEC 1000-3-2 etc. international standards, Power Factor Correction (PFC) technique become a hotspot of research in power electronics field.Based on average current mode, the paper introduce the design and implementation of a fully digital controlled single-phase boost power factor corrector with fast response . The control-loop circuit is realized using digital control and the corrector can tend to unity power factor, lower current harmonics and high transfer efficiency.The double closed-loops framework is applied in the PFC control circuit and the PI algorithm is adopted as system' s control algorithm. The paper research small-signal model of PFC circuit and build thesimplified average-small-signal model of the system. The thesis develop design method of PI regulators which are applied in double closed-loops system. Furthermore, the sampling algorithm of votage and current variables is also analysed in this paper.The prototype include three parts. The main circuit adopt Boost converter topology; the control circuit is made up of ADSP-21065L core processor, A/D converter and CPLD which realize the functions of Digital Pulse Width Modulation(DPWM) and address decoding; the auxiliary power supply afford work voltage of every device.The software system consist of some software modules which realizing independent functions, such as initialization module, PI algorithm module, sampling algorithm module and interrupt module. Under connection of the main program, these modules realize an integrated system.All design thoughts and theoretical results are verfied by experiments on prototype.