| The power network is polluted by harmonic current from the traditional AC/DC converter. AC/DC converter is most widely used in electronic devices. In order to reduce the harmonic pollution of power supply and improve the power factor, more power factor correction technology is used. At present, the single-phase power factor correction(PFC)is already developed, but the three-phase active power factor correction (APFC)is still in the stage of developing.This thesis presents a new control model of three-phase APFC circuit, which based on the model of One-Cycle-Control and has an advantage of low cost and high performance. Further more, this thesis presents a novel dual-transistor three-phase power factor correction circuit. Single-Switch boost type Harmonic Injection APFC circuit and Dual-Switch boost type One-Cycle-Control. APFC circuit have the merits of high control precision, simple circuit structure.The merits of digital control include simple hardware, flexible control and easy to realize advanced arithmetic etc. In the current it is popular to use digital control in APFC circuit. One-Cycle-Control algorithms and multiple-loop Control algorithms can be implemented in APFC circuit by digital signal processors (DSP).At first, this thesis introduces the classification and the virtues and defects of correction technology for active power factor correction. After introducing the operating principle of One-Cycle-Controlled three-phase single-switch Boost rectifier, the reason why the proposed circuit can reduce the input line current total-harmonic-distortion(THD), improving the power-factor and characteristics of the whole system is also given. The advanced dual-switch circuit is proved and introduced the influence of the duty cycle control. Then, Saber is the popular simulation software and used to simulate the propose circuit. Based on the simulation waveforms, an experimental installation is given. Finally, the experimental waveforms and results are given.
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